11th Annual Congress of the European Cardiac Arrhythmia Society Paris April 19-21, 2015 Scientific Program and Abstract Special issue

Special Program and Abstract issue of the 11th Annual Congress of the European Cardiac Arrhythmia Society (ECAS)

April 19–21, 2015

Paris, France

Hotel MeridienEtoile

Guest Editor: Prof. Samuel Lévy, MD Aix-Marseille Université, Marseille, France

ECAS Scientific Program

PROGRAM AT A GLANCE

11th Annual Congress of the European Cardiac Arrhythmia Society

SCIENTIFIC PROGRAM OF PRE-ARRANGED SESSIONS

ECAS 2015 ABSTRACT SESSIONS 1–4

Sunday, April 19, 2015, 10:30 AM–12:00 PM

Abstract Session 1: Atrial fibrillation ablation

Abstract Session 2: Sudden cardiac death. Prevention and management

Abstract Session 3: Atrial fibrillation and prevention of related thromboembolism

Abstract Session 4: Mechanisms of ventricular arrhythmias

ECAS 2015 ABSTRACT SESSIONS 5–8

Monday, April 20, 2015, 10:30 AM–12:00 PM

Abstract Session 5: Advances in atrial fibrillation ablation II

Abstract Session 6: Cardiac resynchronization therapy: techniques and outcome

Abstract Session 7: Mapping and ablation of ventricular arrhythmias

Abstract Session 8: Clinical and genetic aspects of ARVD/C

ECAS 2015 ABSTRACT SESSIONS 9–12

Tuesday, April 21, 2015, 08:30 AM–10:00 AM

Abstract Session 9: Atrial fibrillation mechanisms and management I

Abstract Session 10: Atrial arrhythmia mechanisms II

Abstract Session 11: Management of atrial arrhythmias

Abstract Session 12: Atrial fibrillation ablation III

ECAS 2015 POSTER SESSION A: PARTS 1 AND 2

Part 1: Supraventricular arrhythmias. Advances in mechanisms and management

Part 2: Atrial fibrillation characteristics and management

ECAS 2015 POSTER SESSION B: PARTS 1 AND 2

B Part 1: Arrhythmias and heart disease

Techniques and tools

B Part 2: Atrial fibrillation ablation

Screening athletes

ECAS 2015 POSTER SESSION C: PARTS 1 AND 2

Part 1: Cardiac resynchronization therapy

Arrhythmia mechanisms

Part 2: Sudden cardiac death and implantable cardioverter defribrillator

ECAS 2015 POSTER SESSION D: PARTS 1 AND 2

Part 1: Pacing and related complications

Atrial fibrillation and anticoagulant therapy

Part 2: Syncope

Ablation of ventricular arrhythmias

Invitation

Dear Colleagues,

This is an invitation to join us at the 11th Annual Scientific Congress of the European Cardiac Arrhythmia Society “ECAS 2015” to be held in Paris, France April 19 to 21, 2015, at the Meridien-Etoile Hotel (Porte Maillot). All those who attended previous editions of ECAS Congress know that it is a highly scientific and educational event in a cheerful atmosphere which facilitates interaction between the renowned faculty and the audience which is particularly appreciated by fellows. This edition promises to be successful and we will be delighted to have you among us in Paris next April.

Riccardo Cappato, MD

President of ECAS

Nicolas Lellouche, MD

Congress Chairman

Xavier Jouven, MD

Scientific Program chair

EXECUTIVE COMMITTEE OF THE EUROPEAN CARDIAC ARRHYTHMIA SOCIETY
President	Riccardo Cappato (Milan, IT)
Past President	Wyn Davies (London, GB)
Vice-President (Education and Research)	Richard Hauer (Utrecht, NL)
Vice-President (National Societies)	Massimo Santini (Rome, IT)
Vice-President (International Societies and EU)	Samuel Lévy (Marseille, FR)
Treasurer	Eli Ovsyshcher (Beersheba, IL)
Secretary General	Leo Van Wersch (Paris, FR)
Continuing Medical Education	Nicholas Peters (London, GB)
Relation with European Societies	Stefan Kaab (Munich, DE)
Chair Membership Program	Neil Sulke (Eastbourne, GB)
Organizing annual Congress	Gerhard Steinbeck (Munich, DE)
Education Committee	Thorsten Lewalter (Munich, DE)

Organizing Committee ECAS 2015

Riccardo Cappato, Wyn Davies, Xavier Jouven, Stefan Kääb, Gilles Lascault, Nicolas Lellouche, Samuel Levy, Michael Näbauer, Gerhardt Steinbeck, Reza Wakili

Gerhard Steinbeck MD

Program Committee

Samuel Levy MD

Nicolas Lellouche, MD

Andrey Ardashev; Alawi Alsheikh-Ali; Serge Barold; Leonardo Calo; David S Cannom; Riccardo Cappato; Sumeet Chugh; Wyn Davies; Roberto De Ponti; Heidi Estner; Jeronimo Farre; Mark Estes III; John Fisher; Robert Hatala; Richard Hauer; Ellen Hoffmann; Charles Jazra; Xavier Jouven (Chair); Stefan Kääb; Jean-François Leclercq; Gilles Lascault; Samuel Lévy; Thorsten Lewalter; Jean-Yves Le Heuzey; Shaowen Liu; Peter Loh; Pierpaolo Lupo; Chang Sheng Ma; Michaël Näbauer; Mohan Nair; Yuji Nakazato; Andrea Natale; Petr Neuzil; Promund Obel; Eli Ovsyshcher; Douglas L Packer; Luigi Padeletti; Nicholas S. Peters; Dubravko Petrac; Antonio Raviele; Amiran Revishvilli; Sanjeev Saksena; Richard Schilling; Gerhard Steinbeck; Massimo Santini; Neil Sulke; Dorwarth Uwe; Reza Wakili; Bruce Wilkoff.

Scientific Advisory Board
Masood Akhtar (Milwaukee, USA)	Bulent Gorenek (Eskisehir, TR)	Bertil S. Olsson (Lund, SE)
Etienne Aliot (Nancy, FR)	Stephen C. Hammill (Rochester, USA)	Oscar Oseroff (Buenos Aires, AR)
Maurits A. Allessie (Maastricht, NL)	Richard Hauer(Utrecht, NL)	Ali Oto (Ankara, TR)
Eckhard Alt (Munich, DE)	Habib Haouala (Tunis, TN)	Eli Ovsyshcher (Beersheba, IL)
Charles Antzelevitch (Utica, USA)	Yoshito Iesaka (Tokyo, JP)	Douglas L. Packer (Rochester, USA)
Andrey Ardashev (Moscow, RU)	Michiel Janse (Amsterdam, NL)	Luigi Padeletti (Florence, IT)
Serge S. Barold (Boca Raton, USA)	Charles Jazra (Beirut, LB)	Nicholas S Peters, (London, GB)
David Benditt (Minneapolis, USA)	Xavier Jouven (Paris, FR)	Dubravko Petrac (Zagreb, HR)
Poul Erik Bloch-Thomsen (Hellerup, DK)	Werner Jung (Villingen, DE)	Eric N. Prystowsky (Indianapolis, USA)
Jozsef Borbola (Budapest, HU)	Stefan Kääb (Munich, DE)	Antonio Raviele(Venice, IT)
Johannes Brachmann (Coburg, DE)	Prapa Kanagaratnam (London, GB)	Amiran Revishvili (Moskow, RU)
A John Camm (London, GB)	Joergen Kanters (Copenhagen, DK)	Dwight Reynolds (Oklahoma, USA)
Alessandro Capucci (Ancona, IT)	Bondo Kobulia (Tbilisi, GE)	Edward Rowland (London, GB)
Riccardo Cappato (Milan, IT)	Karl-Heinz Kuck (Hamburg, DE)	Sanjeev Saksena (New Brunswick, USA)
David S. Cannom (Los Angeles, USA)	Jean-François Leclercq (Paris, FR)	Massimo Santini (Rome, IT)
Sumeet Chugh (Los Angeles, USA)	Jean-Yves Le Heuzey (Paris, FR)	Maurizio Santomauro (Naples, IT)
Antonio Curnis (Brescia, IT)	Samuel Lévy (Marseille, FR)	Dipen Shah (Geneva, CH)
Philippe Coumel*	Berndt Luderitz (Bonn, DE)	Richard Schilling (London, GB)
D. Wyn Davies (London, GB)	Damian Gascon Lopez (Sevilla, ES)	Georg Schmidt (Munich, DE)
Hu Dayi (Beijing, CN)	Marek Malik (London, GB)	Jabir Sra (Milwaukee, USA)
Luc De Roy (Yvoir, BE)	Harry G. Mond (Melbourne, AU)	Gerhard Steinbeck (Munich, DE)
Sergio Dubner (Buenos Aires, AR)	Alessandro A Montenero (Rome, IT)	Neil Sulke (Eastbourne, GB)
Nils G. Edvardsson (Goteborg, SE)	Conception Moro Serrano (Madrid, ES)	Paul Touboul (Lyon, FR)
Michaël Eldar (Tel Aviv, IL)	Arthur J. Moss (Rochester, NY, USA)	Albert Waldo (Cleveland, USA)
Nabil El-Sherif (New York, USA)	Michael Nabauer (Munich, DE)	Hein JJ Wellens (Maastricht, NL)
Jeronimo Farre (Madrid, ES)	Gerald V. Nacarelli (Hershey, USA)	Bruce Wilkoff (Cleveland, USA)
John Fisher (New-York, USA)	Yuji Nakazato (Tokyo, JP)	David Wilber (Chicago, USA)
Guy Fontaine (Paris, FR)	Andrea Natale (Cleveland, USA)	George D. Wyse (Calgary, CA)
Robert Frank (Paris, FR)	Promound I. W.Obel (Johannesburg, ZA)
Seymour Furman (New York, USA)*	Brian Olshansky (Iowa City, USA)

*In memoriam

Abstract Selection

Each abstract has been sent to eight reviewers and been evaluated by a minimum of four of them..

The organizing committee would like to thank the abstract reviewers for their valuable help in the abstract selection for the ECAS 2015 program:

Etienne Aliot; Elad Anter; Serge Barold; Jean-Jacques Blanc; Poul-Erik Block Thomsen; Gerard Boink; Gunter Breithardt; Hugh Calkins; Leonardo Calo; John Camm; Riccardo Cappato; Mario Delmar; Roberto De Ponti; Luigi Di Biase; Nils Edvardsson; Nabil El Sherif; Mark Estes; Heidi Estner; Gerard Guiraudon; Sam Hanon; Richard Hauer; Bengt Herweg; Ellen Hoffman; Carsten Israel; Michiel Janse; Prapa Kanagaratnam; Helmut Klein; Yusuke Kondo; Jean-Yves Le Heuzey; Nicolas Lellouche; Thorsten Lewalter; Berndt Lüderitz; Marek Malik; Robert Myerburg; Yuji Nakazato; Brian Olshansky; Ali Oto; Eli Ovshyscher; Dubravko Petrac; Sanjeev Saksena; Walid Saliba; Massimo Santini; Peter Schwartz; Robert Schweikert; Dipen Shah; Claudio Shuger; Jasbir Sra; Gerhard Steinbeck; Neil Sulke; Richard Sutton; Tamas Szili-Torok; Jacob Tfelt-Hansen; Antonello Vado; Peter Van Tintelen; Reza Wakili; Albert Waldo; David Wilber; Bruce Wilkoff; Roger Winkle.

General Information

Congress Venue

LE MERIDIEN ETOILE Hôtel

81 Boulevard Gouvion Saint Cyr,

75848 Paris Cedex 17

Tel: (33) (0)1 40 68 34 34

www.lemeridienetoile.com

Congress Chairman

Nicolas Lellouche, MD Secretary:

Hôpital Henri Mondor

51 avenue du Maréchal

de Lattre De Tassigny

94000 Créteil, France

Email: nicolas.lellouche@hmn.aphp.fr

Sandrine Bordière

Tel: +33149 814350

Email: sandrinebordiere@hmn.aphm.fr

Abstract Awards

Abstracts for the best oral abstracts will be presented during the opening ceremony to take place on Sunday April 19, 2015, at Room Derain

Presentation of the awards for best poster presentations will take place on Tuesday April 21, 2015, 12:00 PM–12:30 PM Room Diderot (Meridien-Etoile Hotel) 11th Philippe Coumel Lecture 2015

Will be presented on Sunday April 19, 2015, from 5:30 PM to 6:00 PM as part of the opening ceremony

Badges

Badges and Final program will be available for pre-registered participants and faculty at the ECAS welcome desk, Hotel Meridien Etoile, Paris, starting Sunday April 19, 2015, from 2:00 PM to 6:00 PM

ECAS Congress Secretariat

Josette Razafimbelo

Tel/FAX: + 33 (0)4 89 14 45 33

Cell: +336 26 07 55 74

E-mail: josette.razafimbelo@sfr.fr

Registration

Registration and payment of Congress fees as well as payment of membership dues can be done through the website. Registration on site will start on Sunday April 19, 2015, at 8:00 AM at Hotel Meridien-Etoile.

Currency

Payment in cash for registration on site must be made in euros only. Payment using American Express or Visa credit cards will be accepted on the Congress site. Personal checks cannot be accepted.

Congress Website

All information, Scientific Program and registration to the congress, abstract submission and membership subscription with secured payment can be done through our website http://www.ecas-heartrhythm.org

Pre-Arranged Sessions

The program includes 33 pre-arranged sessions and workshops or debates. It can be downloaded from our website as well as the program of abstracts selected for oral or poster presentations

Publications

JICE (Journal of Interventional Cardiac Electrophysiology) is the official Journal of the European Cardiac Arrhythmia Society.

Sanjeev Saksena MD

JICE Editor-in-Chief

Leonardo Calo MD

ECAS JICE co-Editor

Abstract Presentations

The abstracts accepted for oral or poster presentation will be published in a supplement issue of the Journal of Interventional Cardiac Electrophysiology (JICE), the official journal of ECAS provided the authors attend the congress and present their work.

The oral presentation of abstracts is 10 min plus 5 min for discussion.

All posters accepted for presentation will be chaired. Please check the day and time at which your poster will be presented to the chairpersons and the time at which the presenter should be near their poster board.

SATURDAY APRIL 18, 2015

REGISTRATION from 2:00 PM to 5:00 PM

Hotel Meridien Etoile (Lobby)

SCIENTIFIC SESSIONS

SUNDAY APRIL 19, 2015

8:30 AM–10:00 AM

ROOM TBA

WS-06

Five Year Experience with NOACs: Time for a First Review

Chairpersons: Jean-Yves Le Heuzey (Paris, FR), Riccardo Cappato (Milan, IT)

1. NOACs in venous thromboembolism

Giancarlo Agnelli (Perugia, IT)

2. Stroke prevention of AF: Respective indications of NOAcs versus LAA device closure

Samuel Lévy (Marseille, France)

3. NOACs in catheter ablation

Wyn Davies (London, GB)

4. NOACs in cardioversion

Riccardo Cappato (Milan, IT)

SUNDAY APRIL 19, 2015

8:30 AM–10:00 AM

ROOM PASCAL

Workshop WS-01

Atrial Fibrillation Ablation: A New Generation of Approaches

Chairpersons: Douglas L. Packer (Rochester, USA), Karl-Heinz Kuck (Hamburg, DE)

1. Linear cold balloon therapy for persistent atrial fibrillation

Suraj Kapa (Rochester, USA)

2. Impact of Contact Force Ablation on Clinical Outcomes in Patients with Atrial Fibrillation

Dipen Shah (Geneva, CH)

3. 4–5 D Mapping for Intracardiac and Extracorporeal Ablation of AF

David Wilber (Maywood, USA)

4. The Biophysics of New Generation Cryoballoon and Contact Source Ablative Intervention

Douglas L. Packer (Rochester, USA)

SUNDAY APRIL 19, 2015

8:30 AM–10:00 AM

ROOM DIDEROT

Workshop WS-02

Cardiac Resynchronization Therapy

Improving Outcomes and Reducing Adverse events

Chairpersons: Bruce Wilkoff (Cleveland, USA), Helmut Klein (Munich, DE)

1. Pre-operative assessment of CRT Responsiveness

Bruce L. Wilkoff MD

2. Impact of RV pacing vs prevention of dyssynchrony

Jean-Jacques Blanc (Brest, FR)

3. Approaches to upgrading vs avoiding CRT

Mark Estes III (Boston, USA)

4. Management of atrial fibrillation in CRT Patients: PVI or AV junctional ablation

Walid Saliba (Cleveland, USA)

5. Alternatives to the CS for left ventricular pacing

Tamas Szili-Torok (Rotterdam, NL)

SUNDAY APRIL 19, 2015

8:30 AM–10:00 AM

ROOM DESCARTES

Workshop WS-03

Pacemaker ECG, ICD and CRT interpretation: Case studies

Chairpersons: Serge Barold (Tampa, USA), Eli Ovsyshcher (Beersheba, IL),

Carsten Israel (Bielefeld, DE), Bengt Herweg (Tampa, USA)

SUNDAY APRIL 19, 2015

8:30 AM–12:00 AM

ROOM GAUGUIN

Chaired poster session A

SUNDAY APRIL 19, 2015

10:30 AM–12:00 PM: Concurrent Abstract oral sessions

ROOM DERAIN

Abstract session 1

ROOM DIDEROT

Abstract session 2

ROOM DESCARTES

Abstract session 3

ROOM PASCAL

Abstract session 4

Luncheon Panels

12:15 PM–1:45 PM	12:15 PM–1:45 PM
Seated Luncheon Panel 1	Seated Luncheon Panel 2

SUNDAY APRIL 19, 2015

2:00 PM–3:30 PM

ROOM DERAIN

Session AB-01

Pulmonary vein isolation and related strategies

Chairpersons: Douglas Packer (Rochester, USA), Wyn Davies (London, GB)

1. AF mechanisms and role of pulmonary veins in various AF presentations

Karl-Heinz Kuck (Hamburg, DE)

2. Periprocedural dormant conduction after PV isolation: how does it affect AF recurrence?

Heidi Estner (Munich, DE)

3. Do catheter techniques make a difference in success rates?

Leonardo Calo (Rome, IT)

4. Role of autonomic ganglia in AF ablation success rates

Yusuke Kondo (Chiba, JP)

SUNDAY APRIL 19, 2015

2:00 PM–3:30 PM

ROOM DIDEROT

HD-01

Update on inherited potentially lethal syndromes

Chairpersons: Peter Schwartz (Pavia, IT), Hugh Calkins (Baltimore, USA)

1. Long QT syndrome

Peter Schwartz (Pavia, IT)

2. Cathecholaminergic polymorphic VT

Jacob Tfelt-Hansen (Copenhagen, DK)

3. Brugada syndrome

Herve Le Marec (Nantes, FR)

4. Early repolarization syndrome

Juhani Junttila (Oulu, FI)

SUNDAY APRIL 19, 2015

2:00 PM–3:30 PM

ROOM DESCARTES

SP-07

Joint session of ECAS-WSA (World Society of Arrhythmology)

The new frontiers in cardiac pacing

Chairpersons: Massimo Santini (Rome, DE), Eli Ovsyshcher (Beer Sheba, IL)

1. 50 years of cardiac pacing: where are we now?

João Rodrigues de Sousa (Lisbon, PT)

2. The leadless pacemaker

Antonio Curnis (Brescia, IT)

3. Multipoint pacing to optimize CRT outcome

Antonello Vado (Cuneo, IT)

4. Remote control: from device to patient management

Xavier Viñolas (Barcelona, ES)

5. Advances in biological pacing

Gerard Boink (Amsterdam, NL)

SUNDAY APRIL 19, 2015

2:00 PM–3:30 PM

ROOM PASCAL

Session SP-02

Prevention of sudden cardiac death in heart disease

Chairpersons: David Cannom (Los Angeles, USA), Poul Erik Bloch-Thomsen (Copenhagen, DK)

1. Effectiveness of Automatic External Defibrillators: availability and employability

Alessandro Capucci (Ancona, IT)

2. Indications and effectiveness of wearable ICDs

Johannes Brachmann (Coburg, DE)

3. What have we learned from prophylactic ICD trials?

Robert Myerburg (Miami, USA)

4. What have we learned from ICD registries?

Robert Hauser (Minneapolis, USA)

SUNDAY APRIL 19, 2015

2:00 PM–3:30 PM

ROOM GAUGUIN

Chaired Poster session B

3:30 PM–4:00 PM Coffee break and Posters

SUNDAY APRIL 19, 2015

4:00 PM–5:30 PM

ROOM DERAIN

Session AB-02

Issues in ventricular tachycardia ablation (I)

Chairpersons: Nicholas Peters (London, DE), Jasbir Sra (Milwaukee, USA)

1. New insights into the VT substrate using the Rhythmia System

Elad Anter (Boston, USA)

2. Functional characterization of VT scar by ripple mapping

Prapa Kanagaratnam (London, GB)

3. Epicardial ablation of VT

Katja Zeppenfeld (Leiden, NL)

4. Ablation of bundle branch and fascicular ventricular tachycardia

Jasbir Sra (Milwaukee, USA)

SUNDAY APRIL 19, 2015

4:00 PM–5:30 PM

ROOM DIDEROT

SP-03

The MADIT (Multicenter Automatic Defibrillator Implantation) Trials

Chairpersons: David Cannom (Los Angeles, USA), Luigi Padeletti (Florence, IT)

1. Long-term prognosis of MADIT-CRT patients: new data

Mark Estes III (Boston, USA)

2. MADIT-CHAGAS study: design and early data

Claudio Schuger (Detroit, USA) TBC

3. MADIT-CHIC study: design and early data

Jagmeet P. Singh, (Boston, USA)

4. Importance of LBBB in predicting a positive response to CRT therapy in Class I/II heart failure

David S. Cannom (Los Angeles, USA)

5. Impact of type II diabetes on the prognosis of coronary patients with heart failure: what would an ICD trial look like in this patient group?

Helmut Klein (Munich, DE)

SUNDAY APRIL 19, 2015

4:00 PM–5:30 PM

Room DESCARTES

SP-04

Advances in Intracardiac Imaging for Interventional Electrophysiologists: 2015 and beyond

Chairpersons: Andrea Natale (Austin, USA), Roger Winkle (Palo Alto, USA)

1. Cardiac CT for definition of left atrial appendage morphology and risk stratification

Luigi Di Biase (New York, USA)

2. Intracardiac echocardiography performed from and for the pulmonary vasculature—technique and application

Sanjeev Saksena (Warren, USA)

3. Magnetic resonance imaging of the atrial substrate and progression of atrial fibrillation: a critical analysis

Mark O’Neill (London, GB)

4. Real-time three dimensional imaging of cardiac chambers

Mohammad Shenasa (San Jose, USA)

SUNDAY APRIL 19, 2015

4:00 PM–5:30 PM

Room PASCAL

SP-05

Stroke prevention in atrial fibrillation

Chairpersons: John Camm (London, GB), Johannes Brachmann (Coburg, DE)

1. NOACs—5 years after RE-LY: What have we learned?

Michael Näbauer (Munich, DE)

2. Interventional therapy by occluder devices—which patients should be considered?

Thorsten Lewalter (Munich, DE)

3. Ablation therapy for stroke prevention in patients with AF

John Fisher (New York, USA)

4. Role of continuous rhythm monitoring—identification of cause or bystander?

Albert Waldo (Cleveland, USA)

SUNDAY APRIL 19, 2015

4:00 PM–5:30 PM

ROOM GAUGUIN

Chaired poster session B (Cont.)

Room DERAIN

5:30 PM to 6:00 PM

Special lecture: A tribute to Philippe Coumel TBA

Opening ceremony

Prof. Samuel Lévy (Marseille, FR) and Prof. Gerhard Steinbeck (Munich, DE) and

Outstanding Achievement Awards

Best Abstracts Awards

Presented by Dr Riccardo Cappato (Milan, IT)

President of ECAS

Prof. Nicolas Lellouche (Paris, FR)

Congress Chairman

Dr Fernand Hessel (Mulhouse, FR)

President Lucien Dreyfus Foundation

Followed by a cocktail reception

MONDAY APRIL 20, 2015

08:30 AM–10:00 AM

ROOM COROT

SESSION SP-06

Atrial Fibrillation: Beyond Stroke Prevention

Chairpersons: Nils Edvardsson (Gothenburg, SE), Amiran Revishvili (Moscow, RU)

1. Cardiovascular Morbidity and Mortality of AF

Christine Albert (Boston, USA)

2. Atrial Fibrillation and Sudden Cardiac Death

Eloi Marijon (Paris, FR)

3. Role of Pharmacology

Juan Tamargo (Madrid, ES)

4. Role of Catheter Ablation

Walid Saliba (Cleveland, USA)

MONDAY APRIL 20, 2015

08:30 AM–10:00 AM

ROOM DIDEROT

Session SP-07

Sudden cardiac death: Focus on at risk patients with secondary left ventricular hypertrophy (LVH)

Chairpersons: John Fisher (New-York, USA), Dubravko Petrac (Zagreb, HR)

ECG and MRI criteria of LVH

James Harrison (London, GB)

Mechanism of ventricular arrhythmias in patients with LVH

Nabil El-Sherif (New York, USA)

Risk stratification of patients with LVH at risk of sudden cardiac death

Gerhard Steinbeck (Munich, DE)

Regression of LVH and clinical outcome

Ariel Cohen (Paris, FR)

MONDAY APRIL 20, 2015

08:30 AM–10:00 AM

ROOM DESCARTES

Session HD-03

HRS-ECAS SPECIAL SESSION I

Arrhythmogenic Cardiomyopathy I

Diagnosis and Mechanisms

Chairpersons: Peter Van Tintelen (Amsterdam, NL), Connie Bezzina (Amsterdam, NL)

History of the disease

Guy Fontaine (Paris, Fr)

Advantages/limitations of the Revised Task Force Criteria

Frank Marcus (Tucson, Arizona)

Pathogenicity of genetic variants

Dennis Dooijes (Utrecht, NL)

Role of substructures in the Intercalated disk

Mario Delmar (New York, USA)

MONDAY APRIL 20, 2015

08:30 AM–10:00 AM

ROOM PASCAL

AB-03

Highly technologic approach in catheter ablation of complex arrhythmias

Chairpersons: Richard Schilling (London), Andrey Ardashev (Moscow, RU)

1. 3-D mapping and contact force sensing in ablation of atrial fibrillation

Roberto De Ponti, (Varese, IT)

2. Remote navigation ablation of atrial fibrillation and flutter using remote manipulation of multiple catheters

Eugene Crystal (Toronto, CA)

3. Preprocedural imaging and 3-D mapping in patients with ventricular tachycardia associated with structural heart disease

Richard Schilling (London, GB)

4. 3-D mapping and contact force sensing in ablation of idiopathic ventricular tachycardia

David Wilber (Chicago, USA)

MONDAY APRIL 20, 2015

08:30 AM–10:30 AM

ROOM GAUGUIN

Chaired Poster session C Part 1

10:00 AM–10:30 AM Coffee break and Posters

MONDAY APRIL 20, 2015

10:30 AM–12:00 PM

Concurrent Oral Abstract sessions

ROOM COROT

Abstract session 5

ROOM DIDEROT

Abstract session 6

ROOM DESCARTES

Abstract session 7

ROOM PASCAL

Abstract session 8

12:15 PM–1:45 PM Room Dufy	12:15 PM–1:45 PM
Luncheon Panel 3	Luncheon Panel 4

MONDAY APRIL 20, 2015

2:00 PM–3:30 PM

ROOM COROT

SESSION AB-04

Current issues in atrial fibrillation

Chairpersons: Antonio Raviele (Venice, IT), Olivier Piot (Paris, FR) TBC

Patients Selection: Do we already need updated guidelines?

Riccardo Cappato (Milan, IT)

Periprocedural Anticoagulation for AF ablation with warfarin and NOACs: beyond clinical stroke prevention

Etienne Aliot (Nancy, FR)

Energy Sources and tools: To whom, when and why?

New generation cryothermia balloon

Ellen Hoffmann (Munich, DE)

Laser balloon ablation

Thomas Deneke (Bad Neustadt, DE)

Lesion visualization and future directions

Matthew Wright (London, GB)

MONDAY APRIL 20, 2015

2:00 PM–3:30 PM

ROOM DIDEROT

SESSION: HD-06

Biomarker-based therapeutic decision making in atrial fibrillation

Chairpersons: Stefan Kääb (Munich, DE), Nicholas Peters (London, GB)

Biosignals—AF complexity guiding treatment strategies?

Ulrich Schotten (Maastricht, NL)

Biomarkers for the patient at risk for AF

Moritz Sinner (Munich, DE)

Genetics of AF—Ready for clinical decision making?

Stefan Kääb (Munich, DE)

MicroRNAs—Potential biomarkers for AF and AF therapy?

Reza Wakili (Munich, DE)

MONDAY APRIL 20, 2015

2:00 PM–3:30 PM

ROOM DESCARTES

HD-07

HRS-ECAS SPECIAL SESSION

ECAS-HRS Joint Special Session (organized by Richard Hauer)

Arrhythmogenic Cardiomyopathy II

Risk Stratification and Therapy

Cd Hauer (Utrecht, NL)

1. Electrophysiologic substrate and risk stratification

Alessandro Zorzi (Padova, IT)

2. Long-term Follow-up of ICD Therapy in ARVD/C

Hugh Calkins (Baltimore, Maryland)

3. Towards Elimination of the Electrophysiologic Substrate

Francis Marchlinski (Philadelphia, USA)

4. Towards New Drug Therapy

Jeffrey Saffitz (Boston, USA)

MONDAY APRIL 20, 2015

2:00 PM–3:30 PM

ROOM PASCAL

SP-15

Approaches in VT Ablation

Chairpersons: Francis Marchlinski (Philadelphia, USA), Walid Saliba (Cleveland, USA)

1. Mechanisms of VT in structural heart disease

Michiel Janse (Amsterdam, NL)

2. Ischemic cardiomyopathy: The homogenization approach

Andrea Natale (Austin, USA)

3. VT ablation in non-ischemic cardiomyopathy

Jasbir Sra (Milwaukee, USA)

4. The impact of pre and post VT ablation inducibility on long-term success, re-hospitalization and mortality.

Gerhard Hindricks (Leipzig, DE)

MONDAY APRIL 20, 2015

2:00 PM–5:00 PM

ROOM GAUGUIN

Chaired Poster presentation D

3:30 PM–4:00 PM Coffee break and Posters

MONDAY APRIL 20, 2015

4:00 PM–5:30 PM

ROOM COROT

AB-05

AF ablation techniques not targeting the pulmonary veins

Chairpersons: Riccardo Cappato (Milan, IT), David Wilber (Maywood, USA)

1. Detection and role of non-pulmonary vein AF triggers

Richard Schilling (London, GB)

2. Targeting complex fractionated atrial electrograms

Julien Seitz (Marseille, FR)

3. Mapping techniques for detecting rotors

Omer Berenfeld (Ann Arbor, USA)

4. Rotors-based AF ablation strategies

Sanjiv Narayan (San Diego, USA)

MONDAY APRIL 20, 2015

4:00 PM–5:30 PM

ROOM DIDEROT

SP-14

8th Japanese HRS/ECAS SYMPOSIUM

New Insights in CRT therapy

Chairpersons: Yuji Nakazato (Chiba, JP), Gilles Lascault (Paris, FR)

1. Impact of multisite LV pacing in heart failure patients

Werner Jung (Villingen, DE)

2. Trans-septal endocardial LV pacing

Hidemori Hayashi (London, GB)

3. Role of surgical approach: An update

Katsuhiko Imai (Hiroshima, JP)

4. Clinical efficacy of optimization algorithm

Toshiiyuki Ishikawa (Yokohama, JP)

MONDAY APRIL 20, 2015

4:00 PM–5:30 PM

ROOM DESCARTES

SP-13

Sudden cardiac death on a population level—Stratification methods for the patient with ejection fraction >35 %

Chairpersons: Stefan Kääb (Munich, DE), Brian Olshansky (Iowa City, USA)

1. Epidemiology of SCD

Xavier Jouven (Paris, FR)

2. ECG—Risk stratification for SCD

Pieter Postema (Amsterdam, NL)

3. Holter-ECG: Potential parameters for risk stratification

Marek Malik (London, GB) TBC

4. Genetics of SCD—What have we learned?

Vincent Probst (Nantes, FR)

MONDAY APRIL 20, 2015

4:00 PM–5:30 PM

ROOM PASCAL

HD-04

Role of the autonomic nervous system in cardiac arrhythmias

Chairpersons: Gunter Breithardt (Muenster, DE), Shlomo Ben Haim (London-GB)

1. Role of multimodal imaging in arrhythmia patients

Reza Wakili (Munich, DE)

2. Risk stratification by autonomic biosignaling

Axel Bauer (Munich, DE)

3. Role of sympathetic innervation in ARVD patients

Matthias Paul (Munich, DE)

4. Autonomic testing for risk stratification in Long-QT patients

Peter Schwartz (Milan, IT)

5. Renal Denervation—A treatment option for ventricular storm tachycardias

Noel Boyle (Los Angeles, USA)

MONDAY APRIL 20, 2015

4:00 PM–5:30 PM

ROOM GAUGUIN

Chaired Poster session D (Cont.)

MONDAY APRIL 20, 2015

5:30 PM–6:15 PM

ROOM COROT

Debate 1

Successful RF ablation alone is an acceptable treatment for monomorphic, well-tolerated VT with an ejection fraction above 30 %

Chairpersons: Francis Marchlinski, (Philadelphia, USA), Gerhard Steinbeck (Munich, DE)

Protagonist: Philippe Maury (Toulouse, FR)

Antagonist: Brian Olshansky (Iowa City, USA)

MONDAY APRIL 20, 2015

5:30 PM–6:15 PM

ROOM DIDEROT

Debate 2

Chairpersons: Berndt Lüderitz (Munich, DE), Pro Obel (Johannesburg, ZA)

Rhythm control in patients with atrial fibrillation should not be pursued vigorously in the post AFFIRM era?

Protagonist: A. John Camm (London, GB)

Antagonist: Sanjeev Saksena (Warren, USA)

MONDAY APRIL 20, 2015

5:30 PM–6:15 PM

ROOM PASCAL

Debate 3: Right ventricular apical pacing should be abandoned

Chairpersons: Luigi Padeletti (Florence, IT), Pascal Defaye (Grenoble, FR)

Protagonist: Carsten Israel (Bielefeld, DE)

Antagonist: Eli Ovsyshcher (Beer Sheba, IL)

TUESDAY APRIL 21, 2015

08:30 AM–10:00 AM

ROOM DIDEROT

Abstract session 9

ROOM DESCARTES

Abstract session 10

ROOM PASCAL

Abstract session 11

ROOM TBA

Abstract session 12

Coffee Break

TUESDAY APRIL 21, 2015

10:30 AM–12:00 AM

ROOM DIDEROT

Session SP-11

Unresolved questions in the management of cardiac arrhythmias

Chairpersons: Edward Rowland (London, GB), Maurice Khoury (Beirut, LB)

1. How to interpret short runs of AF on Holter monitoring?

Taya V. Glotzer (Hackensack, NJ, USA)

2. How much redo after a first AF ablation procedure?

David Keane (Dublin, IE)

3. Does revascularization prevent SCD?

Gerard Guiraudon (London, CA)

4. How safe are PVC’s in patients without structural heart disease?

Charles Jazra (Beirut, LB)

5. Ablation of PVCs: When and how?

Oussama Wazni (Cleveland, USA)

TUESDAY APRIL 21, 2015

10:30 AM–12:00 AM

ROOM DESCARTES

SP-12

New tools and techniques for AF therapy

Young German electrophysiologists—Session of the German EP Fellow program

Chairpersons: Reza Wakili Munich- DE, Roland Tilz (Hamburg DE)

1. Potential role of multimodal mapping for a better understanding of the AF substrate

Armin Luik (Karlsruhe, DE)

2. Role of continuous ECG monitoring by implantable loop recorders

Joern Schmitt (Giessen DE)

3. The nMARQ-catheter: initial experience and results

Stephanie Fichtner (Munich DE)

4. Rotor mapping: do different tools lead to different results?

Roland Tilz (Hamburg, DE)

TUESDAY APRIL 21, 2015

10:30 AM–12:00 AM

ROOM PASCAL

WS-04

Current Issues in AF management

Chairpersons: Roberto de Ponti (Varese, IT), Michiel Janse (Amsterdam, NL)

1. Remodelling and Anti-arrhythmic Agents

Dobromir Dobrev (Essen, DE)

2. Monitoring Ablation Outcomes—what really happens to AF?

Neil Sulke (Eastbourne, GB)

3. Thoracoscopic Surgery and Hybrid Therapy Outcomes

Alaadin Yilmaz (Amsterdam, NL)

4. Hot versus Cold—The latest outcomes of CRYO and RF techniques in paroxysmal and persistent AF

Ross Hunter (London, GB)

TUESDAY APRIL 21, 2015

10:30 AM–12:00 AM

ROOM TOCQUEVILLE

WS-05

Nightmares in catheter ablation: case presentations

Chairpersons: Riccardo Cappato (Milan), Ali Oto (Ankara, TR)

My worst case of…

1. Atrial flutter ablation

Isabel Deisenhofer (Munich)

2. Atrial fibrillation ablation

Nicolas Lellouche (Paris, FR)

3. Accessory pathway ablation

Peter Loh (Utrecht, NL)

4. Ventricular tachycardia ablation

Shigeru Ikeguchi (Kyoto, JP)

Abstract oral session 1: Atrial fibrillation ablation

Sunday, April 19, 2015, 10:30 AM–12:00 PM

1–1 Abstract 18–21

1 EFFECT OF ANTIARRHYTHMICS DRUG INITIATION ON READMISSION AFTER CATHETER ABLATION FOR ATRIAL FIBRILLATION

Peter Noseworthy¹, Holly Van Houten¹, Lindsey Sangaralingham¹, Abhishek Deshmuk¹, Suraj Kapa¹, Siva Mulpuru¹, Christopher McLeod¹, Samuel Asirvatham¹, Nilay Shah¹, Douglas Packer¹

¹ Mayo Clinic, Rochester, MN, United States

Background: Hospital readmission, a commonly tracked indicator of quality and efficiency of care delivery, occurs in about 15 % patients within 90 days of undergoing catheter ablation for atrial fibrillation (AF). We sought to evaluate the impact on antiarrhythmic drug (AAD) initiation on the risk of readmission. Methods and Results: Using a large national administrative claims database, we identified all atrial fibrillation patients (age ≥ 18 years) who underwent catheter ablation between 2005 and 2013. We identified the subset of patients who had not been on an AAD in the 90 days prior to the ablation (n = 2542) and, among those, the patients in whom an AAD was initiated within 7 days of the ablation (n = 826). A total of 387 (15.2 %) patients were readmitted within 90 days of ablation for any cause, and 161 (6.3 %) were readmitted with atrial fibrillation or atrial flutter as the primary discharge diagnosis. The readmission rate was significantly lower among patients who were initiated on an antiarrhythmic drug compared to those who were not (11.7 vs. 16.9 %, p = 0.0007). In a multivariate model, age 65+ years, Charlson index of ≥ 3, CHADS2 score of ≥ 3, and year of service in 2009–2010 were significantly associated with risk of readmission (p < 0.05). The association between antiarrhythmic drug initiation and reduced readmission persisted after adjustment for these variables (OR 0.84 [95 % CI 0.74–0.95], p = 0.0058). Amiodarone (HR 0.63 [0.42–0.95], p = 0.025) and class Ic agents (HR 0.65 [0.43–0.98], p = 0.04) were associated with the greatest reduction in readmission whereas dronedarone and class II agents had no statistically significant effect in time to event analysis. Conclusions: Initiation of an AAD within 7 days of catheter ablation is associated with a significant reduction in readmission within 90 days. Routine initiation of an AAD after catheter ablation may reduce health care utilization in the peri-ablation period.

1–2 Abstract 18–22

2 CONTACT FORCE DATA AVAILABILITY REDUCES ACUTE PULMONARY VEIN RECONNECTION: EARLY RESULTS FROM THE SMART AF TRIAL

Waqas Ullah¹, Ailsa McLean¹, Muzahir Tayebjee², Dhiraj Gupta³, Matthew Ginks⁴, Guy Haywood⁵, Mark O’Neill⁶, Pier Lambiase⁷, Mark Earley¹, Richard Schilling¹, Smart AF Trial Group UK⁸

¹ St Bartholomew’s Hospital, London, UK; ² Leeds General Infirmary, Leeds, UK; ³ Liverpool Heart and Chest Hospital, Liverpool, UK; ⁴ John Radcliffe Hospital, Oxford, UK; ⁵ Derriford Hospital, Plymouth, UK; ⁶ St Thomas’ Hospital, London, UK; ⁷ The Heart Hospital, London, UK; ⁸ Smart AF Trial Group, UK

BACKGROUND: Contact force (CF) sensing data may facilitate wide area circumferential ablation (WACA). We present data from an interim analysis of the first multicentre randomised controlled trial studying the impact of this data on the ablation of paroxysmal atrial fibrillation (PAF). METHODS: At seven UK centres, patients undergoing first-time PAF ablation were randomised to ablation with (CF-on) or without CF data (CF-off) available to the operator. Planned recruitment is 120 patients with 1-year follow-up. Using a 3D mapping system and the SmartTouch CF-sensing catheter (Biosense Webster), all patients underwent WACA. Subsequently a 1-h waiting time was observed before assessing acute pulmonary vein (PV) reconnection; if the PV remained isolated, 18 mg adenosine was administered intravenously. The primary end point was acute PV reconnection (spontaneous/adenosine induced). PVs were assessed separately, but cases of a common trunk were taken as one vein. PVs that appeared isolated but were assessed without completing the waiting period were excluded from the acute reconnection analysis. Follow-up is ongoing and 3-month outcomes are reported. RESULTS: One hundred sixteen patients have been recruited: age 59 ± 11 years, 57 % male, EHRA score 2.7 ± 0.6 and AF duration 37 [16–70] months (no significant baseline characteristic differences between groups). There were no differences in procedural parameters (Table). There was a significant, 40 %, reduction in acute PV reconnection in the CF-on group (Table). There were two tamponades and one minor pericardial effusion in the CF-on group, and one minor hematoma in the CF-off group. Ninety patients (43 CF-off, 47 CF-on) have completed 3-month follow-up: at this point, there is no difference in EHRA scores (CF-off 1.6 ± 0.6, CF-on 1.5 ± 0.6, p = 0.8).

	CF-off group	CF-on group	p value
Number	60	56
Total procedure time (min)	195 [165–216]	193 [171–219]	0.97
Total fluoroscopy time (min)	13 [6–23]	10 [6–30]	0.96
Total fluoroscopy dose (cGy.cm2)	904 [292–1684]	813 [365–2187]	0.88
Total radiofrequency ablation rime (s)	2446 [1898–2862]	2446 [2023–2956]	0.46
Total pulmonary vein acute reconnections	68/227 (30 %)	38/202 (18 %)	0.01
Left pulmonary vein acute reconnections	35/115 (30 %)	17/103 (17 %)	0.017
Right pulmonary vein acute reconnections	33/112 (30 %)	21/99 (21 %)	0.2

CONCLUSIONS: Addition of CF sensing data had no impact on procedure, fluoroscopy or ablation times, but did reduce acute PV reconnection rates, suggesting more effective ablation application and consequently more durable PV isolation. Whether this translates to improved long-term success will be assessed on study completion.

1–3 Abstract 18–26

3 PAROXYSMAL ATRIAL FIBRILLATION ABLATION WITHOUT PULMONARY VEIN ISOLATION

Clement Bars¹, Julien Seitz², Guillaume Theodore³, Ange Ferracci², Michel Bremondy², Jacques Faure², André Pisapia²

¹ Institut Mutualiste Montsouris, Paris, France; ² Hôpital Saint Joseph, Marseille, France; ³ University Hospital, Nice, France

Background: Pulmonary vein isolation (PVI) is the most popular approach for paroxysmal atrial fibrillation (PAF) ablation. This method is a probabilistic one and do not specifically target AF substrate which could lead either to under- or over-treatment. Objectives: We aimed to evaluate in PAF an electrogram substrate ablation technique guided by regional high-density mapping. Methods: We analysed the PAF subgroup of the SUBSTRATE HD study (multicentric study with seven operators involved). Twenty-four patients undergoing PAF ablation were thus prospectively enrolled for a first ablation procedure (mean age = 61.7 + 10.25). A substrate biatrial highdensity mapping with a 20-pole-contact electrode PentaRay NAV catheter (Biosense Webster) was performed. AF substrate was detected both automatically with a new CFAE algorithm setting and visually by operators (continuous CFAE and temporal gradient of activation). Ablation end points were AF termination (sinus rhythm or atrial tachycardia conversion), sinus conversion and non-inducibility (“atrial devulnerabilisation”). Results: AF was induced in 16 patients (66.6 %) by rapid atrial pacing. The median mapping times and number of acquisition points/patient in the right and left atria were, respectively, as follows: 7 [4–7] and 14 [9.25–15] min with 569 [285–739] and 831 [1052–490] points. Substrate ablation without PVI terminated AF in 23/24 (96 %) patients in 15.3 + 14.8 mean min RF time. Sinus rhythm was restored in 23/24 (96 %) patients and non-inducibility was achieved in 75 %. The total mean procedure and RF time were, respectively, 153.9 + 36 and 43 min +18.4. No procedural complications occurred. After a mean follow-up of 6.5 + 2.8 months 23/24 (96 %), patients were free from AF and 19/24 (79.16) were free from any atrial arrhythmias. Conclusion: Electrogram-based substrate ablation guided by bi-atrial high-density mapping for PAF without PVI is feasible, safe, reproducible and efficient.

1–4 Abstract 18–16

4 PREDICTION OF AF ABLATION OUTCOME: THE CAAP-AF SCORE

Roger Winkle¹, Julian Jarman², R. Hardwin Mead¹, Gregory Engel¹, Melissa Kong¹, William Fleming¹, Rob Patrawala¹

¹ Silicon Valley Cardiology, E Palo Alto, CA, USA; ² Royal Brompton Hospital, London, UK

Objectives: To develop a clinical scoring system to predict the final outcome for all patients undergoing atrial fibrillation (AF) ablation. Methods: We examined a development cohort (DC) of 1125 consecutive patients undergoing 1.34 ± 0.53 AF ablations from 2003 to 2010. Results: Pt. demographics were as follows: age = 62.3 ± 10.3, male = 71.2 %, LA size = 4.30 ± 0.69 cm, paroxysmal AF 30.9 %, drugs failed = 1.3 ± 1.1, hypertension = 46.7 %, diabetes = 8.9 %, prior CVA/TIA = 6.9 %, prior cardioversion = 46.9 % and CHADS2 = 0.87 ± 0.97. Multivariate analysis showed six independent variables predicting outcome after final ablation: CAD (p = 0.021), atrial diameter (p = 0.0003), age (p = 0.004), persistent or longstanding AF (p < 0.0001), antiarrhythmic drugs failed (p < 0.0001) and female (p = 0.0001). We created a scoring system (CAAP-AF) using these six variables with total CAAP-AF scores ranging from 0 to 13 points. CAAP-AF Score: CAD = 1 pt; atrial diameter <4.0 = 0 pts, 4 to <4.5 = 1 pt,.4.5 to <5 = 2 pts, 5.0 to <5.5 = 3 pts, ≥ 5.5 = 4 pts; age <50 = 0 pts, 50 to <60 = 1 pt, 60 to <70 = 2 pts, ≥70 = 3 pts; persistent or longstanding AF = 2 pts; antiarrhythmic drugs failed none = 0 pts, 1 or 2 = 1 pt, ≥3 = 2 pts; female = 1 pt. CAAP-AF score predicted final outcome (C statistic = 0.691, p = 0.0006). The 2-year Kaplan-Meier AF free rates by CAAP-AF scores were as follows: 0 = 100 %, 1 = 95.7 %, 2 = 96.3 %, 3 = 83.1 %, 4 = 85.5 %, 5 = 79.9 %, 6 = 76.1 %, 7 = 63.4 %, 8 = 51.1 %, 9 = 53.6 % ≥10 = 29.1 %. Cochran-Armitage trend test showed worsening 2-year outcome with higher CAAP-AF scores (p < 0.0001). The CAAP-AF score was then applied prospectively to 937 patients in a test cohort (TC) undergoing AF ablation from 2010 to 2012. The CAAP-AF score also predicted final outcome in the TC (C statistic = 0.651, p = 0.009). The 2-year Kaplan-Meier AF free rates by CAAP-AF scores were as follows: 0 = 100 %, 1 = 87.0 %, 2 = 89.0 %, 3 = 91.6 %, 4 = 90.5 %, 5 = 84.4 %, 6 = 70.1 %, 7 = 71.0 %, 8 = 60.7 %, 9 = 68.9 % ≥10 = 51.3 %. Cochran-Armitage trend test showed worsening 2-year outcome for the TC with higher CAAP-AF scores (p < 0.0001). Conclusions: An easily determined clinical scoring system was derived retrospectively and applied prospectively. CAAP-AF predicted the final outcome of AF ablation in both a development and a test cohort of AF ablation patients. CAAP-AF may provide a realistic AF ablation outcome expectation for individual pts.

1–5 Abstract 18–32

5 A COMBINED APPROACH OF POINT BY POINT RADIOFREQUENCY ABLATION FOLLOWED BY CRYOBALLOON ABLATION DRAMATICALLY IMPROVES THE RATE OF LONG TERM PULMONARY VEIN ISOLATION FOR PATIENTS WITH PAROXYSMAL AF

Richard Ang¹, Aaisha Opel¹, Waqas Ullah¹, Victoria Baker¹, Malcolm Finlay¹, Mehul Dhinoja¹, Mark Earley¹, Simon Sporton¹, Richard Schilling¹, Ross Hunter¹

¹  St Bartholomew’s Hospital, London, UK

Introduction: In a randomized controlled trial, patients undergoing first-time paroxysmal AF ablation were randomized to pulmonary vein (PV) isolation by wide-area circumferential ablation with radiofrequency energy (RF), cryoballoon (CRYO), or RF followed by CRYO (COMBINED). We report the long-term PV reconnection rates and sites. Methods: In patients who had a recurrence of AF, a repeat procedure was offered. A duodecapolar PV mapping catheter was used to identify whether each PV had reconnected. In a subset from each group, the sites of PV reconnection were prospectively defined during ablation as sites where ablation caused a change in PV activation sequence or PV isolation (>1 site possible per PV) and were categorized into one of eight segments (figure). Results: Two hundred thirty-four patients entered the study, and at a median follow-up of 41 (IQR 30–51) months, only 17/79 (22 %) in the COMBINED group required a repeat procedure compared with RF 38/77 (49 %) and CRYO 33/78 (42 %), both p < 0.01, with no significant difference between RF and CRYO alone, p = 0.42. In the COMBINED group, 6/17 (35 %) had no PV reconnected, compared to only one in the RF and none in the CRYO groups, both p < 0.01. The number of PVs reconnected per patient was also lower (1.2 vs. 2.5 RF and 2.3 CRYO, both p < 0.01). The frequency of reconnections for each PV and the PV reconnection sites for 25 consecutive cases in the CRYO and RF groups and 10 cases for the COMBINED group are presented in the figure. Conclusions: A combined approach dramatically reduces long-term PV reconnection and the need for repeat procedures compared to either RF or CRYO. The PV reconnection pattern differs between CRYO and RF and may explain the synergistic effect of the combined approach.

1–6 Abstract 18–25

6 USE OF CONTACT FORCE TECHNOLOGY IN AF ABLATION PROCEDURES DOES NOT IMPROVE CLINICAL OUTCOME RATES—INSIGHTS FROM A 3 YEAR SINGLE CENTER EXPERIENCE

Stefan Sattler¹, Johannes Siebermair¹, Eva Klocker¹, Lucia Olesch¹, Samira Saraj¹, Ina Klier¹, Christoph Schuhmann¹, Sebastian Clauss¹, Moritz Sinner¹, Stephanie Fichtner¹, Stefan Kääb¹, Heidi Estner¹, Reza Wakili¹

¹ Medical Department I, Klinikum Grosshadern, Ludwig-Maximilians-University, Munich, Germany

Introduction: Pulmonary vein isolation (PVI) is an established method to treat atrial fibrillation (AF). Contact force (CF) sensing catheters have been introduced with the purpose to improve procedural parameters and clinical outcome of AF ablation. In this study, we evaluated >300 PVI procedures regarding the role of CF catheters with respect to procedural parameters and mid-term clinical outcome. Methods: We performed an analysis of a total of 302 patients with paroxysmal (n = 141) or persistent AF (n = 161) undergoing PVI; patients were divided into two groups: (1) n = 158, ablation performed with CF sensing SMARTtouch catheter© (ST) aiming for a CF > 10 g/lesion, and (2) n = 144, patients undergoing PVI with a standard ablation catheter (SAC). Complete electrical isolation of all PVs was considered as procedural endpoint (PE). FU was performed on regularly basis by 7-day ECG Holter recordings in 6 months terms. Results: Patient characteristics regarding percentage of paroxysmal AF, male gender, age, LA size, LV ejection fraction, history of hypertension or concomitant structural heart disease did not differ significantly between both groups. PE was reached in all patients. Application of CF measurement feature in the ST group did result in a significant reduction of whole procedure time (232 ± 151 vs. 269 ± 57 min, **p < 0.01), lower number of energy applications (33 ± 17 vs. 38 ± 17, **p < 0.01) and a decreased fluoroscopy time (29 ± 14 vs. 47 ± 27 min, **p < 0.01) compared to the SAC group. However, analysis of clinical outcome (freedom from AF) revealed no significant difference between both groups during a mean FU period of 254 ± 178 days (74 % ST vs. 73 % SAC, ns, see figure). Conclusions: Our results suggest that the use of CF catheters show a beneficial effect on procedural parameters but failed to result in an improved clinical outcome over time.

Abstract oral session 2: Sudden cardiac death: prevention and management

Sunday, April 19, 2015, 10:30 AM–12:00 PM

2–1 Abstract 10–13

7 OUTCOME OF PATIENT WITH EARLY REPOLARIZATION AFTER UNEXPLAINED SYNCOPE

Mathieu Le Bloa¹, Frederic Sacher¹, Jean-Baptiste Gourraud², Philippe Maury³, Gabriel Laurent⁴, Christophe Leclercq⁵, Jacques Mansourati⁶, Dominique Babuty⁷, Jean-Luc Pasquié⁸, Pierre Jais¹, Nicolas Derval¹, Arnaud Denis¹, Meleze Hocini¹, Michel Haïssaguerre¹, Vincent Probst²

¹CHU Bordeaux, Bordeaux, France; ² CHU Nantes, Nantes, France; ³CHU Toulouse, Toulouse, France; ⁴CHU Dijon, Dijon, France; ⁵CHU Rennes, Rennes, France; ⁶CHU Brest, Brest, France; ⁷CHU Tours, Tour, France; ⁸CHU Montpellier, Montpellier, France

Background: Early repolarization (ER) is a common finding in the general population (5 %). It has been reported to increase the risk of arrhythmic death. We sought to compare incidence of ventricular tachycardia (VT) and/or sudden cardiac death (SCD) after unexplained syncope without cardiomyopathy, on patients with or without ER. Methods: From January 2009 to December 2013, all patients hospitalized for unexplained syncope, presenting J wave elevation ≥0.1 mV in at least two inferior (II, III, aVF) and/or lateral leads (V4–V6, I, aVL) from 23 centers, have been included in a prospective registry. Their outcome was compared with patient admitted in University Hospital of Bordeaux on the same period, without cardiomyopathy nor ER. Referring physicians managed the patients according to their local practice. Results: One hundred patients were included in ER group (84 (84 %) males, 33 ± 16.5 years old), 53 (53 %) received an implantable loop recorder (ILR). During a mean follow-up of 31.8 ± 17.9 months, and 11 (11 %) experienced a ventricular arrhythmia (10 VT (figure) and 1 SCD). In the group without ER (n = 139, 84 (60 %) males, 51 ± 19 years old), 70 (50.4 %) had an ILR. During a mean follow-up of 36.8 ± 19.7 months, 4 (2,8 %) had a ventricular arrhythmia (2 VT and 2 SCD). ER was associated with an increased hazard ratio (HR) for ventricular arrhythmia of 5.07 (IC95 % [1.61–16.0], p = 0.03) and 4.55 (IC95 % [1.17–17.8], p = 0.029) when adjusted on sex. In ER group, only inferior ER was associated with arrhythmia. J wave amplitude, ER pattern, ST segment aspect, regional and transmural dispersions of repolarization were not associated with a different outcome. Conclusions: ER pattern after an episode of unexplained syncope is associated with an increased risk of ventricular arrhythmia.

2–2 Abstract 19–24

8 DAYTIME AND SEASON AS PREDICTORS FOR CARDIAC RHYTHM DISTURBANCES IN DIFFERENT DISEASES—A LARGE REAL-LIFE ANALYSIS

Eimo Martens¹, Johannes Siebermair¹, Regina Freeden², Carsten Koenig², Stefan Veith¹, Moritz Sinner¹, Stefan Kääb¹

¹ Klinikum der Universität München, Muenchen, Germany; ² Medtronic GmbH, Meerbusch, Germany

Background. SCD underlies until now a not-understood circadian rhythm during the day and during the year. Only for a small part of the SCD predictors are known. Implantable cardioverter-defibrillator (ICD) systems are well established to prevent sudden cardiac death (SCD). It is important to understand the predictors for rhythm disturbances to identify patients at risk for SCD. Objective. The objective of this analysis was to retrospectively investigate the temporal distribution of rhythm disturbances of ICD patients in dependence of clinical patient parameters. Methods. Anonymized follow-up data of ICD and CRT-D of the time between 2002 and 2014 were collected and pooled from our clinic. Data were analyzed in a database that allows the collection of follow-up from ICD programmer as well as telemedicine transmissions. Within the database, all parameters as well as EGMs, episode- and patient-data is stored and can be analyzed. Physicians classified the occurrence of appropriate vs. inappropriate therapy or episode type. Results. Data were analyzed from 8300 follow-ups of 704 patients (952 ICD/CRT-D devices). We specified 79 % male, mean age 66 ± 13 years, 62,7 % primary prevention, 55 % ICM, 39 % DCM and 6 % other diseases. We detected 4888 episodes overall, thereof 1369 with relevant rhythm disturbances. Eight hundred ninety-nine VT episodes (median cycle length 409 ms) and 470 VF episodes (median cycle length 231 ms) were found. For VF episodes, we could find a significant peak around 8 pm (p = 0.03, Fig. 1) for primary and secondary prevention patients. For VT episodes, it was in contrast to the overall distribution a significant peak found in ICM patients in the early morning (p = 0.02, Fig. 2). During the year, we found significant higher incidence of VF and VT episodes in April (primary and secondary prevention) and September/October (secondary prevention) (Figs 3 and 4). In ischemic patients, significantly more episodes occur in April; patients with dilative cardiomyopathy showed significant higher incidence of episodes in September (Fig. 3). Conclusion. ICD patients have relevant VT and VF episodes during their life. Underlying disease and the difference between primary and secondary prevention cause significant different distribution of VF and VT episodes during the day and the year. It is the duty of further investigations to investigate the daily or yearly predictors for the higher incidence rate.

2–3 Abstract 19–25

9 RANOLAZINE AMELIORATES POST-RESUSCITATION ELECTRICAL INSTABILITY AND MYOCARDIAL DYSFUNCTION AND IMPROVES OUTCOME IN A RAT MODEL OF VENTRICULAR FIBRILLATION

Francesca Fumagalli¹, Ilaria Russo¹, Lidia Staszewsky¹, Roberto Latini¹, Antonio Zaza², Giuseppe Ristagno¹

¹ IRCCS-Istituto di Ricerche Farmacologiche “Mario Negri”, Milan, Italy; ² Dipartimento di Biotecnologie e Bioscienze, Università degli Studi Milano-Bicocca, Milan, Italy

Dysregulation of intracellular Ca2+ homeostasis plays a critical role in the pathophysiology of cardiac arrest and cardiopulmonary resuscitation (CPR), leading to ventricular arrhythmias and left ventricle (LV) dysfunction. We investigated the effects of the INaL blocker ranolazine on outcome of CPR. Methods. Eighteen rats were assigned to receive intravenous ranolazine, 10 mg/kg, or vehicle. Ventricular fibrillation (VF) was then induced and untreated for 8 min. CPR was then performed for 8 min. ECG, arterial, and right atrial pressures were monitored up to 3 h after CPR. LV function was monitored by echocardiography, and 72-h survival was evaluated. Incidence, frequency, and duration of ventricular arrhythmias were quantified. Effects of ranolazine on VF waveform features were assessed by measuring the amplitude spectrum area (AMSA), peak (PF), median (MDF), mean frequency (MNF), and root mean square amplitude (RMS). Results. All animals in the ranolazine group were resuscitated and survived up to 72 h, whereas 72 % in the vehicle group were resuscitated and 54 % survived. AMSA and RMS were consistently higher in animals pretreated with ranolazine (p < 0.01 vs. vehicle). PF, MNF, and MDF during untreated VF, and MNF and MDF during CPR, were significantly lower in the ranolazine group. Successful resuscitation was immediately followed by a period of severe arrhythmias, including VPBs and runs of VT and VF, leading to hemodynamic instability. The presence of arrhythmias, including any type of arrhythmic episode, was observed in 100 % of rats in the vehicle group, in contrast to only 43 % of rats in the ranolazine group (p < 0.03). The number of VPBs and VTs, and duration of VTs, was greater in rats resuscitated in the vehicle group, compared to rats pretreated with ranolazine. This period of arrhythmias lasted more than 11 min in vehicle animals and less than 3 min in ranolazine ones (p < 0.02). At 10 min after resuscitation, heart rate, mean arterial pressure, and CPP were significantly higher in the ranolazine group (p < 0.05 vs. vehicle). No differences in the duration of PR, QRS, and QT electrocardiographic intervals were observed between the two study groups, except for a transient increase in QT duration in the ranolazine group prior to onset of VF (p < 0.01). Seventy-two hours after resuscitation, LV systolic and diastolic functions were better in ranolazine group (p < 0.05 vs. vehicle). Full neurological recovery was observed in all ranolazine animals, while neurological impairment persisted in vehicle ones (p < 0.02). Conclusion. Ranolazine pretreatment reduced post-resuscitation electrical and hemodynamic instability and improved post-resuscitation LV function and survival.

2–4 Abstract 19–16

10 FOLLOW-UP OF PATIENTS WITH IDIOPATHIC VENTRICULAR FIBRILLATION (THE FU-IVF STUDY)—PRELIMINARY RESULTS

Marloes Visser¹, Charlotte Siegers¹, Jeroen van der Heijden¹, Peter Loh¹, Pieter Doevendans¹, Rutger Hassink¹

¹ UMC Utrecht, Utrecht, Netherlands

Background: Idiopathic ventricular fibrillation (IVF) is the underlying cause of 5–10 % of out-of-hospital cardiac arrest patients. IVF is defined as VF without structural or electrical heart disease present upon first presentation. Little is known regarding long-term outcome and clinical characteristics during follow-up of IVF patients. The purpose of this study is to further elucidate underlying causes and to more accurately assess the prognosis. Methods: This retrospective cross-sectional study describes the follow-up of 100 IVF patients diagnosed since 1985. IVF diagnoses were reassessed and reclassified if needed according to current guidelines. Additional testing (e.g. ajmalin-testing, echocardiography, genetic testing) was performed if needed. Genetic testing was performed with a custom gene panel containing 33 genes associated with VF and cardiomyopathy. Results: Fifty-nine males and 41 females were included, with a mean age at event of 41.6 years. A previous history of syncope was reported in 24 % of patients. Ninety patients (90 %) received an ICD, of which 36 % (32/90) received appropriate ICD therapy. During a mean follow-up of 10 years, diagnosis was revised in 18 % of patients (e.g. to structural disease such as arrhythmogenic and dilated cardiomyopathy or electrical disease such as Brugada and long QT syndrome). A genetic diagnosis was obtained in 11 patients. The all-cause mortality was 13 %. Conclusion: Our results show a high mortality and recurrence rate of ventricular arrhythmia requiring ICD-therapy in IVF patients. A substantial amount of patients initially diagnosed with IVF reveal an underlying structural or electrical heart disease during follow-up, with VF as first manifestation. These data emphasize the importance of comprehensive follow-up of IVF-patients, regarding its impact on patient diagnosis, treatment and genetic- and family counselling. Keywords: Follow-up, Idiopathic Ventricular Fibrillation

2–5 Abstract 19–26

11 BENEFITS OF ICD THERAPY: CONNECTING TREATMENT DECISIONS TO INDIVIDUALIZED SCD RISK ESTIMATES WITHIN SCD-HEFT—SEATTLE PROPORTIONAL RISK MODEL

Wayne Levy¹, Jeanne Poole¹, Anne Hellkamp², Ramin Shadman³, Todd Dardas¹, Jill Anderson⁴, George Johnson⁴, Daniel Fishbein¹, Daniel Mark², Kerry Lee², Gust Bardy⁴

¹ University of Washington, Seattle, WA, USA; ² Duke University, Durham,NC, USA; ³ Southern California Permanente Medical Group, Los Angeles, CA, USA; ⁴ Seattle Institute for Cardiac Research, Seattle, WA, USA

Introduction. Currently, there is no method to predict if a patient dies, the likelihood that the death will be a sudden death (potentially preventable with an ICD) vs. a non-sudden death. Hypothesis. We developed the Seattle Proportional Risk Model (SPRM) to predict the proportion of death that is due to sudden death in 9985 patients using age, gender, EF, NYHA, SBP, Na, Cr, digoxin use, BMI, and diabetes. We prospectively tested this model in the patients enrolled in SCD-HeFT to determine the extent to which ICD benefit for sudden death and all-cause mortality would vary based on the predicted proportional risk of sudden death. We tested the concept that a patient with a higher estimated proportion of sudden death will benefit more from an ICD than a similar patient with a lower estimated proportion of sudden death (i.e. 70 vs. 40 %). Methods. A Cox proportional hazards model was used to determine if the ICD benefit varied by the SPRM. Results. In a Cox proportional hazard model, the adjusted ICD benefit for all-cause mortality (27 %, p = 0.0016) and sudden death (62 %, p < 0.0001) was as anticipated, consistent with the primary results of SCD-HeFT. However, the ICD benefit varied markedly with the SPRM for both sudden death (interaction p < 0.0001) and all-cause mortality (interaction p = 0.0003) with markedly greater benefit of the ICD in patients with a higher predicted proportion of sudden death. The ICD reduction in sudden death from lowest to highest SPRM quartiles (low to high proportion sudden death) was 19, 57, 78, and 95 % (p = 0.55, 0.02, 0.007, and 0.003, respectively). The ICD benefit varied markedly for all-cause mortality across SPRM quartiles from a 10 % increase in the 1st quartile to decreases of 28, 47, and 66 % in the 2nd to 4th quartiles (p = 0.38, 0.055, 0.01, 0.001, respectively). Conclusions. Although a primary prevention ICD in SCD-HeFT reduced sudden death by 62 % and all-cause mortality by 27 %, the benefit is not uniform. In SCD-HeFT, the reduction in sudden death and all-cause mortality was confined to those with a higher proportional risk of sudden death, whereas patients in the lowest quartile of SPRM risk had no mortality benefit from the ICD. The SPRM can be a real-time tool to identify individuals who are most appropriate for a primary prevention ICD.

2–6 Abstract 19–30

12 IMPLANTABLE CARDIAC DEFIBRILLATOR IN THE SETTING OF TETRALOGY OF FALLOT

Abdeslam Bouzeman¹, Guillaume Duthoit², Magalie Ladouceur¹, Raphael Martins³, Maxime De Guillebon⁴, Laurent Fauchier⁵, Pascal Defaye⁶, Jean-Baptiste Gourraud⁷, Jean-Marc Sellal⁸, Pierre Mondoly⁹, Fabien Lalombarda¹⁰, Frederic Anselme¹¹, Linda Koutbi¹², Nicolas Lellouche¹³, Franck Halimi¹⁴, Anne Messali¹⁵, Amel Mathiron¹⁶, Nicolas Sadoul⁸, Laurence Iserin¹, Pierre Bordachar⁴, Nicolas Combes¹⁷, Jean-Benoit Thambo⁴, Eloi Marijon¹

¹Paris Cardiovascular Research Center, Inserm U970, Paris, France/European Georges Pompidou Hospital, Paris, France/Paris Descartes University, Paris, France; ²CHU La Pitie Salpetriere Hospital, Cardiology Department, Paris, France; ³CHU Pontchaillou, Cardiology Department, Rennes, France; ⁴CHU Haut Leveque, Cardiology Department, Bordeaux, France; ⁵CHU Trousseau, Tours, France; ⁶CHU Michallon, Grenoble, France; ⁷CHU Nantes, Nantes, France; ⁸CHU Brabois, Nancy, France; ⁹Hopital Rangueil, Toulouse, France; ¹⁰ CHU Caen, Caen, France; ¹¹CHU Rouen, Rouen, France; ¹²CHU La Timone, Marseille, France; ¹³CHU Henri Mondor, Creteil, France; ¹⁴Hopital Prive Parly II, Le Chesnay, France; ¹⁵CHU Bichat, Paris, France; ¹⁶CHU Amiens, Amiens, France; ¹⁷Clinique Pasteur, Toulouse, France

Background—Tetralogy of Fallot (TOF) is the most frequent form of congenital heart disease managed by EP physicians for potential implantable cardioverter defibrillator (ICD). However, few studies have reported long-term outcomes of TOF patients with ICD. Methods—Between 2005 and 2014, all TOF patients with ICD in 17 French centers were enrolled in a specific evaluation aiming to determine characteristics at implantation as well as outcomes (overall mortality, appropriate ICD therapies, and device-related complications). Results—Overall, 78 patients were enrolled with a mean age at implantation of 45 ± 13 years. Fifty patients (64 %) were male. A majority of patients were implanted in the setting of secondary prevention (73 %), whereas the remaining (27 %) in primary prevention. Among the latest group, characteristics, known as risk factors of appropriate therapy, were observed as follows: important pulmonary regurgitation in 30 %, prior palliative shunt in 50 %, syncope with unknown origin in 25 %, inducible ventricular tachycardia in 45 %, QRS duration ≥180 ms in 18 %, non-sustained ventricular tachycardia in 25 %. In addition, 45 % had documented sustained supra ventricular tachycardia, and 30 % presented symptoms of heart failure. Twenty-eight patients (37 %) finally received a single-chamber ICD, 37 patients (49 %) dual chamber and 8 patients (11 %) had ICD with resynchronization therapy. After a mean follow-up of 4.9 ± 3.8 years, 35 patients experienced at least one appropriate therapy (45 %): 25 % appropriate therapy in the primary prevention group compared to 53 % of patients in the secondary prevention group (P = 0.45). The mean time between ICD implantation and the first appropriate therapy was 2.2 ± 3.2 years. Overall, ≥one ICD-related complication occurred in 30 patients (38 %), including inappropriate shock (n = 9), major pocket hematoma (n = 1), lead dysfunction (n = 12), infection (n = 4), shoulder algodystrophia (n = 2), device failure or dislodgement needing reintervention (n = 2). Eventually, four patients were transplanted (5 %), and six patients (8 %) died during the course of follow-up (including two without previous appropriate therapy). Conclusions—Considering relatively long-term follow-up, patients with TOF and ICDs experience high rates of appropriate ICD therapies, in both primary and secondary prevention. Major ICD-related complications remain, however, high. Selection of candidates, especially for primary prevention implantation, remains challenging and may be improved in the future.

Abstract oral session 3: Atrial fibrillation and prevention of related thromboembolism

Sunday, April 19, 2015, 10:30 AM–12:00 PM

3–1 Abstract 15–25

13 PERSISTENT LEFT ATRIAL APPENDAGE THROMBUS IN NON-VALVULAR ATRIAL FIBRILLATION AND RISK OF THROMBOEMBOLISM

Omer Iqbal¹, Yassar Nabeel¹, Hardik Doshi¹, Lee Joseph¹, Prashant Bhave¹, Miriam Zimmerman¹, Michael Giudici¹

¹ University of Iowa Hospitals and Clinics, Iowa City, IA, USA

Background: In patients with non-valvular atrial fibrillation (NVAF), a transoesophageal echocardiogram (TEE) is usually performed to rule out left atrial appendage (LAA) thrombus prior to initiating rhythm control, in order to reduce the risk of thromboembolism (TE). When thrombus is detected by TEE, a repeat study is often performed after 3–4 weeks of continuous oral anticoagulation in order to document resolution of the thrombus prior to restoring sinus rhythm. There are few data assessing TE risk in patients with NVAF who have TEE which document thrombus. We conducted this study to quantify the TE risk in such patients. Methods: A single-center retrospective review identified 65 patients with NVAF who were found to have LAA thrombus on TEE and had a CHA2DS2VASCscore of at least 1 between 2002 and 2014. Depending on subsequent TEE findings, they were divided into three groups: patients with persistent LAA thrombus (PLAAT) [N = 15], resolved LAA thrombus (RLAAT) [N = 13], and unknown LAA thrombus evolution (ULAAT) in patients with no repeat TEE [N = 37]. TE event rates per person-year and all-cause mortality in these groups were assessed. Results: Median follow-up was 1.93 years (PLAAT), 1.91 years (RLAAT), and 0.49 years (ULAAT). Actual thromboembolic events/person-year were 4.2 (ULAAT), 0.36 (PLAAT), and 0.03 (RLAAT). The ULAAT group had higher TE event rates when compared to PLAAT (p = 0.006) or RLAAT (p < 0.0001); however, comparing event rate between PLAAT and RLAAT, there was no significant difference (p < 0.115). After adjustment for CHA2DS2VASC score, results did not differ. There was no significant difference in overall mortality between three groups (p = 0.48); however, 1-year mortality rates in each group were very high: 29 % for ULAAT, 14 % for PLAAT, and 8 % for RLAAT. Conclusions: In patients with no repeat TEE to ensure resolution of LAA thrombus, there was an increased TE risk and increased mortality rate compared to those with persistent or resolved LAA thrombus. This finding could be related to how closely patients were followed up and treated in the RLAAT and PLAAT groups. This finding could also be related to the fact that patients in the ULAAT group did not receive repeat TEE because of their overall severity of illness.

3–2 Abstract 15–57

14 FEASIBILITY AND SAFETY OF UNINTERRUPTED PERI-PROCEDURAL APIXABAN ADMINISTRATION IN PATIENTS UNDERGOING RADIOFREQUENCY CATHETER ABLATION FOR ATRIAL FIBRILLATION: RESULTS FROM A MULTICENTER STUDY

Luigi Di Biase¹, Dhanujaya Lakkireddy², Chintan Trivedi³, Thomas Deneke⁴, Martin Martinek⁵, Sanghamitra Mohanty³, Prasant Mohanty⁶, Sameer Prakash⁷, Rong Bai³, Carola Gianni⁸, Rodney Horton⁵, Elisabeth Sigmund⁵, Michael Derndorfer⁴, Anja Schade⁹, Patrick Mueller¹⁰, Atilla Szoelloes⁵, Javier Sanchez³, Amin Al-Ahmad³, Patrick Hranitzky⁵, G. Joseph Gallinghouse⁵, Richard H. Hongo⁵, Salwa Beheiry¹⁰, Helmut Puererfellner⁵, Andrea Natale³

1 . Texas Cardiac Arrhythmia Institute at St David’s Medical Center and Albert Einstein College of Medicine at Montefiore Hospital, Austin and New York, TX, USA 2 . University of Kansas Medical Center, Kansas City, KS, USA 3. Texas Cardiac Arrhythmia Institute at St. David’s Medical Center, Austin, TX, USA 4. Heartcenter Bad Neustadt, Bad Neustadt, Germany 5. Elisabethinen Linz GmbH, University Teaching Hospital, Linz, Austria 6. Texas College of Osteopathic Medicine, Fort worth, TX, USA 7. Tong Ji Hospital Tong Ji Medical College Hust, Wuhan, China 8. Texas Cardiac Arrhythmia Research, Austin, TX, USA 9. Northern California Heart Care, San Francisco, CA, USA 10. California Pacific Medical Center, San Francisco, CA, USA

Introduction: Periprocedural anticoagulation management with uninterrupted warfarin with a “therapeutic INR” represents the best approach reducing both thromboembolic and bleeding complications in the setting of catheter ablation for atrial fibrillation (AF). The purpose of this study was to evaluate the safety and feasibility of uninterrupted apixaban administration in this setting.

Methods: We performed a prospective multicenter registry of AF patients undergoing radiofrequency catheter ablation at four Institutions in the USA and Europe with an uninterrupted apixaban strategy. These patients were compared with an equal number of patients, matched for age, gender, and type of AF, undergoing AF ablation on uninterrupted warfarin.

The apixaban group comprised consecutive patients who were on twice-daily 5 mg Apixaban for at least 30 days prior to ablation. The last dose of apixaban was taken the morning of the procedure. A subset of 29 patients underwent dMRI to detect silent cerebral ischemia (SCI) in the apixaban group.

Results: A total of 400 patients (200 patients in each group) were included in the study. The average age was 65.9 ± 9.9 years with 286 (71.5 %) male and 334 (83.5 %) patients having non-paroxysmal AF. There were no differences in major (1 vs. 0.5 %,p = 1.0), minor (3.5 vs. 2.5 %,p = 0.56), and total bleeding complications (4.5 vs. 3 %,p = 0.43) between the apixaban and the warfarin group, respectively. There were no symptomatic thromboembolic complications. All the dMRIs were negative for SCI in the apixaban group.

Conclusions: Uninterrupted apixaban administration in patients undergoing AF ablation appears to be feasible and effective in preventing clinical and silent thromboembolic events without increasing the risk of major bleedings.

3–3 Abstract 15–28

15 HYPERACUTE AND CHRONIC CHANGES IN CEREBRAL MAGNETIC RESONANCE IMAGES AFTER PVAC, NMARQ AND EPICARDIAL THORACOSCOPIC SURGICAL ABLATION FOR PAROXYSMAL ATRIAL FIBRILLATION

Conn Sugihara¹, Neil Barlow¹, Emma Owens¹, David Sallomi¹, Steve Furniss¹, Neil Sulke¹

¹ East Sussex Healthcare NHS Trust, Eastbourne, UK

Background: Asymptomatic cerebral events (ACEs) detected with cerebral MRI immediately post AF ablation have been reported with a number of AF ablation techniques. Methods: Patients ablated with either PVAC, nMARQ or thoracoscopic epicardial surgical AF ablation had cerebral MRIs performed before, immediately after and 3 months after ablation. All MRIs were independently reported by three radiologists blinded to treatment assignment, in two phases. Firstly, MRIs were anonymised, randomised and examined individually. Then, each patient’s MRIs were compared in sequence to look for new changes. Results: Fifty-four patients (mean age 65 years, median CHA2DS2-Vasc score 2) were analysed. Sixty-five percent of patients received an immediate post-ablation MRI. Prior to ablation, although no patient had a prior history of cerebral infarction (CI), 15.6 % of patients had MRI evidence of CI, and 84.4 % had white matter change (WMC). Of all scans, 8.3 % were reported to have a lesion consistent with an ACE. However, most ACEs appeared on the baseline or 3-month scans, hence were not ablation-related. Once MRIs were compared in sequence, two ACEs on the hyperacute scan were shown to be pre-existing. There were two (13.3 %) PVAC patients, one (6.7 %) nMARQ patient and no surgical patients with ablation-related ACE. Three months after ablation, there were no new CIs detected, but 43 % of patients had evidence of progressive white matter change. No patient had any clinical neurological abnormality detected at any time during the study period. Conclusions: There was a high background rate of asymptomatic cerebral lesions in patients undergoing AF ablation. The majority of ACEs were not ablation-related. Cerebral MRIs in AF patients demonstrated a very high rate of both baseline undocumented, and rapidly progressive, asymptomatic cerebrovascular disease. The clinical relevance of cerebral MRI changes in AF ablation remains unclear.

3–4 Abstract 15–51

16 RIVAROXABAN AND TWO DOSAGES DABIGATRAN VERSUS WARFARIN IN PATIENTS WITH HIGH RISK OF STROKE AND EMBOLISM UNDERGOING ELECTRICAL CARDIOVERSION WITH PERSISTENT AND LONG-ACTING ATRIAL FIBRILLATION

Oskars Kalejs¹, Olga Litunenko², Aldis Strelnieks³, Sandis Sakne¹, Milana Zabunova¹, Marina Kovalova⁴, Galina Dormidontova⁵, Iveta Sime⁶, Natalija Pontaga⁵, Kaspars Kupics¹, Maija Vikmane¹, Janis Guslens⁷, Aivars Lejnieks³, Andrejs Erglis¹

¹ P. Stradins Clinical University Hospital, Riga, Latvia; ² Riga Stradins University, Riga, Latvia; ³ Riga East University Hospital, Riga, Latvia; ⁴ Jelgava Regional Hospital, Jelgava, Latvia; ⁵ Daugavpils Regional Hospital, Daugavpils, Latvia; ⁶ Liepaja Regional Hospital, Liepaja, Latvia; ⁷ Riga Technical University, Riga, Latvia

Background. The important factor of safety in patients with atrial fibrillation (AF) undergoing electrical cardioversion (ECV) is appropriate use of oral anticoagulants (OAC). Novel anticoagulants (NOAC) are a possible alternative to warfarin. Methods. We have analysed the data in 1512 patients (pts) undergoing ECV. One thousand one hundred ninety-three AF defined as persistent and 319 as long-standing mean CHA2 DS2 VASc score was 3.6 ± 1.9; 1025 had one or two ECV in history. Nine hundred seventy-three (64.3 %) pts started the use of NOAC: dabigatran (D) 405 pts 150 mg twice or 302 pts 110 mg twice or 266 rivaroxaban (R) 20 mg daily before ECV for at least 21 days, 539 (35.6 %) started warfarin (W) and 21 days start after INR was in range 2.0–3.0. One hundred ten milligrams twice were prescribed for pts ≥ 75 years old, HASBLEED risk score ≥3 and kidney problems. Transoesophageal echocardiography (TEE) was encouraged before ECV in all groups for pts with CHA2DS2VASc score ≥ 4, left atrial dilatation and AF duration ≥ 6 months. ECG and echo data were analysed 30 and 90 days after ECV. Results. ECV was successful after first shock in 1239 (92 %) pts, total success ECV—in 1318 (97.9 %) pts. Left atrial thrombi were detected on TEE before ECV in 31 pts in NOAC group and 28 pts in W group, so pts continued OAC therapy for 2 months and TEE had been performed again. Nine pts in D (150 mg twice), 6 pts in R (20 mg od) group and 5 pts in W group were free of thrombus and have been referred for ECV. Average time of treatment before ECV was significantly lower for NOAC (25 days) than with W (48 days, p < 0.01). Stroke and systemic embolism at 90 days were lower in the NOAC group (0.1 %) than in the W group (1.5 %). The events in the NOAC group were documented after discontinuation of the drug while in the W group, eight events were detected during the use of OAC. There was no difference in analysis of events between TEE and non-TEE pts in D and R. NOAC pts had significantly lower clinical relevant bleeding rate vs W (D 110 mg 0, D 150 mg 0.47 %, R 0.39 % vs W 2.87 %, p < 0.04). Conclusions. Dabigatran 150 and 110 mg twice and rivaroxaban 20 mg daily are a safe, effective and reasonable alternative to warfarin for patients undergoing ECV despite high CHA2DS2VASc risk score, HASBLEED score and AF duration. The frequencies of stroke and embolic events were lower in the dabigatran 150 and 110 mg and rivaroxaban 20 mg than in the warfarin group with lower major bleeding within 30 and 90 days after ECV. Patients on NOAC’s had a shorter anticoagulation period before cardioversion.

3–5 Abstract 15–36

17 SINUS RHYTHM AND QUALITY OF LIFE IN THE AGE OF MODERN THERAPIES FOR ATRIAL FIBRILLATION: RESULTS FROM THE PREFER IN AF REGISTRY

Liang-han Ling¹, Hunter Ross¹, Waqas Ullah¹, Alex Breitenstein¹, Finlay Malcolm¹, Aaisha Opel¹, Sarah Horan¹, Bernd Brüggenjürgen², Harald Darius³, Raffaele De Caterina⁴, Kamran Iqbal⁵, Jean-Yves Le Heuzey⁶, Paulus Kirchhof⁷, Josef Schmitt⁸, Jose Luis Zamorano⁹, Richard Schilling¹

¹ St Bartholomew’s Hospital, London, UK; ² Steinbeis-University, Institute for Health Economics, Berlin, Germany; ³ Vivantes Hospital, Berlin, Germany; ⁴ University Chieti-Pescara, Cardiology, Pisa, Italy; ⁵ Daiichi-Sankyo UK Ltd, Gerrards Cross, UK; ⁶ Georges Pompidou Hospital, René Descartes University, Paris, France; ⁷ University of Birmingham, Birmingham, UK; ⁸ Daiichi-Sankyo, Munich, Germany; ⁹ University Hospital Ramón y Cajal, Madrid, Spain

Background: Clinical determinants of quality of life (QoL) in AF have been poorly investigated. We evaluated these in a large cross-sectional study and compared QoL measures between patients on vitamin K antagonists (VKAs) versus the novel oral anticoagulants (NOACs dabigatran, rivaroxaban, and apixaban). Methods: The PREFER in AF registry (Prevention of Thromboembolic Events—European Registry in Atrial Fibrillation) enrolled 7243 consecutive AF patients aged above 18 years from centres in seven European countries from January 2012 to January 2013. Socio-demographic data, co-morbidities, AF characteristics, and therapies were evaluated for independent predictors of EuroQol-5D-5L (EQ-5D-5L) index value, an overall questionnaire-based measure of QoL, using simple and multiple logistic regression. Paired comparisons between matched patients taking VKAs versus NOACs (396 per group) were made of (i) EQ-5D-5L component scores, (ii) Perception of Anticoagulant Treatment Questionnaire 2 (PACT-Q2) measures of satisfaction and convenience, (iii) GP and cardiologist outpatient encounters, and (iv) working days lost to AF. Results: Reduced EQ-5D-5L index value (≤0.84) was independently associated with the following: age >75 years (OR 2.32), female gender (OR 1.80), unskilled occupation (OR 1.25), diabetes (OR 1.34), congestive heart failure (OR 1.24), coronary artery disease (CAD, OR 1.35), prior ischaemic stroke (OR 1.64), obesity (OR 1.41), left ventricular systolic dysfunction (OR 1.42), EHRA maximum score of 4 (OR 2.53), and therapy with amiodarone (OR 1.40) (p < 0.01 in all cases). Sinus rhythm at assessment independently predicted higher EQ-5D-5L score >0.84 (OR 1.5, p < 0.001). NOAC therapy was associated with greater convenience and satisfaction than VKA therapy, by PACT-Q2 measures (p < 0.01). No significant differences in EQ-5D-5L index value, its subcomponent scores, GP and cardiologist outpatient encounters, or working days lost to AF, were found between matched VKA and NOAC users. Conclusion: Maintenance of sinus rhythm is associated with higher QoL in AF patients, even after accounting for the independent effects of multiple socio-demographic factors and comorbidities. Efforts to maintain SR, other than with the use of amiodarone, may be of importance in improving QoL in the patient subgroups most likely to be underserved—the elderly, women, those of lower socioeconomic background, and those with cardiovascular comorbidities. NOAC therapy is associated with greater convenience and satisfaction over the use of VKAs in a general AF population, but in this analysis was not associated with greater overall QoL.

3–6 Abstract 15–33

18 PRIMARY PERIPHERAL ARTERY EMBOLISM: ATRIAL FIBRILLATION RELATED RISK-STRATIFICATION AND RECURRENT EMBOLIC EVENTS DURING LONG-TERM FOLLOW-UP.

Christian Möllenhoff¹, Dirk Bastian², Athanasios Katsargyris¹, Konrad Göhl², Eric L. G. Verhoeven¹

¹ Paracelsus Medical University, Nuremberg Hospital, Dept. of Vascular and Endovascular Surgery, Nuremberg, Germany; ² Paracelsus Medical University, Nuremberg Hospital, Dept. of Cardiology/Rhythmology, Nuremberg, Germany

Acute peripheral ischemia of the upper extremity [API] is a disease with standardized procedure in diagnostic and therapy in vascular surgery. In addition to specific vascular therapy, one has to search for the source of the embolus. In most cases, the embolus originates from the heart, due to structural or rhythmological diseases. When atrial flutter or fibrillation [AF] is detected, the indication for permanent oral anticoagulation [OAC] is given. Chad2sVasc2-Index supports risk stratification and decision making. But without the proof of AF, the level of cardiologic and rhythmologic investigations is uncertain, also the need for OAC. The aim is to evaluate the incidence of recurrent embolic events during long-term follow-up after primary API and its correlation with AF-associated risk factors. We analysed hospital records of patients with API referred to our department in 2005 for the diagnosis of peripheral embolisation, stroke, heart rhythms, cardiac disorders and vascular diseases. Medical course as well as surgical therapy and medication at discharge were documented. Additionally, we screened our hospital database for recurrent embolic events up to 2013. In 2005, 16 patients attended our hospital with the diagnosis of API (mean age 73.6 years ±0.6a). At admission, the surface electrocardiogram [ECG] showed AF in 10 patients; 6 patients were in sinus rhythm [SR]. In 10 out of 16 patients, a transthoracic echocardiography for embolus screening was performed; no patient with SR received a long-term-ECG [TL-ECG] to rule out AF. Mean Chad2sVasc2-Score was 3.62 ± 2.0 over all, and 3.67 ± 1.97 in SR group. While patients with AF received OAC, SR patients were treated only with acetylsalicylic acid [ASS] 100 mg/day. During follow-up period, recurrent embolic events occurred in 4 of 6 patients in SR group: 2 cases of embolisation of the upper extremity, 1 stroke, 1 transitoric ischemic attack. At the time of the recurrent event, 3 of 4 patients were in SR, in one nothing was documented. One was under therapy of ASS; no patient was treated with OAC. Our retrospective study shows that examination for the source of embolic events in patients with API is inadequate. Patients with peripheral embolism have a high risk according to the Chad2sVasc2-Score. During long-term follow-up, the rate of recurrent embolic events is high, even if SR is documented. Therefore, a prospective trial with long-term follow-up is needed to evaluate the efficiency of a standardized diagnostic work-up including LT-ECG and a risk adopted anticoagulation strategy for secondary prevention of recurrent embolic events.

Abstract oral session 4: Mechanisms of ventricular arrhythmias

Sunday, April 19, 2015, 10:30 AM–12:00 PM

4–1 Abstract 01–12

19 PREVALENCE OF RIGHT VENTRICULAR ENDOCARDIAL BIPOLAR LATE POTENTIALS IN BRUGADA SYNDROME

Luigi Sciarra¹, Ermenegildo De Ruvo¹, Chiara Lanzillo¹, Alessio Borrelli¹, Antonio Scarà¹, Marco Rebecchi¹, Alessandro Fagagnini¹, Marta Marziali¹, Lucia De Luca¹, Domenico Grieco¹, Ludovica Scialla², Elisa Salustri³, Annamaria Martino¹, Leonardo Calò¹

¹ Cardiologia - Policlinico Casilino, Italia, Italy; ² Cardiologia - Policlinico Umberto I, Rome, Italy; ³ Cardiologia - Università de L’Aquila, L’Aquila, Italy

Introduction: Brugada syndrome (BS) is considered to be an “electrical” disease in structurally normal hearts. The electrophysiological substrate of the syndrome is not clarified. Late potentials (LPs) are bipolar signals occurring after the QRS complex and have been identified as good target for VT ablation in structural heart disease. Delayed ventricular activity has been identified in a limited population of symptomatic BS patients at the anterior epicardial aspect of the right ventricular outflow tract (RVOT). Aim of our study: We aim to assess the presence of endocardial right ventricular LP in a BS population. Methods: We studied 10 patients (mean age 38 ± 13 years; 7 males) with BS. Diagnosis of BS was based on the typical ECG alterations: 9 patients showed spontaneous “type 1” pattern; in 5 patients ,we observed a coved type pattern after flecainide infusion. Control group: Eight patients (mean age 47 ± 17 years; six males) without structural heart disease undergone to an ablation for atrio-ventricular nodal re-entrant tachycardia. Every subject underwent to right ventricular electroanatomical mapping with the Carto3 system (Biosense Webster). Low-voltage areas are areas with a local voltage >1.5 and <0.5 mV. Scar areas are areas with a local voltage <0.5 mV and absence of ventricular capture with 10 V of output. LPs were defined as bipolar signals recorded after QRS termination. Results: LPs were present in 6 patients with BS (60 %) and in none of the controls (p < 0.01). The number of collected points was comparable in both groups (198 ± 83 in BS vs 181 ± 42 in controls; p = NS). In all cases, LPs were found in the RVOT tract: 4 anterior, 1 posterior and 1 septal RVOT. In all cases, LP areas were coincidence or in proximity of low-voltage or scar areas. In the 4 patients without LP, we did not find any low-voltage or scar area. All patients with BS and evidence of LP showed a type 1 pattern ECG patter at the time of endocardial mapping. Conclusions: Endocardial bipolar LPs are common in patients with BS and are mainly located at the RVOT. Our results need to be confirmed in larger series and could be important for future therapeutical developments in high risk BS pts.

4–2 Abstract 02–11

20 SLOWING OF CONDUCTION VELOCITY VIA GAP-JUNCTIONAL UNCOUPLING IS SUFFICIENT TO CAUSE ELECTROGRAM FRACTIONATION

Shaun Selvadurai¹, Emmanuel Dupont¹, Caroline Roney¹, Norman Qureshi¹, Fu Siong Ng¹, Rasheda Chowdhury¹, Nicholas Peters¹

¹ Imperial College London, London, UK

Electrogram fractionation is commonly used to identify areas of abnormal electrical activity to guide catheter ablation. Cellular mechanisms for this fractionation remain largely unknown. In silico modelling questions whether cell-cell coupling can lead to fractionation. We aimed to investigate if conduction slowing by cellular uncoupling alone was sufficient to lead to an increase in electrogram fractionation in an in vitro simple cell model. A monolayer of HL-1 cell line myocytes was seeded onto 8 × 8 microelectrode arrays (100 mm electrodes/ 700 mm spacing) and loaded with voltage sensitive dye di-8-ANEPPS. Carbenoxolone (gap-junction uncoupler) was administered in incremental doses (0–50 μM). After 5 min of stabilisation, electrogram recordings were taken while optical images were simultaneously recorded. Administration of carbenoxolone resulted in up to 65 % conduction slowing (p < 0.001), with a significant increase in fractionation seen between 30, 40, and 50 μM compared to baseline (p < 0.05). Linear regression showed a significant correlation (p < 0.001) between conduction velocity and percentage of fractionation (r ² = 0.5773). Reduced electrogram amplitude (p < 0.05) and increased duration (p < 0.05) was seen with slower conduction, though no significant change in total area under the curve (AUC) was seen. Action potential duration (APD) remained unchanged. A correlation was found between cell-cell uncoupling-induced conduction slowing and proportion of electrogram fractionation; supporting current computer models. The unchanged AUC and APD suggest ion exchange remains unaltered. We have shown that conduction slowing via cell-cell uncoupling may be sufficient for electrogram fractionation.

4–3 Abstract 01–16

21 GAP JUNCTION UNCOUPLING DURING ISCHAEMIA ACTIVATES NORMALLY QUIESCENT PURKINJE-MYOCARDIAL JUNCTIONS RESULTING IN MORE COMPLEX ACTIVATION PATTERNS

Fu Siong Ng¹, Elham Behradfar², Michael T Debney¹, Anders Nygren², Adam Hartley¹, Alexander Lyon¹, Igor Efimov³, Edward Vigmond⁴, Nicholas S Peters¹

¹ Imperial College London, London, UK; ² University of Calgary, Calgary, Canada; ³ Washington University in Saint Louis, Saint Louis, MO, USA; ⁴ Universite Bordeaux 1, Bordeaux, France

Introduction: The His-Purkinje system activates ventricular myocardium through Purkinje-myocardial junctions (PMJs). It has been suggested that most PMJs are normally non-functional at baseline due to source–sink mismatches at these junctions. We hypothesised that gap junctional uncoupling at the PMJs during acute ischaemia facilitates propagation across a greater number of functional PMJs, thereby leading to accelerated but more complex activation patterns. Methods: In aortic-perfused rabbit hearts (n = 8), the right ventricles (RV) were exposed, preserving the Purkinje system (Figure), and the endocardium optically mapped. Activation of the RV endocardium during atrial pacing was recorded during 40 min of global ischemia followed by 30 min reperfusion. A corresponding detailed 3D computer model of rabbit ventricles with Purkinje system was also constructed to test the hypothesis. Results: Optical mapping studies revealed that the percentage of RV area activated within the first 5 ms decreased from baseline 53 ± 6 to 43 ± 8 % during early ischemia (<20 min), and paradoxically then increased to 59 ± 8 %, with more complex activation (p < 0.001). This coincided with more surface breakthroughs at more PMJs during late ischaemia (Figure). Activation normalised after reperfusion. In the computer model, a 6 % reduction in conductivity was sufficient to render quiescent PMJs active. Increasing the fraction of functioning PMJs from 5 to 100 % accelerated endocardial activation from 27.1 to 15.8 ms, compensating for reduced conduction velocity. Surface breakthroughs increased, as did the complexity of activation, matching the experiments. Conclusion: At baseline, most PMJs are quiescent. Ischaemia-induced closure of gap junction channels reduces conduction velocity, but as the uncoupling progresses, more PMJs become functional due to reduced source–load mismatch. The altered, more complex, activation patterns during ischaemia may be pro-arrhythmic as they increase the pathways for meandering wavefronts and the likelihood of wave collision.

4–4 Abstract 02–14

22 CELLULAR CHARACTERISATION OF STROMAL CELL AND CARDIOMYOCYTE COUPLING AT THE CRITICAL ISTHMUS IN AN IN VIVO SWINE MODEL OF POST-INFARCTION RE-ENTRANT VENTRICULAR TACHYCARDIA

Tarvinder Dhanjal¹, Nicolas Lellouche², Chris Von Ruhling¹, David Edwards¹, Chris George¹, Alan Williams¹

¹ Wales Heart Research Institute, Cardiff, UK; ² Henri Mondor Hopital, Paris, France

Introduction: Electroanatomical- and MRI-based mapping techniques have defined the critical isthmus (CI) in the post-myocardial infarction (MI) re-entrant VT circuit as heterogeneous areas of myocardium within the scar border zone (BZ). In vitro studies show myofibroblast-cardiomyocyte (MFB-CM) coupling results in slow conduction, a pre-requisite for re-entry. However, the nature and extent of functional coupling between MFBs and CMs in vivo remains controversial. We have performed a comprehensive evaluation of the structural relationship between surviving CMs and stromal cells at the VT CI. Methods: All studies are performed according to the position of the European Union Directive 2010/63/EU and approved by the Animal Care and Use Committee of the Centre Hospitalier Universitaire Henri Mondor (INSERM U955). Domestic pigs underwent MI induction. The VT study was performed after 6 weeks with a substrate, pace and entrainment mapping approach to identify scar, BZ, CI, late potentials and LAVAs. Electroanatomic-histological overlay was achieved with three epicardial location points assigned to the map and markers sutured at the corresponding locations prior to explantation and histological analysis. Results: Table 1 shows voltage characteristics of VT-inducible (n = 6) and non-inducible (n = 6) pigs. Histological analysis was focused on five distinct regions: (1) VT CI sites, (2) BZ regions not VT CI, (3) LAVAs, (4) dense scar and (5) normal myocardium. Immunohistological analysis assessed cell-type-specific markers identifying CMs, MFBs and fibroblasts with regional extracellular matrix composition. Furthermore, the distribution and magnitude of connexin (37, 40, 43 and 45) and cadherin (pan, OB and N) coupling between MFBs and cardiomyocytes was defined. Conclusion: This study demonstrates key electrophysiological and histological differences in the post-infarct VT inducible heart and novel insights in the cellular composition and architecture of the VT CI which forms the basis for further molecular investigation which may lead to improved VT CI targeting for catheter ablation.

Table 1. Characterisation of post-MI myocardium associated with non-inducible and inducible VT

	Non-inducible VT (n = 6)	Inducible VT (n = 6)	p value
CARTO points (n ± sSE)	454 ± 112	393 ± 50	0.34
LV mass (g)	146 ± 3	145 ± 14	0.87
Voltage area bipolar <2 mV (cm2)	27 ± 12	26 ± 4	0.52
Voltage area bipolar <1 mV (cm2)	16 ± 7	10 ± 1	0.005
Border zone area (cm2)	11 ± 5	17 ± 3	0.055
Border zone area (% of scar)	41 ± 3	64 ± 2	0.004

4–5 Abstract 01–233

23 THE DEVELOPMENT OF A NOVEL SYSTEM FOR THE STUDY OF CARDIAC ARRHYTHMIA—SIMULTANEOUS MEASUREMENT OF CALCIUM TRANSIENTS AND ELECTRICAL ACTIVITY IN MURINE CARDIAC TISSUE

Alastair Yeoh¹, Malcolm Finlay², Naomi Anderson³, Stephen Harmer³, Andrew Tinker³

¹ UCL and QMUL, London, UK; ² Barts Health NHS Trust and QMUL, London, UK; ³ QMUL, London, UK

Introduction: More effective diagnosis and treatment of cardiac arrhythmia requires a deeper understanding of the underlying pathophysiology of arrhythmia. Existing research primarily employs single-cell or whole-heart models, but there is a translational gap between these levels of study. This study describes the development of a novel system to simultaneously measure calcium and electrophysiology at the tissue level, intended to bridge the gap between cell and organ research. Methods: A combined calcium fluorescence and solid-state electrical recording system was set up on an inverted microscope. Samples of murine tissue were loaded with a fluorescent calcium indicator dye (Fluo-4AM). Intracellular calcium transients (elicited by electrical stimulation via external electrodes) were recorded by a CMOS digital camera, which measured emission light from samples excited with a narrow wavelength LED. The validity of this calcium imaging system was assessed by measuring the effects of decreased cycle length and pharmacological agents on calcium transients. Electrical and fluorescence data were then obtained simultaneously. Electrical data were recorded by contact electrodes in a multi-electrode array. Results: Tissue was successfully loaded with fluorescent dye and calcium transients (observed as increases in green fluorescence, Figure) elicited by electrical stimulation were recorded. Calcium transient height and duration decreased by 19 % (p < 0.001) and 16 ms (95 % CI 13–20), respectively, when coupling intervals were reduced from 400 to 200 ms (n = 5). Isoprenaline 100 nm reduced calcium transient length by 10 ms (95 % CI 4.8–16) (n = 5). Increasing concentrations of nifedipine showed a dose-dependent decrease in calcium transient size. Calcium fluorescence transients were successfully measured in tandem with electrical activity. Conclusion: The current study describes the successful development of a calcium fluorescence imaging system and its integration into a multi-electrode array recording system. This system provides a novel multi-parametric tool for the study of arrhythmia in cardiac tissue.

4–6 Abstract 17–13

24 MELATONIN AND OMACOR INCREASE THRESHOLD TO INDUCE VF AND NORMALIZE MYOCARDIAL CONNEXIN-43 EXPRESSION IN FEMALE RATS EXPOSED TO HIGH SUCROSE DIET.

Tamara Benova¹, Csilla Viczenczova¹, Jana Radosinska², Vladimir Knezl³, Barbara Bacova¹, Jana Navarova³, Branislav Obsitnik⁴, Jan Slezak¹, Narcisa Tribulova¹

¹ Institute for Heart Research, Slovak Academy of Sciences, Bratislava, Slovakia; ² Institute of Physiology, Faculty of Medicine, Comenius University, Bratislava, Slovakia; ³ Institute of Experimental Pharmacology & Toxicology, Slovak Academy of Sciences, Bratislava, Slovakia; ⁴ St. Elisabeth Institute of Oncology, Bratislava, Slovakia

Rationale and purpose: Abnormal localization and/or dysfunction of cardiac connexin-43 (Cx43) channels have been implicated in the occurrence of life-threatening arrhythmias. Our previous studies indicate that diabetes is associated with Cx43 and PKC-epsilon alterations linked with slower conduction. To elucidate the impact of glucose metabolism disorders on development of Cx43 alterations and susceptibility of the heart to inducible VF, we examined female rats that underwent high sucrose diet. Moreover, we tested antiarrhythmic effects of melatonin and Omacor® and possible implication of Cx43 in this condition. Design and methods: The experiment was performed on 9-month-old female Wistar rats that were divided into four groups: (1) controls, (2) rats drinking 30 % sucrose solution (HSD), (3) HSD supplemented with melatonin (40 μg/ml in drinking water) and (4) HSD supplemented with omega-3 fatty acids (Omacor, 25 g/kg per diet). Left ventricle was used for analysis of Cx43 mRNA and protein levels as well as protein expression of PKCÎμ (which phosphorylates Cx43) and PKCÎ’ (which is implicated in pro-apoptotic signaling). Electrically inducible sustained VF was examined using isolated-perfused heart. Results: High sucrose diet resulted in an increase of body weight, adiposity, plasma triglycerides and cholesterol as well as heart and left ventricular weight. The threshold to induce sustained VF was lower in rats exposed to high sucrose diet, while both melatonin and Omacor significantly increased it. There were no changes in Cx43mRNA among the groups. However, melatonin normalized the decreased Cx43 protein expression and its phosphorylation in HSD rats. Omacor did not affect total Cx43 levels, but enhanced functional phosphorylated forms of Cx43. Moreover both, melatonin and Omacor normalized diminished expression of PKCe and elevated expression of PKCd in rats exposed to high sucrose diet. Conclusions: Findings indicate that high sucrose diet of female Wistar rats results in downregulation of myocardial Cx43 and PKC signaling that may be related to the increased susceptibility of these rats to malignant arrhythmias. The adverse effects can be attenuated by the treatment with either melatonin or Omacor. This work was supported by VEGA 2/0046/12, 1/0032/14, 2/0167/15, 2/0021/15 and APVV 0241/11, 0348/12 grants.

Abstract oral session 5: Advances in atrial fibrillation ablation II

Monday, April 20, 2015, 10:30 AM–12:00 PM

5–1 Abstract 04–13

25 SITES OF ATRIAL FIBRILLATION ROTORS MAY OVERLAY GANGLIONATED PLEXI IN LEFT ATRIUM

Tina Baykaner¹, Junaid Zaman², Theodoros Zografos³, Ioannis Pantos³, David Krummen¹, Demosthenes Katritsis³, Sanjiv Narayan⁴

¹ University of California, San Diego, San Diego, CA, USA, ² Imperial College London, London, UK; ³ Athens Euroclinic, Athens, Greece; ⁴ Stanford University, Palo Alto, CA, USA

Introduction: The cardiac autonomic nervous system plays an important role in atrial fibrillation (AF). Recent advances in mapping human AF report localised sources (rotors) treatable by focal ablation. We hypothesised that such rotors may co-localise with ganglionated plexi (GP). Methods: We studied 70 consecutive patients with AF (61.1 ± 8.6 years, 73 % persistent) recorded with 64 pole contact catheters (Constellation, BSCI) and phase mapping of AF singularities (rotors) at EP study. Electroanatomic shells were analysed independently by four blinded observers for overlap with superior/inferior left GPs (SLGP, ILGP) or anterior/inferior right GPs (ARGP, IRGP). GP locations were referenced to a database. Results: AF sources arose in 68/70 (97 %) patients with a mean of 2.1 ± 1.0/each (left atria, LA 1.4 ± 0.8, right atria, RA 1.0 ± 0.7). Of all patients, 65 patients had LA sources. Of these, 55 patients (85 %) had at least 1 rotor that co-localised with a GP, either definitely (24 patients, 27 %) or possibly (31 patients, 48 %). Out of 96 LA rotors identified, only 15 were not related to any GP. The figure shows 3 targeted rotors overlapping GP, and 1 RA rotor with no GP overlap. There was a correlation between increasing number of LA rotors and the likelihood of a rotor coinciding with a GP site (p < 0.001). Conclusions: Fibrillatory rotors in human left atria commonly occur at sites of GPs, offering a possible physiological basis for source formation and targeted ablation. Future studies should define how patient-specific GP locations may sustain AF and the order of importance of these sites of structure/function co-localisation.

5–2 Abstract 28–16

26 FEASIBILITY OF A NON-INVASIVE ELECTROCARDIOGRAPHIC MAPPING SYSTEM AT LOCALISATION OF ECTOPY TO GUIDE ABLATION IN PATIENTS UNDERGOING REPEAT CATHETER ABLATION FOR ATRIAL FIBRILLATION

Norman Qureshi¹, Cheng Yao², Shahnaz Jamil-Copley¹, Michael Koa-Wing¹, Sajad Hayat¹, Fu Siong Ng¹, Afzal Sohaib¹, Elaine Lim¹, Ian Wright¹, Nick Linton¹, David Lefroy¹, Zachary Whinnett¹, Nicholas Peters¹, Prapa Kanagaratnam¹, Phang Boon Lim¹, D Wyn Davies¹

¹ Imperial College, London, UK; ² CardioInsight Technologies, Cleveland, OH, USA

Pulmonary vein isolation (PVI) is the cornerstone of atrial fibrillation (AF) ablation. Long-term outcomes with PVI are plagued with recurrences necessitating multiple procedures. The major causes of recurrence are PV re-connection and non-PV triggers. We used a non-invasive electrocardiographic mapping (ECM) system to localise PV and non-PV triggers, and guide ablation, in patients undergoing repeat AF ablations. Twelve patients undergoing repeat AF ablation for recurrent symptomatic paroxysmal atrial tachycardia (AT)/AF documented on ambulatory ECG monitoring underwent pre/peri-procedural mapping using a 252-electrode vest to locate the premature atrial complex (PAC) break-out sites. All PVs were re-isolated, and non-PV triggers mapped were targeted during the procedure. Twelve patients (54 ± 11 years, 50 % male, CHADSVASC 1 (0–3)) undergoing repeat AF ablation (mean no. of previous procedures 2.9 (1–4)) underwent pre and peri-procedural ECM. Eleven (92 %) patients had at least 1 PV reconnection (mean 2 (1–4)), and only one patient had maintained PV isolation in all four veins (8 %). Seven PV and eight non-PV foci were mapped with ECM. The PV foci originated from the RUPV (4), RIPV (2) (see Fig. 2) and L common PV (1). The non-PV foci originated from the superior vena cava (4) (see Fig. 1), left atrial septum (2), right atrial septum (1) and cristae terminal is (1). One patient did not have any PAC on the day of the procedure. Three patients had multiple foci, and the remaining (8/12) had a single focus (4 PV and 4 non-PVI foci). Five of 11 (45 %) had recurrence of symptoms with documented paroxysmal AF/AT at 6 months, but two of these were likely to represent un-ablated ATs seen during the procedure. One patient has yet to reach the 6-month follow-up. Conclusion: Non-invasive ECM can accurately identify sites of PV and non-PV triggers in patients undergoing repeat catheter ablation for AF. This can help devise an ablation strategy pre-procedurally.

5–3 Abstract 15–46

27 SIMILARITY OF SUBSTRATES IN PATIENTS WITH POST-ABLATION RECURRENT PAROXYSMAL ATRIAL FIBRILLATION VERSUS PERSISTENT ATRIAL FIBRILLATION: A 10-CENTER PROSPECTIVE STUDY

Junaid Zaman¹, Vijay Swarup², Robert Kowal³, James Daubert⁴, John Day⁵, John Hummel⁶, David Krummen⁷, Moussa Mansour⁸, Vivek Reddy⁹, Kevin Wheelan³, Sanjiv Narayan¹, John Miller¹⁰

¹ Stanford University, Stanford, CA, USA, ² Arizona Heart Rhythm Center, Phoenix,AZ, USA; ³ Baylor University Medical Center, Dallas, TX, USA, ⁴ Duke University Medical Center, Durham, NC, USA; ⁵ Intermountain Medical Center, Salt Lake City, UT, USA; ⁶ Ohio State University, Columbus, OH, USA; ⁷ University of California, San Diego, San Diego, CA, USA; ⁸ Massachusetts General Hospital, Boston, MA, USA; ⁹ Mount Sinai School of Medicine, New York, NY, USA; ¹⁰ Indiana University School of Medicine, Indianapolis, IN, USA

Introduction: The role of atrial fibrillation (AF) substrates is unclear in patients with paroxysmal AF (PAF) that recurs after pulmonary vein (PV) isolation. We hypothesised that AF-maintaining substrates in redo-PAF patients is closer to those with persistent AF than to initial PAF. Methods: In 134 patients (LA size 56.6 ± 8 mm, LVEF 55.6 ± 9 %), AF was recorded in both atria using 64 pole-baskets, and custom software was used to identify sources. Substrate characteristics were compared between patients at 1st ablation for PAF, redo-ablation for PAF and persistent AF. Results: AF sources occurred in 99 % of patients (133/134). Patients at first PAF ablation (n = 22), compared to persistent AF (n = 88), had fewer sources (2.3 ± 1.0 vs 2.8 ± 1.3, p = 0.08), nearer the PVs (24.0 vs 18.0 %, p = 0.18), and required less ablation time (13.2 ± 9.0 vs 18.6 ± 11.7 min, p < 0.03; figure). Conversely, compared to persistent AF patients, those for redoPAF (n = 24) had similar source numbers (3.0 ± 1.6 vs 2.8 ± 1.3, p = 0.44) proportions near the PVs (16.2 vs 18.3 %, p = 0.68), and ablation time (15.9 ± 12.2 vs 18.6 ± 11.7, p = 0.29). PAF patients at first ablation had lower LA diameters (p < 0.004), heart failure class (p = 0.05), and CHADS2 score (p = 0.07) than persistent AF patients. These differences did not exist in redoPAF patients. Conclusions: PAF patients with recurrent AF after PVI are closer to patients with persistent AF, in numbers and locations of substrates (rotors) and comorbid conditions, than to first-time PAF ablation patients. This implies common mechanisms of AF in diverse groups. Classifying substrate may help to define a more accurate patient classification in order to tailor ablation to individual physiology.

5–4 Abstract 15–37

28 FEASIBILITY, SAFETY AND COSTS OF DAY CASE AF ABLATION

Sarah Anderson¹, Conn Sugihara¹, Ragunath Shunmugam¹, Rick Veasy¹, Aerakondal Gopalamurugan¹, Steve Furniss¹, Neil Sulke¹

¹ Cardiology Research Department, Eastbourne Hospital, East Sussex Healthcare NHS Trust, UK, Eastbourne, UK

Background: In most institutions, patients undergoing AF ablation are routinely admitted for at least one night post-procedure. At our institution, if patients are clinically stable and accompanied, they are offered day case discharge. All patients are instructed to re-present directly to the cardiac care unit at any time if they have any concerns. Methods: The medical records for 150 consecutive AF ablations performed under sedation between October 2013 and July 2014 were examined. Demographics, procedural factors and complications were described. All re-attendances to secondary care within 30 days of the ablation were recorded regardless of the cause. Results: Thirty-one percent of AF ablations were performed as day case procedures. There were no complications. There were no significant differences in demographics, procedure times or early post procedural reattendance compared to overnight stay patients.

	Day case AF ablation	Overnight stay after ablation	Total	P value
N	46	104	150
Technology used, A multipolar cathether RF ablation, B point-to-point ablation, C Cryo ablation	A 86 %, B 7 %, C 7 %	A 88 %, B 9 %, C 3 %	A 87 %, B 8 %, C 5 %	NS
1. Paraxsysmol AF, 2. Persistant AF	1. 86 %, 2. 19 %	1. 80 %, 2. 18 %	1. 83 %, 2. 18 %	NS
Age in years (range)	66 (44 to 83)	66 (34 to 88)	66 (34 to 88)	NS
Female (%)	50	48	49	NS
Mean overall procedure duration (min)	100	102	102	NS
Median duration of hospital stay	9 h	27 h	26 h	<0.001
Any re-attendance within 30 days	5 (11 %)	15 (14 %)	20 (13 %)	NS
2014 NHS tariff cost of admission hospital bed	£225	£705

5-5 Abstract 15–41

29 SAFETY AND EFFICACY OF PULMONARY VEIN ISOLATION USING A CIRCULAR, OPEN IRRIGATED MAPPING AND ABLATION CATHETER: A MULTI CENTER REGISTRY

Ermenegildo de Ruvo¹, Massimo Grimaldi², Giovanni Rovaris³, Ezio Soldati⁴, Giuseppe Stabile⁵, Matteo Anselmino⁶, Francesco Solimene⁷, Assunta Iuliano⁵, Vincenzo Schillaci⁶, Luigi Sciarra¹, Maria Grazia Bongiorni⁴, Fiorenzo Gaita⁶, Leonardo Calò¹

¹ Policlinico Casilino ASL RM/B, Rome, Italy; ² Ospedale Miulli, Acquaviva delle Fonti, Italy; ³ Osedale San Gerardo, Monza, Italy; ⁴ Azienda Ospedaliero Universitaria Pisana, Pisa, Italy; ⁵ Clinica Mediterranea, Napoli, Italy; ⁶ Dipartimento Scineze Mediche, Università di Torino, Torino, Italy; ⁷ Clinica Montevergine, Mercogliano, Italy

Introduction. Pulmonary vein isolation (PVI) is the cornerstone of catheter ablation in patients with atrial fibrillation (AF). “Single shot” ablation devices have been recently engineered. We report on the acute safety and efficacy of a novel ablation catheter for PVI in patients with paroxysmal and persistent AF. Methods. One hundred-eighty consecutive patients (58 ± 10 years, 125 males, 31 % with structural heart disease) referred for paroxysmal (140 patients) or persistent (40 patients) AF underwent PVI by an open-irrigated mapping and radiofrequency (RF) decapolar ablation catheter (nMARQ, Biosense-Webster Inc., Diamond Bar, CA) in seven Italian centers. Ablation was guided by electroanatomic mapping allowing RF energy delivery in the antral region of pulmonary veins (PVs) from ten irrigated electrodes simultaneously. A maximum of 25 W were applied per vein. Results. Mean overall procedure time was 113 ± 53 min with a mean fluoroscopy time of 13.1 ± 8.4 min. The use of a pre-ablation PV imaging related to a significant reduction in fluoroscopy time (from 14.7 ± 9.7 to 8.7 ± 6.6, p < 0.001). Mean ablation time (RF time needed for PVI) was 12.5 ± 5.1 min; 98 % of the targeted veins were isolated with a mean of 23.4 ± 6.3 RF pulses per patient. In only four patients, a single point ablation strategy was required to achieve the PVI. No stroke/TIA, pericardial effusion, or cardiac tamponade were observed. Only one groin hematoma was reported. Conclusions. In this multicenter registry, irrigated multi-electrode RF ablation resulted widely feasible, achieving a high rate of isolated PVs. In addition, procedural and fluoroscopy times were comparable with other techniques and, importantly, related to low complication rates. Pre-ablation imaging allowed reduced fluoroscopy time.

5–6 Abstract 15–40

30 SINGLE-CENTRE EXPERIENCE AND OUTCOME OF PERSISTENT AF ABLATION USING THE NMARQ CATHETER: 2-YEAR FOLLOW-UP

Shunmugam Ragunath Shunmugam¹, Rick Veasey¹, Conn Sugihara¹, Sarah Anderson¹, Aerakondal Gopalamurugan¹, Furniss Steve¹, Sulke Neil¹

¹ East Sussex health care NHS trust, Eastbourne, UK

Introduction: The nMARQ ablation system allows for mapping and AF ablation via a continuously irrigated decapolar lasso-configuration catheter. nMARQ ablation was initially used in paroxysmal AF (PAF), but is increasingly being used in persistent AF (PersAF). We describe our experience of nMARQ ablation for PersAF, with 2-year follow-up data available. Methods: Fifty-seven consecutivenMARQablations for PersAF performed between September 2012 and March 2014 were analysed. Medical history, screening and procedure times, requirement and time duration to repeat ablation and ablation complications were collated. Repeat ablations for AF or atrial tachycardia (AT) were compared with 100 nMARQ and 100 PVAC ablations for PAF, at our institution. Results: The mean age of patients was 64.9 years, and 20 % were female. Mean AF duration prior to ablation was 39 months. Mean ejection fraction was 55 %, mean left atrial diameter 4.6 cm. Thirty-nine percent had hypertension. Mean CHA2DS2-Vasc score was 1.6. Mean procedure time was 94.5 min. All patients underwent pulmonary vein isolation, and 70 % received additional CAFE guided ablation: 50 % to the septum, 50 % to inferior LA and 30 % also had a cavotricuspid isthmus line. There were no procedural complications. Fourteen percent of patients required a repeat ablation for AF recurrence (8.8 %) or AT (5.2 %). The mean duration to repeat ablation from the first procedure was 547 days. Time to requirement of repeat ablation from first ablation did not show any significant difference between nMARQ ablations for Pers AF and nMARQ or PVAC ablations for PAF. Conclusions: Use of nMARQ catheters for Pers AF ablation is safe and has a similar time required to repeat ablations compared to PAF ablation with nMARQ and PVAC catheters. The nMARQ catheters and the system is flexible enough to allow non-pulmonary vein targets to be ablated and hence can be considered a potential first-line technology for Pers AF ablation.

Abstract oral session 6: Cardiac resynchronization therapy: techniques and outcome

Monday, April 20, 2015, 10:30 AM–12:00 PM

6–1 Abstract 24–20

31 A HIGHLY EFFECTIVE TECHNIQUE FOR TRANSSEPTAL ENDOCARDIAL LEFT VENTRICULAR LEAD PLACEMENT FOR DELIVERY OF CARDIAC RESYNCHRONISATION THERAPY

Giulia Domenichini¹, Ihab Diab², Niall Campbell¹, Mehul Dhinoja¹, Ross Hunter¹, Simon Sporton¹, Mark Earley¹, Richard Schilling¹

¹ Department of Cardiology, St Bartholomew’s Hospital, London, UK; ² The Bristol Heart Institute, University Hospital Bristol NHS Foundation Trust, Bristol, UK

Background: Endocardial transseptal left ventricular (LV) lead delivery is challenging due to the absence of dedicated equipment designed for this procedure. We describe a new technique for delivery of a transseptal LV lead. Methods: Patients (pts) with class 1 indication for CRT and a previous failed attempt at conventional LV lead placement via the coronary sinus were offered this procedure. All pts were anticoagulated with warfarin. The implantation technique is shown in the Figure. A left subclavian and right femoral venous access are initially obtained. a a gooseneck snare (a) is opened in the right atrium (RA) through which an Endry’s needle and Mullin’s sheath (b) are advanced into the RA. b A transseptal puncture is made and a wire is placed in the left upper pulmonary vein. c The snare is advanced into the left atrium (LA) and an Attain sheath is advanced over the snare. d The snare is removed leaving the Attain sheath in the LA. e An active fixation lead is advanced through the sheath into the LV and screwed into the lateral wall. The sheath is split and removed. f All three LV leads are seen: (c) a previous transvenous lead, (d) a surgical epicardial lead and (e) the new active fixation lead. Results: The procedure was performed successfully in all 12 patients attempted. The median procedure and fluoroscopy time were 148 min (IQR 113–176) and 16 min (IQR 10–19). Endocardial LV lead electrical parameters were satisfactory at implant and stable over time. The only complication was a pocket haematoma in a pt with a sub-pectoral generator. There was no need for repeat procedures after a median follow-up of 97 days (IQR 36–250). Conclusion: This approach provides a reliable and effective alternative technique for delivery of an endocardial LV lead inserted transseptally into the LV.

6–2 Abstract 24–14

32 COMPARATIVE EFFECTIVENESS OF LEFT VENTRICULAR VERSUS BIVENTRICULAR PACING FOR CARDIAC RESYNHRONIZATION THERAPY: A META-ANALYSIS OF RANDOMIZED CONTROLLED TRIALS

Daniele Muser¹, Pasquale Santangeli², Andrew Epstein², Mathew Hutchinson², Erica Zado², David Callans², Alessandro Proclemer¹, Francis Marchlinski²

¹ Azienda Ospedalieera Santa Maria della Misericordia, Udine, Italy; ² Hospital of the University of Pennsylvania, Philadelphia, PA, USA

Background: Cardiac resynchronization therapy (CRT) reduces symptoms and improves survival in patients with severe left ventricular (LV) dysfunction and prolonged QRS duration. The extent to which such benefit is due to biventricular (BV) versus LV pacing is unclear. This systematic review and meta-analysis of randomized trials compares BV versus LV-only pacing in patients undergoing CRT. Methods: we searched PubMed central, BioMed Central, Embase, Cardiosource, clinicaltrials.gov, and ISI web of Science for randomized controlled trials specifically designed to compare BV versus LV only pacing in patients undergoing CRT. Data regarding all-cause mortality or heart transplantation, hospitalization, LV ejection fraction (LEF), and exercise tolerance (i.e., 6-min walking test and MWT) were extracted. Odds ratios (OR) and weighted mean difference (WMD) with their 95 % confidence intervals (CI) were calculated and pooled using a random-effect model. Results: We identified eight trials that enrolled 786 patients (age 63.3 ± 2,9 years, 73 % males) with severe LV dysfunction (LVEF 23.4 ± 1,9 %, 57 % ischemic cardiomyopathy, average QRS duration 173 ± 18 ms). Three hundred forty-two (43 %) patients were randomized to LV-only pacing. The mean follow-up duration was 6.5 ± 4.1 month. On pooled analysis, no difference was found between LV-only and BV pacing for the endpoints of death or heart transplantation (OR 1.12, 95 % CI 0.53–2.39, P = 0.77) and hospitalization (OR 0.46, 95 % CI 0.09–2.26, P = 0.34). Compared to BV pacing, LV-only pacing provided similar improvements in LVEF (mean increase 5.3 1.1 % vs 6.4 2.9 %, respectively; WMD −0.98, 95 % CI −2.47 to 0.51, P = 0.19) and exercise tolerance at 6 MWT (mean increase 46.4 24.6 m vs 51.9 20.4 m, respectively; WMD −4.43, 95 % CI −15.46 to 6.59, P = 0.43). Conclusions: LV-only pacing provides similar benefits to BV pacing in terms of all-cause mortality, need for transplantation, hospitalization, improvement in LVEF, and exercise tolerance. In patients treated with CRT who are not pacemaker-dependent, LV-only pacing is an alternative to increase battery longevity.

6–3 Abstract 31–16

33 ATRIAL RESYNCHRONIZATION COMBINED WITH “BACKGROUND” ANTIARRHYTHMIC THERAPY IMPROVES SURVIVAL IN PATIENTS WITH ATRIAL FIBRILLATION AND HEART FAILURE WITH OR WITHOUT SYSTOLIC LEFT VENTRICULAR DYSFUNCTION

Sanjeev Saksena¹, Marwan Saad¹, April Slee¹, Hansini Laharawani¹, Rangadham Nagarakanti¹

¹ Electrophysiology Research Foundation, Warren, MI, USA

Background: Dual-site right atrial pacing (DAP) produces biatrial electrical resynchronization, improved left atrial filling and reverse remodeling. We examined the long-term (>5 year) outcomes of DAP added to “background” (AAD) and/or ablation (ABL) therapy (Rx) in atrial fibrillation (AF) patients (pts) with heart failure (HF). Methods: Seventy-one pts with AF and HF refractory to AADs and/or ABL (n = 27) were implanted with DAP systems. HF subgroups were stratified by LV ejection fraction (LVEF) >45 % (HF preserved {p} EF) or <45 %(HF reduced {r}EF). Sinus rhythm maintenance (rhythm control) and long-term survival were evaluated. Results: HFpEF (n = 36) and HFrEF (n = 35) pts, mean age 67 ± 10 years, 69 % male, mean LV ejection fraction 43 + 14 %, mean NYHA class 2.5 were followed for 5.4 years (median, IQR 2.9–11.0). HFpEF pts were comparable for age, gender, AF class, prior AADs and NYHA HF class to HFrEF pts but had higher LVEF (53 + 5 vs. 31 + 10 % p < .001). Long-term follow-up was comparable (HFpEF median = 7.2 years, HFrEF = 5.1 years, p = 0.7) After DAP, rhythm control at last follow-up was comparable in HFpEF (89 %) and HFreF (85 %, p = ns) pts and in paroxysmal AF (90 %) and persistent AF (83 %, p = ns) pts. Fifty-seven percent of pts had >1 AF recurrence but 87 % of these pts remained in rhythm control. Total survival was 72 % at 5 years. Survival in pts with HFpEF was superior to HFrEF at 5 and 10 year (Figure). Conclusions: 1. AF pts with HFpEF and HFrEF achieve a comparably high degree of rhythm control with DAP and is maintained in a majority of AF pts with HF at 5 years. 2. Survival of HFpEF pts after DAP was superior to HFrEF and both were superior to historical data for AF with HF. 3. DAP may offer additional rhythm control and survival benefits for AF pts with HF due to electrical and mechanical resynchronization

6–4 Abstract 31–10

34 RATE DEPENDENT LEFT ATRIAL PRESSURE CHANGE IN PATIENTS WITH IMPAIRED LEFT VENTRICULAR DIASTOLIC FUNCTION: PACING VS. ISOPROTERENOL

Tae-Hoon Kim¹, Junbeom Park¹, Jin-Kyu Park¹, Jae-Sun Uhm¹, Boyoung Joung¹, Moon-Hyoung Lee¹, Hui-Nam Pak¹

¹ Yonsei University Health System, Seoul, Republic of Korea

Background: Although we previously reported that peak left atrial (LA) pressure during sinus rhythm (LAPpeak) is associated with the degree of LA remodeling and left ventricular (LV) diastolic function estimated by E/Em among the patients with atrial fibrillation (AF), hemodynamic linkage between LAPpeak and LV diastolic function has not yet been clearly explored. We hypothesized that isoproterenol (Iso) stress results in different LAPpeak responses depending on the existence of LV diastolic dysfunction. Methods: We measured LAPpeak in 175 patients (67.4 % male, 59.1 ± 10.5 years old, 69.7 % paroxysmal AF) who underwent radiofrequency catheter ablation for AF at the beginning of the procedures. LAPpeak was measured in sinus rhythm with right atrial pacing and Iso infusion (5 μg/min) at the heart rates (HR) of 90, 100, 110, and 120 bpm, respectively. We compared dynamic changes of LAPpeak between the patients with LVDD (E/Em > 15) (n = 26) and those without (control group, E/Em≤15) (n = 149). Results: 1. In contrast, LAPpeak was increased as paced heart rate (HR) increased generally (p < 0.001); it was gradually reduced as Iso induced HR increased (p = 0.014). 2. As increase of paced HR, LAPpeak was increased in both the control group (E/Em£15) (p < 0.001) and the LVDD group (E/Em > 15, p = 0.034). 3. With Iso stress HR response, LAPpeak was reduced in the control group (p = 0.006). However, LAPpeak response to Iso stress HR change was blunted in the LVDD group (p = 0.745). Conclusions: Responses of LAPpeak to HR increase have opposite tendency between paced tachycardia and Iso stress in total study population. However, LAPpeak change response to Iso stress is impaired in patients with LVDD, suggesting Iso-augmented LV diastolic function contributes to the reduction of LAPpeak.

6–5 Abstract 24–19

35 LONG-TERM FOLLOW-UP AFTER LEFT VENTRICULAR ENDOCARDIAL RESYNCHRONIZATION THERAPY: MORTALITY AND THROMBOEMBOLIC COMPLICATION

Zsuzsanna Kis¹, Imre Kassai¹, Attila Mihalcz¹, Attila Kardos¹, Csaba Foldesi¹, Andrea Arany², Gabriella Gyori², Tamas Szili-Torok³

¹ Gottsegen Gyorgy National Cardiology Institute, Budapest, Hungary; ² United St. Istvan and Laszlo Hospital, Budapest, Hungary; ³ Erasmus University, Rotterdam, Netherlands

Introduction: Cardiac resynchronization therapy (CRT) is an established therapeutic option in selected end-stage heart failure patients (pts). Despite the technological improvements in considerable amount of pts, the traditional transvenous left ventricle (LV) pacing lead implantation fails. The transapical LV lead implantation is a minimally invasive, surgical, endocardiac implanting technique. The long-term outcome of endocardial LV lead placement is unknown. Hypothesis: The aim of this prospective study was to determine the long-term mortality and cerebrovascular thromboembolic complications of patients who underwent transapical endocardial LV lead placement. Methods: Twenty-three CRT candidate pts (18 men (78 %); mean age 61.2 ± 10.5 years) not responding to traditional CRT or with a failed coronary sinus approach underwent transapical LV lead placement between 2007 and 2013. In all cases, the LV electrode was fixed into the basal-lateral segment of the LV. After the operation, the target INR level was aimed to be between 2.5 and 3.5. We assessed the long-term mortality rate and performed cerebrovascular CT scan to determine any possible thromboembolic event in relation to LV lead implantation. Results: Eleven out of 23 (47.8 %) patients were alive after a follow-up of 40 ± 24.5 months. One out of 11 alive patients was lost to follow-up. In two patients LV lead repositioning was performed. Native cerebral CT scan examination was performed in 7 out of 10 followed-up pts. Major acute ischaemic stroke occurred in one case (14.2 %) after transvenous implant of LV lead following transapical LV lead fracture. Due to the early postoperative period and oral anticoagulation therapy, thrombolytic therapy was contraindicated. In another case, transapical LV lead repositioning was indicated due to LV lead capture problem; 1 month later, left ventricle assist device was implanted. Conclusions: End-stage heart failure patients who underwent transapical LV lead implantation have a long-term mortality rate of approximately 50 %. Major ischaemic cerebrovascular event after transapical LV lead implantation is expected in limited cases.

6–6 Abstract 24–13

36 NON-ISCHEMIC CARDIOMYOPATHY AND LOW BURDEN OF SCAR AS REVEALED BY AN ECG-SCORE: NO NEED FOR A DEFIBRILLATOR IN SPECIAL PATIENTS AFTER CARDIAC RESYNCHRONISATION?

Martin Grett¹, Hans-Joachim Trappe¹

¹ Department of Cardiology and Angiology, University of Bochum, Bochum, Germany

Purpose: A definition of patients (pts) at very low risk for sustained ventricular tachycardia or ventricular fibrillation could lead to a more widespread use of CRT-pacemakers instead of defibrillators. A high burden of scar as a substrate of ventricular tachyarrhythmia can be ruled out by the modified Selvester-ECG-score (MSES), which correlates with the scar burden. Every 1 point raise counts for 3 % additional scar of the left ventricle (LV). In a retrospective analysis of SCD-HeFT it has shown a value in describing pts at high vs low risk for ICD-therapy. Its value in pts with indication for CRT was investigated by our department. Methods: We studied 74 pts who underwent CRT-D implantation and had complete follow-up of device interrogations for 3 years at our department. Pts with secondary prophylactic indication for ICD or upgrade from existing devices were not studied. Following characteristics among others were investigated: modified Selvester-ECG-score, LVEF and occurrence of adequate ICD-therapy. Results: Median LVEF was 20 % (range 10.0–29.0 %); median ECG-score was 4 (0–12). Eighty-five percent were male; mean age was 65,7 years. Aetiology of cardiomyopathy was ischemic (ICM) in 33 pts, non-ischemic (NICM) in 41. About one third of the pts (25/74) suffered adequate ICD-therapy in the 3-year period. NICM pts with a MSES of 3 points or less had no need for adequate ICD-therapies. These findings are shown in the table:

	ICM orNICM and MSES ≥ 4	NICM and MSES ≤ 3	p value
n	55	19
Age (mean)	66.7	62.7	0.052
Male (%)	89	74	0.106
LVEF % (mean)	19.8	21.8	0.144
ICD therapy	45 % (25/55)	0 % (0/19)
Relative risk for ICD therapy (95 % confidence interval)	18.21 (1.16–285.47)		0.038

Conclusion: Applying the modified Selvester-ECG-score to pts with non-ischemic cardiomyopathy and indication for CRT is a promising way to identify pts at very low risk for ICD-therapy. Management of pts with indication for CRT could be improved by use of this parameter, particularly with regard to the question if a CRT-Pacemaker is an alternative in more pts.

Abstract oral session 7: Mapping and ablation of ventricular arrhythmias

Monday, April 20, 2015, 10:30 AM–12:00 PM

7–1 Abstract 17–18

37 INTERMEDIATE TO LONG-TERM FOLLOW-UP OF IDIOPATHIC VENTRICULAR FIBRILLATION ABLATION

Cheryl Teres¹, Mehdi Namdar¹, Pascale Gentil-Baron¹, Henri Sunthorn¹, Haran Burri¹, Dipen Shah¹

¹ Hôpitaux Universitaires de Genève, Service de Cardiologie, Geneva, Switzerland, Geneva, Switzerland

Introduction: Catheter ablation of idiopathic ventricular fibrillation (VF) targeting ventricular premature beats (VPBs) originating from the ordinary myocardial muscle or within the Purkinje system has been shown to be very effective for the prevention of VF recurrences. Methods: Patients were referred for ablation of idiopathic VF triggered by short coupled VPBs after exclusion of a macroscopic arrhythmogenic substrate by extensive diagnostic workup including physical exam, blood tests, Holter monitoring, cardiac ultrasound and coronary angiography. They all had experienced cardiopulmonary resuscitation due to an episode of idiopathic VF and multiple VF episodes terminated by their ICD before radiofrequency (RF) ablation. RF ablation was guided by activation and pace mapping and aimed to abolish all clinical VPBs. Results: Three male patients (29, 55 and 58 years) underwent the ablation procedure. All three patients had experienced multiple appropriate ICD shocks for VF. VPBs showed LBBB morphology in all of them and had an ectopic QRS duration of 138, 168 and 158 ms and a coupling interval initiating VF of 384, 291 and 378 ms, respectively. Triggering VPBs originated from the RV apex, the anterior wall of the RVOT and the RV anterior muscular wall, respectively. In two patients, RF delivery triggered polymorphic non-sustained VT even at sites without Purkinje potentials and subsequently eliminated ectopy and Purkinje potentials at sites where best pace map was achieved. Suppression of reproducibly induced mechanical and RF provoked polymorphic VT and VF from a localized site in the RV anterior wall (with best pace map) was observed in one patient, suggesting combined suppression of trigger and local substrate. Ablation dramatically reduced the percentage of VPBs in two patients as confirmed by Holter ECG monitoring at maximal follow-up (1 and 10 VPBs), while one patient showed a recurrence of clinical VPBs. However, none of them experienced VF recurrence during a follow-up time of 5 years, 8 months and 10 years, respectively, as confirmed by interrogation of the ICD. Conclusion: Ablation of short coupled VPBs triggers shows a high efficacy in preventing VF recurrence in an intermediate and long-term follow-up in patients with idiopathic VF.

7–2 Abstract 17–10

38 ACUTE HEMODYNAMIC DECOMPENSATION DURING CATHETER ABLATION OF SCAR-RELATED VT: INCIDENCE, PREDICTORS AND IMPACT ON MORTALITY

Daniele Muser¹, Pasquale Santangeli², Silvia Magnani³, Erica Zado², Mathew Hutchinson², Gregory Supple², David Frankel², Fermin Garcia², Rupa Bala², Michael Riley², Eduardo Rame², Sanjay Dixit², Alessandro Proclemer¹, Francis Marchlinski², David Callans²

¹ Azienda Ospedaliera Santa Maria della Misericordia di Udine, Udine, Italy; ² Hospital of the University of Pennsylvania, Philadelphia, PA, USA; ³ Azienda Ospedaliera di Trieste, Trieste, Italy

Introduction: The occurrence of periprocedural acute hemodynamic decompensation (AHD) in patients (pts) undergoing catheter ablation (CA) of scar-related VT has not been previously investigated. Methods: Using logistic regression analysis, we identified predictors of AHD in 148 consecutive pts undergoing CA of scar-related VT. Periprocedural AHD was defined as persistent hypotension (systolic blood pressure <80–90 mmHg) despite vasopressors and requiring mechanical support and/or procedure discontinuation. A risk score was created from the rounded univariate odds ratios (OR). Results: Periprocedural AHD occurred in 19 (13 %) pts and was predicted by six factors: ischemic cardiomyopathy (OR = 6.12 [1.36–27.60], P = 0.018), EF < 25 % (OR = 2.97 [1.10 7.98], P = 0.031), NYHA class III or IV (OR = 6.84 [2.39–19.53], P < 0.001), COPD (OR = 3.84 [1.33–11.12], P = 0.013), VT storm (OR = 5.09 [1.41–18.32], P = 0.013), and general anesthesia (OR = 7.23 [2.43–21.53], P < 0.001). When applying the risk score derived from the ORs of the predictors (Figure), the risk of AHD was 2, 5, and 44 %, respectively, for increasing risk score tertile. At 20 ± 8 months follow-up, the mortality rate in the AHD group was 58 vs. 14 % in the rest of the population (P < 0.001). AHD was associated with increased risk of 6-month (OR = 6.36, P = 0.008) and 1-year (OR = 5.05, P = 0.008) mortality, independently of the risk score. Conclusions: Periprocedural acute hemodynamic decompensation occurs in 13 % of patients undergoing catheter ablation of scar-related VT and is associated with increased risk of mortality. A risk score comprising six factors can be used to identify these patients.

7–3 Abstract 28–14

39 FEASIBILITY OF USING RIPPLE MAPPING TO IDENTIFY AND ABLATE CONDUCTION CHANNELS WITHIN THE VENTRICULAR SCAR

Vishal Luther¹, Shahnaz Jamil-Copley¹, Nicholas Linton¹, Michael Koa-Wing¹, Sajad Hayat¹, Pasquale Vergara², Fu-Siong Ng¹, Zachary Whinnett¹, Phang Boon Lim¹, David Lefroy¹, David Wyn Davies¹, Nicholas Peters¹, Paolo Della Bella², Prapa Kanagaratnam¹

¹ Imperial College Healthcare NHS Trust, London, UK; ² San Raffaele Hospital, Milan, Italy

Introduction: Ripple mapping (RM) displays each component of the electrogram at its corresponding 3D coordinate overlying a voltage map as a dynamic bar that changes in height according to the electrogram voltage-time relationship. We tested the feasibility of using CARTO Ripple Map to identify conduction channels (RM-CC) in a prospective series of ischemic ventricular tachycardia (VT) ablations for recurrent implantable-defibrillator (ICD) therapies Methods: Bipolar LV endocardial voltage maps were collected with CARTO3 v4 in sinus or paced rhythms by robotic navigation (Sensei System™) with Smart Touch-irrigated catheter. Ripple maps were reviewed for RM-CCs with 4/5 criteria used to define RM-CCs (see figure). VT induction was performed and ablation was delivered in stable VT and at all RM-CC sites. Results: Seven patients (100 % male, age 74 ± 9, ejection fraction 31 ± 7 %) with a median of 7 ATPs and 2 shocks in the 30-day pre-ablation period were recruited. Dense LV maps were collected (total area 243 ± 54 cm², scar percentage 44 ± 22 %, 607 ± 296 scar points). Six maps were collected with ConfiDense-automated point collection. RM-CCs (median 3, range (1–5)) were seen within each map (35 ± 15-mm length), 11 of which exited within scar-border zone. Six of 20 RM-CCs co-located to voltage channels (mean 0.35–0.45 mV). Clinical VT (450 ± 83 ms) was induced in 6/7 cases and 2 were ablated in VT by conventional criteria, and sites of termination were within an RMCC. All RM-CCs were ablated (median 8 lesions per RMCC). Clinical VT was non-inducible in all cases and procedure duration was 295 ± 74 min. There were no peri-procedural complications. There were no episodes of sustained VT recurrence or ICD therapies at 30 days. Conclusion: In this small series of prospective VT ablations, identification of CCs using ripple mapping was feasible, ablation of which lead to elimination of the clinical VT.

7–4 Abstract 18–19

40 NON-RANDOMISED COMPARISON OF ACUTE AND LONG TERM OUTCOMES OF ROBOTIC VERSUS MANUAL VENTRICULAR TACHYCARDIA ABLATION.

Vishal Luther¹, Shahnaz Jamil-Copley¹, Michael Koa-Wing¹, Matthew ShunShin¹, Ian Wright¹, Sajad Hayat¹, Nicholas Linton¹, Phang Boon Lim¹, Zachary Whinnett¹, David Lefroy¹, Nicholas Peters¹, David Wyn Davies¹, Prapa Kanagaratnam¹

¹ Imperial College Healthcare NHS Trust, London, UK

INTRODUCTION: Robotically guided radiofrequency (RF) ablation offers greater catheter stability that may improve lesion depth. There is very limited data on the clinical effectiveness of robotically guided VT ablation. We performed a non-randomised comparison of patients undergoing ventricular tachycardia (VT) ablation either manually or robotically using the Hansen Sensei system for recurrent implantable defibrillator (ICD) therapy. METHODS: Patients with infarct-related scar underwent VT ablation using the Hansen system to assess feasibility compared with patients undergoing manual VT ablation during a similar time period. All cases underwent a transeptal endocardial approach, using CARTO™ and irrigated catheter ablation guided by activation and entrainment manoeuvres if VT was sustained and tolerated, or substrate modification. Power delivery during robotic ablation was restricted to 30 W at 60 s. VT inducibility was checked at the end of the procedure. Pre-ablation ICD therapy burdens over 6 months were compared with post-ablation therapy averaged to a 6-month period. RESULTS: Twelve consecutive patients who underwent robotic VT ablation were compared to 12 consecutive patients undergoing a manual ablation. Patient demographics and comorbidities were similar in the two groups. A significantly higher proportion of robotic cases were urgent (9/12 (75 %)) vs. manual (4/12 (33 %)) (p = 0.01). Post-ablation VT stimulation did not induce clinical VT in 11/12 (92 %) in each group. There were no peri-procedural complications related to ablation delivery. Patients were followed up for approximately 2 years. Averaged over 6 months, robotic ICD therapy burdens fell from 32 (5–400) events to 2.5 (0–11) (p = 0.015). This represented a 95 % therapy burden reduction. Therapy burden fell from 14 (10–25) to 1 (0–5) (p = 0.023) in the manual group. There was no difference in long-term outcome (p = 0.60) and mortality (4/12 (33 %) p = 1.0). CONCLUSION: Robotically guided VT ablation is both feasible and safe when compared to manual ablation with good acute and long term outcomes.

Clinical characteristics	Robotic	Manual	p value
N	12	12	1a
Age/year (mean ± SD)	70.8 ± 5.5	73.8 ± 6.7	0.24c
LVEF 2D echo (mean ± SD)	28.1 ± 13.7 %	31.2 ± 10.7 %	0.53c
Total ATPs 6 months pre abl. (median (IQR))	19 (4–396)	11 (8–22)	0.56c
Total shocks 6 months preabl. (median (IQR))	1.5 (1–4)	1 (0–3)	0.73c
Previous manual ablation	4/12 (33 %)	1/12 (8 %)	0.32a
No. of VTs induced (mean ± SD)	2.4 ± 1.9	1.7 ± 1.0	0.31c
Scar location
Anterior	4	3	1a
Inferior	4	7	0.41a
Apical	4	2	0.65a
Maximum power/W (mean ± SD)	29.6 ± 2.7	44.6 ± 10.0	<0.001c
Overall procedure duration/min (mean ± SD)	312 ± 91	218 ± 93	0.02c
Post proc VT non-ind	6/12 (50 %)	8/12 (67 %)	0.68a
Post proc non-clinical VT ind	5/12 (42 %)	3/12 (25 %)	0.67a
Post proc clinical VT ind	1/12 (8 %)	1/12 (8 %)	1a
Follow up (months) (mean ± SD) (median (IQR))	24.1 ± 19.1, 27 (5–40)	21.1 ± 14.6, 22 (9–32)	0.77b
Total ATP’s post abl. (median (IQR))	3.5 (1–10)	0.5 (0–11)	0.38b
Total Shocks post abl. (median (IQR))	0.6 (0–1)	0 (0–2)	0.52b
Total ICD therapies post abl (median (IQR))	3.5 (1–11)	1 (0–14)	0.38b
6-month averaged ICD therapies (median (IQR))	Pre 32 (5–400)	Pre 14 (10–25)	0.49b
	Post 2.5 (0–11)	Post 1 (0–5)	0.60b
	p = 0.015d	p = 0.023d
Further ablation procedure	3/12 (21 %)	4/12 (29 %)	1a

abl ablation, Atp Anti-tachycardia pacing, ICD implantable cardioverter defibrillator, ind inducible, LVEF left ventricular ejection fraction, proc procedural

^aFisher’s exact test

^bMann–Whitney U test

^cStudent’s t test

^dWilcoxon signed rank test

7–5 Abstract 17–14

41 CLINICAL EXPERIENCE USING A NEW FLUOROSCOPY-INTEGRATED CATHETER TRACKING SYSTEM (MEDIGUIDE) FOR ABLATION OF VENTRICULAR TACHYCARDIA—A CASE-MATCHED COMPARISON

Michael Derndorfer¹, Elisabeth Sigmund¹, Georgios Kollias¹, Siegmund Winter¹, Helmut Pürerfellner¹, Josef Aichinger¹, Martin Martinek¹

¹ Elisabethinen University Teaching Hospital of the Universities Innsbruck, Vienna and Graz; Linz, Austria, Linz, Austria

Mediguide (MG) represents a new catheter tracking system integrated into the C-arm of a standard fluoro unit. After recording of short fluoro loops (RAO, LAO position), the tip of MG-catheters is precisely visualized onto these, allowing non-fluoroscopic tracking within EnSite NavX. Objective: We assessed system feasibility, safety and intraprocedural parameters for radiofrequency-ablation of ventricular tachycardias (VT) in patients with structural heart disease (SHD) or idiopathic VT. Methods: Sixty-three consecutive VT-patients (21 MG, 42 “conventional” using a standard 3D system) were retrospectively compared in a 2:1, closely case-matched comparison. Thirteen patients (61.9 %) in the MG-group and 23 patients (54.7 %) in the conventional group showed SHD. Ten (MG, 47.6 %) vs. 25 (conventional, 59.5 %) patients had a history of recurrent ICD shocks. Procedural parameters were compared between both groups. The end point of non-inducibility was used for all patients. Results: Mean fluoroscopy time (p = 0.0001) and radiation dose (p = 0.008) were significantly reduced by the use of MG. Of fluoroscopy dose in the MG group, 58.3 % was acquired in “non-MG-dependent” situations (positioning of conventional reference catheters, introducing sheaths, performing transseptal punctures) showing a great potential in further improvement. No major complications occurred in both groups. Conclusions: The use of the novel MG catheter positioning system is feasible and safe in VT ablation, significantly reducing fluoroscopy time and radiation dose compared to standard 3D systems.

7–6 Abstract 18–35

42 PROGNOSTIC VALUE OF ENDOCARDIAL MAPPING RESULTS IN PEDIATRIC PATIENTS WITH IDIOPATHIC VENTRICULAR ARRHYTHMIAS

Sergey Termosesov¹, Igor Khamnagadaev¹, Maria Shkolnikova¹, Ilya Ilich¹, Yanina Volkova¹, Rustem Garipov¹

¹ Research and Clinical Institute for Pediatrics at the Pirogov Russian National Research Medical University, Moscow, Russia

Background: Idiopathic ventricular arrhythmias (VAs) in children can cause significant morbidity and, although rare, mortality. Mapping of VA substrate should be precise because of safety reasons in pediatrics patients. The purpose of this study is to evaluate the prognostic value of endocardial activation and pace mapping of VA substrate in pediatric patients. Methods: In 2003–2014, 505 children aged 1 to 17 received invasive treatment of VA in one hospital. Three hundred thirty-seven of them (144 females) have been included into the study. ECG, 24-h Holter monitoring and echocardiography were performed. Activation and pace mapping results have been included into logistic regression model. Regression coefficients, odds ratio and probability of effective ablation depending from results of endocardial mapping were calculated. Results: The probability of successful ablation (P) was divided into three grades: “low” (P < 0.75), “medium” (0.75 < P < 0.9) and “high” (P > 0.9). During evaluation of presystolic activation time (T), low P was calculated for T < 29 ms, medium P was calculated if 29 ms < T≥73 ms and high P was determined for T > 73 ms. Early presystolic spike was recorded in most cases in this group. In pace mapping study, results were divided in two groups: “similar” and “identical”. Only medium P was found in both cases. But, P in identical pace mapping group was found in 2.6 times higher than in similar. Conclusion: Evaluation of presystolic activity allows predicting the successful ablation of VA. The probability of successful ablation of VA can be divided in low, medium and high grades during endocardial mapping. Earliest presystolic activation greater than 72 ms is associated with highest success rate. Pace mapping may be useful if results of activation mapping are not acceptable.

Abstract oral session 8: Clinical and genetic aspects of ARVD/C

Monday, April 20, 2015, 10:30 AM–12:00 PM

8–1 Abstract 07–12

43 CLINICAL CHARACTERISTICS AND OUTCOME OF PEDIATRIC-ONSET ARRHYTHMOGENIC RIGHT VENTRICULAR DYSPLASIA/CARDIOMYOPATHY

Anneline S. te Riele¹, Cynthia A. James¹, Abhishek C. Sawant¹, Brittney Murray¹, Crystal Tichnell¹, Ryan Tedford¹, Jane Crosson¹, Daniel P. Judge¹, Hugh Calkins¹, Harikrishna Tandri¹

¹ Johns Hopkins University School of Medicine, Baltimore, MD, USA

Background: Arrhythmogenic right ventricular dysplasia/cardiomyopathy (ARVD/C) is an inherited cardiomyopathy with an increased risk of sudden death. While affected patients typically present in the third decade of life, ARVD/C is not uncommon among adolescents. However, the clinical characteristics of pediatric-onset ARVD/C are largely unknown. Objective: (1) to describe the presenting symptoms, clinical attributes, and outcome of pediatric-onset ARVD/C and (2) to compare these to adult-onset ARVD/C. Methods: We obtained detailed phenotypic, genetic, and outcome data of 347 definite ARVD/C patients. Patients were grouped into pediatric (diagnosis <18 years) and adult (diagnosis ≥18 years) ARVD/C. Details regarding clinical presentation and outcomes (sustained ventricular tachycardia [VT], cardiac transplantation, and death) were ascertained. Results: Among 347 ARVD/C patients, 52 (15 %) were diagnosed prior to the age of 18 years. Pediatric cases were 28 (54 %) males, with a mean age of 15.4 ± 1.8 years at time of diagnosis. Compared to adult cases, pediatric cases were more likely to present with sudden cardiac death or resuscitated sudden cardiac arrest (25 vs 11 %, p = 0.004). Conversely, adult cases more often presented with sustained monomorphic VT (38 vs 21 %, p = 0.022). Compared to adult cases, pediatric cases were disproportionately mutation carriers (77 vs 59 %, p = 0.026), but not more likely to carry multiple mutations (3 vs 4 %, p = 0.729) or to be probands (28 vs 28 %, p = 0.968). There were no other differences in demographic characteristics or in any domain of the TFC. During 8.1 ± 7.3 years follow-up, there were no differences in survival free from sustained VT (p = 0.657), cardiac transplantation (p = 0.624), or death (p = 0.293) between pediatric and adult cases. Conclusion: Pediatric ARVD/C patients are more likely to present with sudden cardiac arrest, whereas adult cases more often present with sustained monomorphic VT. Pediatric ARVD/C cases are disproportionately mutation carriers. All other clinical characteristics and outcomes are similar between pediatric and adult ARVD/C patients.

8–2 Abstract 07–19

44 SARCOMERIC MUTATIONS ARE ASSOCIATED WITH ARRHYTHMOGENIC RIGHT VENTRICULAR DYSPLASIA/CARDIOMYOPATHY (ARVD/C)

Dennis Dooijes, University Medical Center Utrecht, Utrecht, The Netherlands; Judith A Groeneweg, University Medical Center Utrecht and Interuniversity Cardiology Institute of the Netherlands, Utrecht, The Netherlands; Brittney Murray, Johns Hopkins University School of Medicine, Baltimore, MD, USA; Daniel P Judge, Johns Hopkins University School of Medicine, Baltimore, MD, USA; Crystal Tichnell, Johns Hopkins University School of Medicine, Baltimore, MD, USA; Jan DH Jongbloed, University Medical Center Groningen, Groningen, The Netherlands; J Peter van Tintelen, University Medical Center Groningen, Groningen, The Netherlands; Hugh Calkins, Johns Hopkins University School of Medicine, Baltimore, MD, USA; Richard N Hauer, University Medical Center Utrecht and Interuniversity Cardiology Institute of the Netherlands, Utrecht, The Netherlands; Cynthia A James, Johns Hopkins University School of Medicine, Baltimore, MD, USA

Introduction: Arrhythmogenic right ventricular dysplasia/cardiomyopathy (ARVD/C) is in over 60 % of cases related to pathogenic mutations in desmosomal genes PKP2, DSG2, DSC2, DSP and JUP and non-desmosomal genes TMEM43 and PLN. However, in a significant proportion of proven ARVD/C patients, no pathogenic mutation can be identified in any of the known ARVD/C genes.

Aim: The study aims to investigate the contribution of sarcomeric gene mutations to the aetiology of ARVD/C.

Methods: Fifty-one proven ARVD/C patients (fulfilment of 2010 Task Force Criteria), from 43 families, were selected from the joint transatlantic JHU/ICIN ARVD/C registry in whom previous genetic analyses failed to identify a pathogenic mutation in any of the PKP2, DSC2, DSG2, DSP, JUP and TMEM43 genes. DNA from these 51 patients was analysed for mutations in the sarcomeric ACTC1, MYBPC3, MYH7, MYL2, MYL3, TNNC1, TNNI3, TNNT2 and TPM1 genes. DNA variants were assessed for potential pathogenic character using available in silico analysis tools and international databases.

Results: In 20 % of patients (10/51), a likely pathogenic mutation was identified in the sarcomeric MYBPC3, MYH7 or MYL3 gene, not previously associated with ARVD/C. Of these patients, eight had a mutation in the MYBPC3 gene, one had a mutation within the MYH7 gene and one had a mutation in the MYL3 gene. Following the identification of sarcomeric gene mutations in ARVD/C patients, a second group of 15 ARVD/C patients were genetically analysed using a panel also including sarcomeric genes. In this group, three additional patients were identified with an MYH7 mutation (20 %).

Conclusion: Analysis of sarcomeric ACTC1, MYBPC3, MYH7, MYL2, MYL3, TNNC1, TNNI3, TNNT2 and TPM1 genes in a group of proven ARVD/C patients without pathogenic mutation in the known ARVD/C genes resulted in the identification of likely pathogenic mutations in the sarcomeric MYBPC3, MYH7 and MYL3 genes. These data for the first time show an association between mutations in the sarcomere and the ARVD/C phenotype.

Currently, patient numbers are too small to investigate genotype-phenotype relations. However, the present results warrant genetic testing of sarcomeric genes in ARVD/C patients without underlying genetic defect in any of the known ARVD/C genes.

8–3 Abstract 07–18

45 PREGNANCY IN ARRHYTHMOGENIC RIGHT VENTRICULAR DYSPLASIA/CARDIOMYOPATHY IS ASSOCIATED WITH A LARGELY UNEVENTFUL COURSE DELIVERY

Anke R. Hodes¹, Crystal Tichnell², Anneline S.J.M. te Riele³, Brittney Murray², Judith A. Groeneweg⁴, Abhishek C. Sawant², Stuart D. Russell², Maarten P. van den Berg¹, Arthur A. Wilde⁵, Harikrishna Tandri², Daniel P. Judge², Richard N.W. Hauer⁴, Hugh Calkins², J. Peter van Tintelen⁵, Cynthia A. James²

¹ University Medical Center Groningen, Groningen, Netherlands, ² Johns Hopkins University, Baltimore, MD, USA; ³ University Medical Center Utrecht, Utrecht, Netherlands; ⁴ Interuniversity Cardiology Institute of the Netherlands, Utrecht, Netherlands; ⁵ Academic Medical Center, Amsterdam, Netherlands

Background: Arrhythmogenic right ventricular dysplasia/cardiomyopathy (ARVD/C) is an autosomal-dominant inherited cardiomyopathy clinically characterized by a high incidence of ventricular arrhythmias and an increased risk of sudden cardiac death. Earlier detection and successful treatment of ARVD/C has increased the number of patients considering pregnancy. Present literature regarding pregnancy and ARVD/C only includes one small (n = 6) case series and five isolated case reports. We aim to provide additional clinical insight in pregnancy outcome for both mother and child. Methods: In a combined Johns Hopkins/Interuniversity Cardiology Institute of the Netherlands ARVD/C registry, we identified 26 women (5 Dutch; 13 probands, 13 relatives) who met ARVD/C 2010 Task Force Criteria during 39 singleton pregnancies >13 weeks (1–4 per woman). Cardiac and obstetric outcomes were ascertained in all. Results: Pregnancy began at a mean age of 31.2 ± 3.5 years. ARVD/C was diagnosed prior to most pregnancies (n = 29; 74 %), whereas in 7 (18 %), ARVD/C was present but not yet clinically recognized and 3 pregnancies (8 %) were ongoing at diagnosis. Treatment in pregnancies included beta blockers (n = 16), sotalol (n = 4), flecainide (n = 1), digoxine (n = 1), diuretics (n = 3) and ICDs (n = 28). Most pregnancies were uneventful (n = 23; 59 %); new or worsening symptoms were noted in 9 (23 %): 6 palpitations/PVCs and 3 fatigue/dyspnea. A single sustained VT or appropriate ICD therapy occurred in 5 pregnancies (13 %): 3 first trimester sustained VTs (ARVD/C not yet established), 1 second trimester anti-tachycardia pacing (ARVD/C established) and 1 first trimester ICD discharge in a woman with a history of sustained VT. In contrast, 9 other pregnancies in women with VT/ICD discharge history were without events. AHA Class C heart failure (HF) developed in 2 pregnancies (5 %), in women with either biventricular structural disease or tricuspid valve disease pre-pregnancy. They were managed outpatient and are stable 2 and 5 years post-delivery. In 9 other pregnancies with significant right ventricular structural disease, no HF developed. All pregnancies resulted in live-born children without major obstetric complications. Of 11 C-sections (28 %), only 1 was exclusively ARVD/C-related (HF). At last follow-up all children were healthy (0–23 years old); mothers had no cardiac mortality or transplant. Conclusion: Although caution is warranted in women with established biventricular or valve disease, pregnancy and delivery appear to be reasonably safe in ARVD/C, especially when it is recognized beforehand. With adequate guidance and treatment, a favorable outcome for both mother and child is generally obtained.

8–4 Abstract 07–15

46 ARRHYTHMOGENIC RIGHT VENTRICLAR DYSPLASIA DURING PREGNANCY: RETROSPECTIVE STUDY OF 21 PATIENTS

Emilie Varlet¹, Jacky Nizard², Guillaume Duthoit², Veronique Fressart², Nicolas Badenco², Xavier Waintraub², Caroline Himbert², Carole Maupain², Thomas Chastre², Françoise Hidden-Lucet², Estelle Gandjbakhch²

¹ Hopital Bichat, Paris, France; ² Hopital La Pitie Salpetriere, Paris, France

Introduction—Arrhythmogenic right ventricular dysplasia (ARVD) is an inherited heart disease responsible for life-threatening ventricular arrhythmias. There are few data concerning complications associated with this disease during pregnancy. In this study, we aimed to assess the risk of ventricular arrhythmias in pregnant mothers and the impact of ARVD and of anti-arrhythmic drug-therapy in newborn children. Methods and results—We included all female patients with ARVD followed at La Pitié Salpêtrière’s hospital who had a pregnancy. We retrospectively collected clinical and para-clinical characteristics of mothers at the time of pregnancy or at the time of ARVD diagnosis. We recorded all cardiac events that occurred during pregnancy, birth or post-partum period, cardiac events in children and maternal anti-arrhythmic drug therapy during pregnancy. Fifty-eight pregnancies (21 patients) between 1968 and 2013 were identified. Altogether, seven cardiac events (12.1 %) including two serious rhythmic events (ventricular tachycardia, 3.4 %) occurred during pregnancy with no serious consequences on mother or children. There was a non-significant trend toward more cardiac events in non-localized forms (23.8 % versus 5.4 %, p = 0.09) and arrhythmogenic forms (14.9 % versus 0 %, p = 0.33). Neither hemodynamic complications nor rhythmic events during delivery or postpartum period were observed. The rate of cardiac events under the age of 25 was high in children (eight events, 13.8 %), including two unexplained deaths under the age of 1 (3.4 %) and three sudden cardiac deaths (5.2 %, with a mean age of 17.7 ± 5.1). Anti-arrhythmic drug therapy during pregnancy was associated with a lower birth weight (2598.2 ± 807.8 g versus 3394.5 ± 544.3 g; p = 0.04) with no other consequences. Conclusion—ARVD is associated with a low rate of serious rhythmic events during pregnancy and safe delivery. The risk of rhythmic event seems poorly predictable and supports the continued use of anti-arrhythmic drug therapy during pregnancy. Monitoring of children after birth appears highly important considering the risk of cardiac events.

8–5 Abstract 07–14

47 PREDICTIVE VALUE OF LOCAL PROLONGED ELECTRO-MECHANICAL INTERVAL IN THE CONCEALED STAGE OF ARRHYTHMOGENIC RIGHT VENTRICULAR DYSPLASIA/CARDIOMYOPATHY

Thomas P Mast¹, Arco J Teske¹, Anneline S Te Riele¹, Judith A Groeneweg¹, Jeroen F Heijden van der¹, Birgitta K Velthuis¹, Peter Loh¹, Pieter A Doevendans¹, Dennis Dooijes¹, Jaques M Bakker de², Richard N Hauer³, Maarten J Cramer¹

¹ UMC Utrecht, Utrecht, Netherlands; ² AMC Amsterdam, Amsterdam, Netherlands; ³ ICIN - Netherlands Heart Institute, Utrecht, Netherlands

Introduction: The concealed stage of arrhythmogenic right ventricular dysplasia/cardiomyopathy (ARVD/C) is associated with increased risk of sudden death. However, at this stage, disease detection and risk stratification are hampered by paucity of criteria. Activation delay (AD) is a hallmark of arrhythmogenesis in ARVD/C. Echocardiographic deformation imaging may unmask AD in the absence of electrocardiographic and structural abnormalities. Methods: Three groups were compared (1) symptomatic definite desmosomal mutation-positive ARVD/C patients (n = 52), (2) asymptomatic desmosomal mutation carriers (AMC) not fulfilling ARVD/C diagnosis according to the Task-Force criteria (TFC) and without VT and premature ventricular complexes (PVC) > 500/24 h (n = 33) and (3) healthy controls (n = 30). All groups underwent echocardiographic deformation imaging of the right ventricular (RV) free wall and ECG recording according the TFC. As surrogate for local AD, the electro-mechanical interval (EMI) was measured, defined as time between first ECG-detected electrical deflection and local onset of mechanical shortening. Arrhythmic outcome (VT, PVC count) of all mutation carriers was correlated to EMI and electrocardiographic TFC depolarization/repolarization criteria. Results: Mean EMI was prolonged in all RV segments in ARVD/C patients compared to controls. In AMC, prolonged EMI was detected in the subtricuspid area in 18/33 subjects and occurred isolated (absence of ECG and imaging criteria) in 10/33 AMC. Terminal activation duration (TAD) ≥ 55 ms was the only ECG abnormality found in this group (10/33). After a mean follow-up of 3.4 ± 2.7 years, 8/33 subjects experienced an increase in ventricular arrhythmic burden. Prolonged subtricuspid EMI at baseline was the only parameter significantly correlated to arrhythmogenesis during follow-up (Figure 1). Conclusion: Deformation imaging reveals AD in both ARVD/C patients and AMC. In AMC, prolonged EMI in the subtricuspid region is often detected without any additional abnormalities. Prolonged EMI in the subtricuspid area is a new noninvasive parameter unmasking AD in the concealed ARVD/C stage and may contribute to risk stratification.

8–6 Abstract 03–12

48 A NEW RYANODINE RECEPTOR MUTATION ILLUSTRATES THE NEED FOR FAMILY-CENTERED CARE AND GENETIC TESTING IN PATIENTS WITH FAMILIAL ARRHYTHMOGENIC DISORDERS

Cordula M Wolf¹, Isabel Deisenhofer¹, Michaela Horndasch¹, Heide Seidel¹, Peter Ewert¹, Gabriele Hessling¹

¹ German Heart Centre Munich/Technical University Munich, Munich, Germany

Background: Despite an increasing body of knowledge on the genetic basis of familial arrhythmogenic disorders, the diagnosis of those diseases remains a clinical challenge. Genetic testing can identify patients at risk and avoid sudden arrhythmic death by appropriate management. Purpose of study: This case series describes a family in which two children and their mother experienced repeated stress-induced ventricular arrhythmias causing syncope, aborted sudden death, and appropriate implantable cardiac defibrillator (ICD) discharges, starting at the age of 12 years. The maternal grandmother had died suddenly at the age of 21 years. Methods: DNA was extracted from blood of all three patients. All 105 exons of the Ryanodine receptor isoform 2 (RYR2) gene, including slice-sites, were amplified by polymerase chain reaction, and double-stranded DNA sequencing analysis was performed. The mutation was confirmed by second sequencing of an independent DNA-isolate. Results: Clinical testing of the affected individuals revealed normal physical exam and cardiac anatomy in all patients, normal electrocardiogram (ECG) findings in the mother and the daughter, and an epsilon wave at the end of the QRS complex at the son’s ECG. Stress testing showed polymorphic ventricular beats and tachycardia in all three patients. Biomarker testing discovered a novel mutation in the RYR2 gene, coding for the cardiac sarcoplasmic reticulum calcium release channel ryanodine receptor 2 protein. The mutation was a heterozygous substitution in exon 46 in the gene, resulting in the replacement of a glycine with a valine amino acid in the highly conserved domain two of the protein (c.7025G > T; pGly2342Val; Exon 46, RYR2 gene). This mutation was not found in the Human Gene Mutation Database (HGMD professional). The diagnosis of catecholaminergic polymorphic ventricular tachycardia, an autosomal-dominant inherited arrhythmic disorder, was made. Patients were started on beta-blocker and/or flecainide therapy and since then did not experience any malignant events or ICD discharges. Conclusion: This identification of a novel mutation contributes to the growing genetic database for familial arrhythmogenic disorders and underlines that molecular testing and genetic consultation of the entire family should be performed early in disease management. A genetic diagnosis allows optimal patient management, identifies relatives at risk for sudden death and allows initiation of preventive measures in those individuals.

Abstract oral session 9: Atrial fibrillation mechanisms I

Tuesday, April 21, 2015, 8:30 AM–10:00 AM

9–1 Abstract 01–21

49 A NOVEL AUTOMATED METHOD FOR DETECTING NEAR-INSTANTANEOUS RE-INITIATION OF ATRIAL FIBRILLATION

Caroline H Roney¹, Chris D Cantwell¹, Norman A Qureshi¹, Michael T Debney¹, Prapa Kanagaratnam¹, Jennifer H Siggers¹, Nicholas S Peters¹, Fu Siong Ng¹

¹ Imperial College London, London, UK

Introduction: During atrial fibrillation (AF), it is often difficult to distinguish continuous rotor/multiple wavelet activity from rapid reinitiation of AF following termination. We aimed to develop a novel computational method for identifying foci responsible for near-instantaneous reinitiation of AF. Methods: AF wavefront dynamics were analysed over 80 s for four optically mapped canine cholinergic AF preparations. Phase singularities (PS) were identified and tracked over time in order to calculate lifetimes and number of rotations (Fig. A). Active pixels were identified (isophase = −pi/2); instances of zero active pixels were used to identify when the arrhythmia terminates and new instances were used to identify focal sources of reinitiation (Fig. B). Results: Our method successfully tracked locations of PSs and identified areas of reinitiations of AF in all four experimental preparations. Near-instantaneous reinitiations of AF were important in sustaining AF in three of the preparations, where incidence of arrhythmia termination was higher (0.53, 0.64, 0.39 vs 0.08/s), whilst AF in the final preparation was primarily driven by rotor activity (PS density 814 ± 334 vs 615 ± 320, 454 ± 226, 593 ± 279/cm²/s). Our algorithm detected single stable trigger foci in two preparations, which were responsible for rapid reinitiation of AF following termination (Fig). Conclusion: We have developed a novel method for determining the interactions between different AF mechanisms, capable of detecting near-instantaneous re-initiations of AF and locating these foci critical in sustaining the arrhythmia. This method may have clinical utility in guiding ablative therapy towards foci responsible for sustaining AF.

9–2 Abstract 14–21

50 DETERMINING THE RELATIONSHIP BETWEEN RESOLUTION REQUIREMENTS AND WAVEFRONT SPATIAL WAVELENGTH FOR IDENTIFYING ROTORS, FOCI AND MULTIPLE WAVELETS

Caroline H Roney¹, Chris D Cantwell¹, Rheeda L Ali¹, Norman A Qureshi¹, Eugene TY Chang¹, Phang Boon Lim¹, Spencer J Sherwin¹, Jennifer H Siggers¹, Fu Siong Ng¹, Nicholas S Peters¹

¹ Imperial College London, London, UK

Introduction: It is important to have adequate data resolution to distinguish the mechanisms for human atrial fibrillation (AF), which are a subject of much debate (drivers vs. multiple wavelets), although the minimum resolution to distinguish mechanisms is unclear. Resolution requirements for a given rhythm depend on the distance between successive wavefronts (the spatial wavelength). We determined this relationship to give the resolution requirements for identification of the underlying rhythm as a function of the spatial wavelength, together with a method for estimating the spatial wavelength. Methods: Simulations of rotors and focal sources with the spatial wavelength within the range for human AF (n = 9, range 32–78 mm; downsampling range 0.1–25 mm) were used to estimate the minimum number of points (N) per spatial wavelength. Spatial wavelength was estimated (conduction velocity × cycle length), and the number of points required for estimation was investigated. Realistic catheter arrangements (spiral, circular, five-spline and basket) were compared. Results: The minimum value of N necessary to identify a rotor were as follows: 2.5 (for visual identification), 2.7 (for determining rotor core location with a threshold distance of 4 mm) and 3.1 (for a distribution of false phase singularity detections below threshold). Focal sources could be detected with N = 3.3 (visual), N = 1.6 (maximum divergence location). The spatial wavelength was determined accurately using 7 points. When placed over the rotor core, all of the catheters performed well (core location error for wavelength of 33.5 mm: spiral 0.7 mm, circular 3.5 mm, five-spline 0.5 mm; for wavelength of 75.2 mm: basket 5.4 mm, Fig). Conclusions: For the range of spatial wavelengths seen in human AF all commonly used catheters offer sufficient resolution to distinguish rotors and focal sources. A high-density-mapping catheter is required to accurately determine spatial wavelength.

9–3 Abstract 14–20

51 EXCESSIVE ATRIAL ECTOPY AND SHORT RUNS INCREASE THE RISK OF STROKE BEYOND INCIDENT ATRIAL FIBRILLATION

Bjørn Larsen¹, Preman Kumarathurai¹, Julie Falkenberg¹, Olav Wendelboe¹, Ahmad Sajadieh¹

¹ Copenhagen University Hospital of Bispebjerg, København N, Denmark

Background: About 30 % of ischemic strokes are of unknown source. Increased atrial ectopy, which has shown to increase the risk of atrial fibrillation, could be one source. However, the absolute risk of stroke in these subjects is unknown, and likewise, it is not known whether they present with clinical atrial fibrillation before any stroke or with stroke as the first clinical manifestation. We aimed to examine whether increased atrial ectopy and short runs increases the risk of stroke beyond incident atrial fibrillation (AF). Furthermore, we estimated the absolute risk of stroke in these subjects. Methods: The study is based on 15-year follow-up of the Copenhagen Holter Study cohort with 678 men and women aged between 55 and 75 years, with no prior history of cardiovascular disease, stroke or atrial fibrillation. Subjects had 48-h ambulatory ECG recording, fasting blood work, and clinical examination. According to previous studies, excessive supraventricular ectopic activity (ESVEA) was defined as either ≥30 premature atrial contractions (PACs) per hour or any runs of ≥20 PACs. Results: During the median follow-up of 14.4 years, ischemic stroke occurred in 73 subjects in which 21 had ESVEA at baseline (hazard ratio, 2.91; 95 % confidence interval, 1.77–4.90). Censoring at time of AF, ESVEA remained associated with stroke after adjusting for relevant baseline risk factors (hazard ratio, 1.96; 95 % confidence interval, 1.10–3.49). The absolute risk of stroke in subjects with ESVEA and a CHA2DS2VASC score of ≥2 were 2.4 % per year, which is comparable to the risk observed in AF. Day-to-day analysis showed that ESVEA was a consistent finding. Conclusion: ESVEA increased the risk of ischemic stroke beyond manifest atrial fibrillation in this middle-aged and elderly population. Stroke was often the first clinical presentation rather than atrial fibrillation in these subjects. ESVEA was a clinically stable finding, which seemed to confer the same absolute risk as atrial fibrillation.

9–4 Abstract 15–26

52 ALTERNATIVE TO CURRENT INTERVENTIONAL RATIONALES FOR PERSISTENT ATRIAL FIBRILLATION: RIGHT ATRIAL ISOLATION.

Gerard Guiraudon¹, Douglas Jones¹

¹ University of Western Ontarion, London-Ontario, Canada

Introduction: The goal of surgical or catheter-based interventions for atrial fibrillation (AF) is to restore normal cardiac function, i.e., restoration of normal ventricular function, in particular left ventricular (LV) function, since good LV function can sustain the entire circulatory need, including atrial hemodynamics. Restoring cardiac physiology: Normal LV function requires a normal chronotropic response with early activation by the Purkinje system of the papillary muscles for the earliest closing of the mitral valve. The LV is an active suction pump that, in each beat, aspirates the entire left atrial (LA) volume. Indeed, we recently, documented that the LV stroke volume is equal to the LA prediastolic volume. Therefore, the explosive suction of the LV, combined with LA recoil, allows complete flushing of the LA. However, irregular LV rhythm disables effective flushing of the LA, a major cause of thrombosis. Restoring normal LV function in chronic or persistent AF can be achieved by permanently ablating the AF anatomical substrate using multiple catheter sessions or surgical access or focusing only on protecting the sinus node-AV node-His-Purkinje system by isolating, in part or in full, the right atrium (RA) from the fibrillating LA. The experience with the Corridor operation, which is a variety of RA isolation, documented excellent cardiac function with normal flushing of the fibrillating LA. RA isolation: Recent publications have documented that multiple extensive catheter ablations of the LA result in normal LA physiology as documented for the Corridor or RA isolation: the three approaches listed above produce identical cardiac physiology. The advantages of RA isolation include the following: (a) an intervention focusing on discrete, well-defined targets, i.e. the three discrete interatrial bundles, the Bachmann, the coronary sinus and the LA-AV nodal bundles; (b) a single shot intervention that can be delivered, by catheter or surgical access, easily combined with open heart access and easily performed via minimally invasive access for lone AF; (c) the single-shot catheter ablation should increase the effectiveness of electrophysiology procedures and decrease patient wait times, and (d) last but a critical advantage, RA access will eliminate the added risk of stoke which is currently associated with extensive LA catheter ablation. Conclusions: We have presented arguments in support of RA isolation as an addition and alternative to current ablative rationales. RA isolation may become a first choice for persistent AF, and with more experience, be a valid alternative for paroxysmal AF

9–5 Abstract 15–19

53 A CELLULAR AUTOMATON MODEL TO IDENTIFY CRITICAL SITES IN ATRIAL FIBRILLATION

Kishan Manani¹, Kim Christensen¹, Nicholas S Peters¹

¹ Imperial College London, London, UK

Background: Identifying critical sites of the myocardial substrate which initiate and maintain atrial fibrillation is of therapeutic significance. We implemented a simple two-dimensional computer model, a cellular automaton (CA), of the myocardial substrate which shows that particular structures are responsible for the initiation and maintenance of fibrillatory activity. Results: A CA model of the myocardial substrate is generated by randomly assigning the connectivity between cells. This generates a substrate which mimics the myocardial microstructure. In addition to this, electrical cellular dysfunction is incorporated by introducing a degree of heterogeneity in cell firing. The interaction between these two variables generates a substrate in which planar wave fronts of activation will either spontaneously evolve into fibrillation or not, and in which the resulting fibrillation will either persist or spontaneously terminate. We found that fibrillatory behaviour could be terminated when particular structures within the substrate are made unexcitable. The transition from paroxysmal to persistent atrial fibrillation in the model can be explained by an increase in the number of critical sites. Conclusions: We have produced a simple CA model of the myocardial substrate which exhibits a wide range of phenomenological behaviour associated with atrial fibrillation. The existence of critical structures within the model raises the possibility that such structures might be detected in real myocardium by clinically accessible data such as electrograms.

9–6 Abstract 02–13

54 CHARACTERISATION OF BASELINE STRUCTURE OF CANINE LEFT ATRIUM DURING ACUTE INDUCED AF

Christian Eichhorn¹, Rasheda A Chowdhury¹, Michael T Debney¹, Norman A Qureshi¹, Caroline H Roney¹, Nicholas S Peters¹, Fu Siong Ng¹

¹ Imperial College, London, UK

Background: Recent clinical studies have supported a role for focal drivers in maintaining atrial fibrillation (AF), with some studies showing that these drivers/rotors have a preference for anchoring to specific sites in the left atrium (LA). We hypothesized that regional heterogeneities in fibrosis and gap junctional cell-to-cell coupling in the LA may contribute towards determining the locations of these drivers in the LA. We performed regional analysis of cardiac gap junctions and fibrosis in the canine LA to assess this hypothesis. Methods: Five explanted canine left atria were used for these studies, with the LA divided into nine regions (Figure) and frozen for subsequent analysis. LA structure was assessed by immunohistochemistry of connexin 40 and 43 proteins and autofluorescence of fibrosis. For fibrosis, the total amount of fibrosis, the proportion of stringy (interstitial) and circular (scar) fibrosis were analysed, and for connexins, the heterogeneity of connexin 40, the colocalisation of connexin 40 and 43 in intercalated disks, the size of en-face intercalated disks and the proportional occupation by connexin43 of these en-face disks were calculated. Results: Gap junctional disk size was increased in the mid-posterior wall of the LA compared with other regions (p = 0.03). We did not detect any other regional differences in fibrosis quantity/proportions nor in connexin heterogeneity or colocalisation. Conclusion: There were detectable differences in gap junctional disk size between regions in the LA as assessed by immunohistochemistry, though we detected no other spatial heterogeneities of fibrosis and connexins. Correlation of the structural data above with optical mapping data of AF in these preparations may help to explain if any spatial structural heterogeneities contribute to the locations of drivers in AF.

Abstract oral session 10: Atrial arrhythmia mechanisms II

Tuesday, April 21, 2015, 8:30 AM–10:00 AM

10–1 Abstract 02–10

55 PARTICIPATION OF MIRNAS IN ATRIAL ARRHYTHMOGENIC STRUCTURAL REMODELING IN PATIENTS WITH ATRIAL FIBRILLATION

Marina Eremeeva¹, Amina Ibragimova¹, Tatiana Sukhacheva¹, Valentin Vaskovskiy¹, Amiran Revishvili¹

¹ Bakoulev Center for Cardiovascular Surgery, Moscow, Russia

Aim: We aim to determine the role of key stress-responsive miRNAs involved in AF and induced atrial arrhythmogenic structural remodeling. Methods: The study included 16 patients (age 51.3 ± 9.8) with long-standing atrial fibrillation (LSAF) undergone bipolar RF maze procedure and 10 patients (age 49 ± 7.9) in the control group with sinus rhythm (SR) after aortic valve replacement. The level of expression of miRNAs (mir1, mir133a, mir133b, mir208a, mir208b, mir499, mir195, mir29, mir21) in atrial myocardium (intraoperative biopsy of left atrial appendage (LAA) and right atrial appendage (RAA) tissues) by qRT-PCR was analyzed. Morphometric study of LAA and RAA myocardium was performed. Statistical analysis was made using a Mann–Whitney U test, non-parametric Spearman correlation; p < 0.05 was considered significant. Results: The analysis of 9 miRNA expression in the LAA and RAA tissues in LSAF patients showed a significant upregulation in miRNA 208b expression both in RAA (p < 0.01) and in LAA (p < 0.01) compared with the SR group. When comparing LAA and RAA significant differences in miRNA21 expression in LSAF group were determined, the expression level was higher in the LAA (p < 0.05). Screening of LAA and RAA myocardium from LSAF patients revealed a high proportion of interstitial fibrosis (LAA 46.8 ± 10.7 %; RAA 47.2 ± 11.4 %) and lipomatosis. Forty-eight percent of LAA biopsy and 44.4 % of RAA biopsy were involved with isolated atrial amyloid deposits which reacted with anti-alpfa-ANP. The increase in the cardiomyocyte diameter and length were correlated, both parameters did not differ significantly between LAA and RAA, but were higher in LSAF than in SR patients. In 39.5 % LAA biopsy and 45.7 % RAA biopsy from LSAF patients, marked sarcomere loss in cardiomyocytes was detected. LAA cardiomyocyte diameter was larger in patients with increasing size of the LA and cardiomyocyte length was larger in patients with greater duration of AF. Over-expression of mir208b in LSAF patients correlated with the increased interstitial fibrosis and the decreased sarcomere loss in cardiomyocytes. Conclusion: miRNA 208b have a regulatory function in the progression of LSAF and are involved in atrial arrhythmogenic structural remodeling. Identification of key miRNAs in atrial remodeling will advance our understanding of the determinants of AF and suggest novel therapeutic possibilities to prevent clinical AF.

10–2 Abstract 01–14

56 DETERMINANTS OF PREFERENTIAL ROTOR LOCATIONS AND STABILITY IN ATRIAL FIBRILLATION

Fu Siong Ng¹, Caroline H Roney¹, Michael T Debney¹, Christian Eichhorn¹, Arun Nachiappan¹, Norman Qureshi¹, Rasheda A Chowdhury¹, Alexander Lyon¹, Nicholas S Peters¹

¹ Imperial College London, London, UK

Introduction: Rotors have been shown to drive atrial fibrillation (AF) and targeting these sites has emerged as an ablation strategy. However, factors that influence the locations and stability of rotors and spiral waves in AF remain unclear and have mainly be studied in silico or in cell monolayers, which lack the anatomical and structural complexities of real atria. We experimentally assessed the relative importance of various anatomical, structural and functional factors in determining rotor locations in the left atrium. Methods: Isolated, perfused canine left atrial preparations (n = 6) were optically mapped at baseline and after AF induction with pacing and acetylcholine. Rotor core locations were tracked using a novel computational algorithm for 80 s of AF. The left atria were then divided into nine regions for Cx43 immunohistochemistry and fibrosis analysis. Conduction and repolarization data from optical mapping, and Cx43 and fibrosis data were compared between regions with high and low rotor densities to assess for determinants of rotor locations. Results: Rotors in AF locate preferentially to specific regions of the left atrium (Figure), though their distributions vary between hearts. Areas of high rotor densities are often closely associated with pulmonary vein (PV) ostia. There were no differences between Cx43 and fibrosis quantity/distribution between areas of high and low rotor density. There were slower AP upstrokes (p < 0.05) and trends towards shorter APDs (APD75 at 300 ms, 41 ± 8 ms vs. 63 ± 12 ms, p = 0.1) in areas with high incidences of rotors. Conclusions: There are preferential locations for AF rotors in the left atrium. Anatomical (locations of PVs) and functional factors (spatial heterogeneities of repolarization and conduction) are more important in determining rotor sites than structural factors such as regions of fibrosis. Identification of the determinants of preferential rotor sites can help optimize ablative therapy for AF.

10–3 Abstract 01–11

57 ANTIARRHYTHMIC MECHANISMS OF SK CHANNEL INHIBITION IN THE RAT ATRIUM

Lasse Skibsbye¹, Xiaodong Wang¹, Lene Axelsen¹, Morten Schak Nielsen¹, Morten Grunnet¹, Bo Bentzen¹, Thomas Jespersen¹

¹ University of Copenhagen, Copenhagen, Denmark

Introduction: SK channels have functional importance in the cardiac atrium of many species, including humans. Pharmacological blockage of SK channels has been reported to be antiarrhythmic in different animal models of atrial fibrillation; however, the exact antiarrhythmic mechanism of SK channel inhibition remains unclear. Objectives: We speculated that together with a direct inhibition of repolarizing SK current, the previously observed depolarization of the atrial resting membrane potential (RMP) after SK channel inhibition reduces sodium channel availability and thereby prolongs the effective refractory period (ERP) and slows conduction velocity. We therefore aimed at elucidating these properties of SK channel inhibition and the underlying antiarrhythmic mechanisms by using microelectrode action potential recordings and conduction velocity measurements in isolated rat atrium. Moreover, automated patch-clamping (Qpatch) was used to access sodium current inhibition. Results: Runs of atrial fibrillation observed in the isolated right atrium was not inducible after pharmacological SK channel inhibition. The SK channel inhibitor N-(pyridin-2-yl)-4-(pyridin-2-yl)thiazol-2-amine (ICAGEN) exhibited antiarrhythmic effects. Without directly inhibiting sodium channels, ICAGEN induced atrial post-repolarization-refractoriness and slowed conduction velocity. However, due to a marked prolongation of ERP, the calculated wavelength was increased. Furthermore, at increased pacing frequencies, SK channel inhibition showed more prominent effects on sodium channel-dependent parameters. Contractility was not affected. Conclusion: SK channel inhibition modulates multiple parameters of the action potential, including prolongation through direct blockage of the repolarizing SK current, and shifting the resting membrane potential towards more depolarized potentials, which leads to an indirect sodium channel inhibition and ultimately conduction slowing and decreased excitability. Hence, we propose that the antiarrhythmic mechanism of SK channel inhibition is generated both through direct potassium channel block and via indirect sodium channel inhibition.

10–4 Abstract 01–13

58 ELECTROGRAMS ARE MORE THAN THE SUM OF THEIR PARTS—A NEW RAT MODEL OF ATRIAL ARRHYTHMIAS REFUTES THE CRITICAL MASS HYPOTHESIS AND REVEALS NEW INSIGHTS INTO HUMAN ATRIAL FIBRILLATION

Junaid Zaman¹, Pravina Patel¹, Jennifer Simonotto¹, Nicholas Peters¹

¹ Imperial College London, London, UK

Intro: Spontaneous models of AF, especially studying age and blood pressure (BP), are lacking. Small atria were thought not to be able to harbor sufficient path length to sustain re-entrant AF. We hypothesize that the aged rat atrium, especially in the presence of hypertension, is a model substrate with structure function insights relevant to all forms of AF. Methods: Forty normotensive rats (BN) and 40 hypertensive rats (SHR) from 3 to 12 m had ex vivo Langendorff perfusion, recording AF > 30 s using bi-atrial microelectrode arrays (MiEA). AF was mapped using activation time, dominant frequency (DF), organizational index (OI), Shannon entropy (ShEn) and magnitude squared coherence (MSC) and related to fibrosis and connexin 43 (Cx43) levels. Physical summation of the MiEA electrodes was performed to test effect on AF indices using a ‘bridge’. Subsets had non-invasive BP (3–6 m) measured and telemetry implanted (9–12 m) age to check in vivo data. Results: In vivo data confirm the presence of naturally occurring atrial tachycardia (AT) and AF in both rats from 9 m old despite SHR BP elevation from 3 m. Ex vivo BN were equally inducible to AT/AF to SHR throughout. Mean ShEn and MSC correlated with fibrosis but not when the electrodes were bridged to summate output across a 1.5-mm square. Conversely, mean DF and OI showed no correlation with Cx43 unless electrodes were bridged together. Conclusions: (1) BN are a new small animal model of in vivo and ex vivo AT/AF. (2) Age is a more potent risk factor for AF than BP. (3) Cx43 correlates with bridged arrays only and fibrosis individual electrodes only, akin to ‘SD’ and ‘HD’ substrate factors, respectively. (4) This novel finding suggests substrate changes in AF come ‘in and out of focus’ as spatial resolution varies.

10–5 Abstract 01–19

59 THE FUNCTIONAL EXPRESSION OF ELECTROPHYSIOLOGIC PARAMETERS IN THE ORGANIZED VS. DISORGANIZED RHYTHM: A COMPARATIVE ASSESSMENT OF VOLTAGE, CONDUCTION VELOCITY, AND FRACTIONATION DURING ATRIAL FIBRILLATION AND THE PACED RHYTHM IN THE PERSISTENT AF SUBSTRATE

Norman Qureshi¹, Steve Kim², Chris Cantwell¹, Rheeda Ali¹, Caroline Roney¹, Fu Siong Ng¹, Arunashis Sau¹, Rasheda Chowdhury¹, Michael Kao-Wing¹, Sajad Hayat¹, Elaine Lim¹, Ian Wright¹, Nick Linton¹, David Lefroy¹, Zachary Whinnett¹, D Wyn Davies¹, Prapa Kanagaratnam¹, Nicholas Peters¹, Phang Boon Lim¹

¹ Imperial College, London, UK; ² St Jude Medical, St. Paul, MN, USA

Background. The complexities of mapping the spatiotemporal variations in AF limit the understanding of the functional electrophysiological determinants of AF. This study sought to simplify the problem of understanding the electrical properties of AF by assessing the regional electrophysiologic (EP) relationship between AF and the paced rhythm. Methods. Patients undergoing PsAF ablation underwent electroanatomical mapping using a 20-pole spiral catheter. Voltage and fractionation mapping were performed in AF over various left atrial (LA) sites, and following DCCV, voltage and activation mapping during LA pacing (cycle lengths 300/600 ms) were performed over the same sites. Deflections and scores were calculated using an automated custom electrogram (EGM) analysis tool. Results. 35 LA sites were analysed from 12 patients (age 65 ± 11years, LA 41 ± 7 mm, CHADS2VASC2 2.8 (0–6)). At each mapped LA site, the mean peak-to-peak voltage over 8 s in AF (AF-V) correlated with the mean paced voltages (P-V) (300 and 600 ms) (R ² = 0.5114 p < 0.0001 and R ² = 0.4742 p < 0.0001, respectively). There was also a positive correlation of the mean of both AF-V and P-V (300/600 ms) to the percentage of fractionated electrograms (%EGMs with NavX CFE mean score <80 ms) at each site [R²(AF) = 0.4310, p < 0.0001, R²(300 ms) = 0.4310, p < 0.001 and R²(600 ms) = 0.498, p < 0.001]. There were poor correlations between conduction velocity (CV) at both 300 and 600 ms LA pacing, with mean AF-V, P-V and percentage fractionated EGMs. Conclusion. Voltages in AF correlated to that in the paced rhythm and to fractionation of EGMs, but not CV. The EP substrate of AF can be interrogated in the paced rhythm and could provide crucial insights into the underlying mechanisms of AF.

10–6 Abstract 02–12

60 VERY-LOW-DENSITY LIPOPROTEIN OF INDIVIDUALS WITH METABOLIC SYNDROME SHORTENS ATRIAL ACTION POTENTIAL DURATION BY CHANGING CALCIUM TRANSIENT

Hsiang-Chun Lee¹, Wei Chi¹, Hsin-Ting Lin¹, I-Hsin Liu¹, Liang-Yin Ke², Chu-Huang Chen², Bin-Nan Wu³, Sheng-Hsiung Sheu¹

¹ Division of Cardiology, Department of Internal Medicine, Kaohsiung Medical University Hospital, Kaohsiung Medical University, Kaohsiung, Taiwan; ² Center of Lipid Biosciences, Kaohsiung Medical University (KMU) Hospital, KMU, Kaohsiung, Taiwan; ³ Department of Pharmacology, College of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan

Background: Compared to that of healthy normal subjects, plasma very-low-density lipoprotein (VLDL) of patients with the metabolic syndrome (MetS) has been shown to be more electronegative and atherogenic. Given the association between MetS and increased prevalence of atrial fibrillation (AF), we investigated the mechanistic role of VLDL in the AF pathogenesis. Methods: We extracted VLDL via peripheral blood obtained from normal, healthy volunteers and MetS individuals. The normal-VLDL and MetS-VLDL samples were treated to HL-1 atrial cardiomyocytes, respectively, for 12 h before experiments. Whole-cell patch clamp was used for monitoring the action potentials and voltage-gated L-type calcium currents (ICaL). Calcium image with Fura-4-AM Ca2+ indicator was applied for the intracellular calcium measurements. Results: MetS-VLDL-treated HL-1 cells exhibited significantly higher densities of ICaL. MetS-VLDL shifted the activation curve of ICaL toward more negative membrane potentials. Intracellular calcium signals were significantly enhanced by MetS-VLDL but not by normal-VLDL. MetS-VLDL significantly shortened action potential durations (MetS-VLDL 178.1 ± 32.0 ms vs control 257.2 ± 52.7 ms; P = 0.0017). Additionally, frequent occurrences of early after-depolarization on action potentials were noted in MetS-VLDL-treated HL-1 cells. Conclusions: The VLDL of MetS individuals augmented repolarizing calcium currents, increased intracellular calcium release, and significantly shortened action potentials. These changes may contribute in coordination to increased AF vulnerability in MetS.

Abstract oral session 11: Management of atrial arrhythmias

Tuesday, April 21, 2015, 8:30 AM-10:00 AM

11–1 Abstract 15–32

61 NONINVASIVE ELECTROCARDIOGRAPHIC IMAGING AND CATHETER ABLATION OF PERSISTENT ATRIAL FIBRILLATION

Amiran Revishvili¹, Oleg Sopov¹, Evgenii Labartkava¹, Vitalii Kalinin¹, George Matsonashvili¹

¹ Bakoulev Scientific Center for Cardiovascular Surgery, Moscow, Russia

Introduction. Recent achievements in noninvasive electrocardiographic (ECG) imaging allowed its extensive use in diagnostics and treatment of different arrhythmias. This study aimed to identify sources of initiation and maintenance of atrial fibrillation (AF) by means of surface ECG-based mapping technology combined with CT scan or MRI and to evaluate results of ablation guided by these maps. Methods. We applied noninvasive mapping using 240-lead ECG combined with CT scan- or MRI-based anatomy (Amycard LCC) to 23 patients (15 male/8 female) with persistent AF (mean continuous AF duration 4 ± 2 months). Fragments with spontaneous pauses (prolonged R-R interval) during AF were selected for mapping before procedure. We evaluated electrical activity in the left and right atrium and atrial septum using specific algorithm. In 22 patients, radiofrequency (RF) ablation was performed at the sites of sustained circular electrical activity followed by antral pulmonary vein (PV) isolation. One patient underwent Maze IV procedure due to thrombus in left atrial appendage. Results. During evaluation of electrical activity in the left and right atrium, we found from 2 to 4 simultaneously coexisting «rotors». RF application in this areas resulted in alteration of frequency or direction of electrical activity registered at CS or Lasso catheters. Targeted ablation terminated AF and maintained sinus rhythm in 8 patients (35 %). Mean RF application time was 26 ± 18 min. In 15 patients (65 %), we registered prolongation of arrhythmia cycle length but its termination was achieved only after pharmacological or electrical cardioversion. Conclusion. In all patients (100 %), we observed two rotors (a system of two rotors connected of the excitation wave front). In 13 patients (56 %), we observed the second intermittent pair of rotors. In all patient rotors, movement includes two types of drifting: slow drifting (when rotors are situated in abnormal myocardium zones) and fast drifting (as result of wave front collision with refractory myocardium). Sinus rhythm recovery observations support simulation based theory of scroll wave collapse. Ablation of rotors works if rotors “drop the anchor” for a long time (>4 rotation cycles) and “anchoring zones” are narrow. Initial experience with noninvasive ECG imaging using 3D-4D mapping system combined with CT scan or MRI shows its clinical utility, feasibility to provide noninvasive evaluation and features of arrhythmogenic areas and to increase effectiveness of interventional AF treatment.

11–2 Abstract 15–34

62 MEASUREMENT OF THE ACTIVATED CLOTTING TIME (ACT) TO CONTROL ANTICOAGULATION DURING PULMONARY VEIN ISOLATION: A COMPARISON OF METHODS

Reinhard Höltgen¹, Martin Brück², Dirk Bandorski³, Jessica Hirsch⁴, Marcus Wieczorek¹

¹ I. Medizinische Klinik - Kardiologie/Elektrophysiologie; St. Agnes-Hospital, Bocholt, Germany; ² Medizinische Klinik I; Klinikum Wetzlar, Wetzlar, Germany; ³ Medizinische Klinik 2, Universitätsklinikum Gießen, Gießen, Germany; ⁴ Institut für Medizinsche Biometrie und Epidemiologie; Universität Witten/Herdecke, Witten, Germany

Introduction: Effective anticoagulation is a cornerstone to reduce the number of thromboembolic complications during pulmonary vein isolation (PVI). The poignancy of anticoagulation is monitored by measurement of the ACT. Yet, a methodological gold standard for the determination of the ACT is not available. The aim of the study was to clarify, if different methods for the determination of the ACT lead to different results. Patients and methods: In 31 consecutive patients (pts) (age 58 ± 12 years), ACT-measurement was conducted during PVI in intervals of 15 min. A total amount of 150 blood samples was controlled simultaneously, using two different measuring devices: ACT-Messgerät Hemochron Signature Plus, Keller Medical (ACT 1), and ACT-Plus, Medtronic Inc. (ACT 2). All pts were under uninterrupted anticoagulation with Phenprocoumon (Ph). During PVI, unfractionated heparin was applied repetitively, following a predefined protocol in order to lift the ACT to a level of ≥ 350 s. Results: For both measuring methods, we found an inverse correlation between the initial international normalized ratio (INR) and the average cumulative dose of heparin. Between ACT-measurements by ACT 1 (343.17 ± 96.09 s) and ACT 2 (313.85 ± 111.61), a highly significant difference (p < 0.001) could be proven. The median by ACT 1 was 28 s longer than by ACT 2. Pts with an INR < 1.8 showed significantly longer ACT values, when tested with ACT 1 compared to those tested with ACT 2, whereas in the two groups with higher INR-levels (INR 1.8–2.0 or INR > 2.0), only a non-significant trend could be observed as follows:

	INR < 1.8	INR 1.8–2.0	INR > 2.0
ACT 1	360.52 ± 133.249	311.56 ± 73.284	348.58 ± 90.744
ACT 2	311.67 ± 131.192	297.76 ± 91.123	319.32 ± 112.483
P value	0.02	n.s.	n.s.

Conclusions: The utilization of different methods to measure the ACT in identical blood samples leads to significantly different results. This difference is mostly pronounced in pts with sub-therapeutic oral anticoagulation. In an intra-individual comparison, the different results of the ACT measurements lead to a relevantly different assessment of the dosage of heparin, applied during PVI-procedure.

11–3 Abstract 15–12

63 PREDICTORS OF CEREBRAL MICROEMBOLIZATION DURING PHASED RADIOFREQUENCY ABLATION OF ATRIAL FIBRILLATION: ANALYSIS OF BIOPHYSICAL PARAMETERS FROM THE ABLATION GENERATOR.

Edina Nagy-Baló¹, Alexandra Kiss¹, Catherine Condie², Mark Stewart², Zoltán Csnádi¹

¹ University of Debrecen, Institution of Cardiology, Debrecen, Hungary; ² Medtronic Inc., Minneapolis, MN, USA

BACKGROUND: Pulmonary vein isolation with phased radiofrequency current and use of a pulmonary vein ablation catheter (PVAC) has recently been associated with a high incidence of clinically silent brain infarcts on diffusion-weighted magnetic resonance imaging and a high microembolic signal (MES) count detected by transcranial Doppler. OBJECTIVE: The purpose of this study was to investigate the potential correlation between different biophysical parameters of energy delivery (ED) and MES generation during PVAC ablation. METHODS: MES counts during consecutive PVAC ablations were recorded for each ED and time stamped for correlation with temperature, power, and impedance data from the GENius 14.4 generator. Additionally, catheter-tissue contact was characterized by the template deviation score, calculated by comparing the temperature curve with an ideal template representing good contact, and by the respiratory contact failure score, to quantify temperature variations indicative of intermittent contact due to respiration. RESULTS: A total of 834 EDs during 48 PVAC ablations were analyzed. A significant increase in MES count was associated with a lower average temperature, a temperature integral over 62 °C, a higher average power, the total energy delivered, higher respiration and template deviation scores (P < 0.0001), and simultaneous ED to the most proximal and distal poles of the PVAC (P < 0.0001). CONCLUSION: MES generation during ablation is related to different indicators of poor electrode-tissue contact, the total power delivered, and the interaction between the most distal and the most proximal electrodes.

11–4 Abstract 15–11

64 REDUCED LEFT ATRIAL COMPLIANCE CONTRIBUTES TO THE RECURRENCE AFTER CATHETER ABLATION IN PATIENTS WITH LONE ATRIAL FIBRILLATION

Junbeom Park¹, Jin-Kyu Park¹, Jae-Sun Uhm¹, Boyoung Joung¹, Moon-Hyoung Lee¹, Hui-Nam Pak¹

¹ Yonsei University Health System, Seoul, Republic of Korea

Objective: Stiff left atrial (LA) syndrome was initially reported in post-cardiac surgery patients and known to be associated with low LA compliance. We investigated the physiological and clinical implications of LA compliance, estimated by LA pulse pressure (LApp) among patients with lone AF. Methods: Among 1038 consecutive patients with LA pressure measurements in the Yonsei AF Ablation Cohort, we included 334 patients with lone AF (81.7 % male, 54.1 ± 10.6 years, 77.0 % paroxysmal AF) after excluding those with hypertension, diabetes, systolic or diastolic dysfunction, any structural heart disease, and previous ablation or cardiac surgery. We measured LApp (peak LA pressure [v-wave] − nadir LA pressure [x-wave]) at the beginning of the ablation procedure, and compared the values with clinical imaging parameters and AF recurrence rate. Results: 1. Patients with lone AF were younger (p < 0.001), more likely to be male (p < 0.001), have paroxysmal AF (p < 0.001) and have lower BMI (p = 0.041) and LApp (p < 0.001) compared to those with other diseases. Based on the median value, low LA compliance group (LApp³13mmHg) had a smaller LA volume index (3D-CT; 73.1 ± 19.9 vs. 78.4 ± 19.3 ml/m², p = 0.035) and lower LA voltage (1.2 ± 0.6 vs. 1.4 ± 0.8 mV, p = 0.032) than those with high LA compliance (LApp < 13 mmHg). During a median follow-up of 12 months, LApp³13mmHg was independently associated with clinical recurrence of lone AF (HR = 3.16, 95 %CI 1.146 ∼ 8.711, p = 0.026). Conclusions: Reduced LA compliance estimated by an elevated LApp was associated with smaller LA volume index and lower LA voltage and also independently associated with higher clinical recurrence after catheter ablation in patients with lone AF.

11–5 Abstract 15–27

65 IMPACT OF LEFT ATRIAL LOW VOLTAGE EXTENT ON OUTCOMES AFTER ABLATION FOR PERSISTENT ATRIAL FIBRILLATION

Jeremie Sorrel¹, Amir Jadidi¹, Heiko Lehrmann¹, Thomas Arentz¹

¹ Herzzentrum Bad Krozingen, Bad Krozingen, Germany

Objective: Atrial fibrosis is implicated in maintenance of persistent atrial fibrillation (AF). We hypothesized that the extent of atrial low-voltage areas (low voltage in AF < 0.5 mV) may be predictive for clinical outcomes in patients undergoing ablation for persistent AF. Methods: Seventy-eight consecutive patients with persistent AF (64 ± 8 years old, 68 % male) underwent left atrial (LA) voltage mapping at high density (912 ± 134 sites) in AF using a 20-pole Lasso catheter in combination with Velocity (SJM) or Carto3 (BW). If AF persisted after completion of PV isolation, patients underwent additional ablation of prolonged and fractionated electrograms within low-voltage sites <0.5 mV. Single procedural recurrence rate (AF and atrial tachycardia (AT)) was assessed at 6, 9 and 12 months by 24 h ECG. Results: The mean extent of LA low voltage was 35 ± 27 % for the total study group. Arrhythmia freedom (AF and AT) was maintained in 59/78 (76 %) patients after a single procedure and a mean follow-up of 9 ± 2 months. Arrhythmia freedom was 95 % (20/21) in patients with low extent (<15 %, group A) of LA low voltage vs. 71 % (17/24) in patients with intermediate extent (15–35 %, group B) of LA low voltage and 66 % (22/33) in patients with high extent (>35 %, group C) of LA low voltage (p = 0.02 for A vs C). However, AF freedom did not differ significantly between these three groups (95 % (20/21) group A, vs 75 % (18/24) group B, vs 82 % (27/33) group C (p = 0.23). Conclusion: The baseline extent of LA low-voltage areas in AF predicts rate of arrhythmia freedom after a single ablation for persistent AF. Patients with increased low voltage areas (>35 % of LA surface) present an increased risk for arrhythmia recurrence especially for atrial tachycardia.

11–6 Abstract 18–30

66 ATRIAL TACHYCARDIAS ORIGINATING FROM THE NON-CORONARY CUSPS: THE TEL-AVIV MEDICAL CENTER EXPERIENCE IN 7 PATIENTS.

Yoav Michowitz¹, Raphael Rosso¹, Aharon Glick¹, Sami Viskin¹, Bernard Belhassen¹

¹ Tel-Aviv Medical Center, Tel-Aviv, Israel

Background: Atrial tachycardia (AT) originating from the non-coronary cusp (NCC) has been recently described. Objectives: The study aims to describe the clinical and electrophysiological characteristics of AT originating from the NCC and treated with radiofrequency ablation (RFA) at our center. Methods: Files of patients (pts) with NCC-AT were retrospectively studied. Data were obtained from pts’ charts, ECGs, electrophysiological reports and digital recording systems. Results: Of 101 pts with AT referred for RFA between January 2008 and October 2014, we identified 7 pts (4 females, aged 24–78 years, mean 55 ± 19) with NCC-AT. Clinical symptoms included recurrent episodes of palpitations in 4, syncope in 2 and exercise-test induced AT in 1 pt. Mean rate of the clinical tachycardia was 172 + 40 bpm. Mapping the right atrium during tachycardia revealed earliest activity in the His area in 6 pts and in both the His area and the CS-ostium in 1. The left atrium was also mapped in 2 pts. Retrograde aortic approach was used for mapping the aortic cusps in all pts. Electro-anatomical mapping systems were used in 2 pts. In 2 pts ablation was attempted first in the RA and in 2 also in the LA. The earliest local atrial activation in the NCC preceded the atrial activation in the His area by 29 ± 10 ms. In 4 pts, the AT mimicked AVNRT. Since it was impossible to clearly distinguish the atrial activation pattern in 1 pt, slow pathway ablation was necessary. Ablation was carried out with regular 4-mm and irrigated 3.5-mm ablation catheters (with up to 40-W power) in 4 and 2 pts, respectively. In our first pt, ablation was not attempted. Acute successful ablation was uncomplicated, especially no AV block was observed. During follow-up of 25 ± 22 month, 1 pts had recurrence of AT without medications (excluding the first pt who was not ablated). Conclusions: AT may originate from the NCC. Catheter ablation of this rare arrhythmia is safe and effective.

Abstract oral session 12: Atrial fibrillation ablation III

Tuesday, April 21, 2015, 8:30 AM–10:00 PM

12–1 Abstract 14–16

67 IDIOPATHIC ATRIAL FIBRILLATION, INFLAMMATION, AND CLINICAL RESULTS OF RADIOFREQUENCY ABLATION

Roman Batalov¹, Yulia Rogovskaya¹, Viacheslav Ryabov¹, Roman Tatarskiy¹, Svetlana Sazonova¹, Mikhail Khlinin¹, Sergei Popov¹

¹ RI of cardiology, Tomsk, Russia

The aim of the study was to evaluate the role of inflammation in clinical results of radiofrequency ablation (RFA) of atrial fibrillation (AF). Material and methods. The study comprised 274 patients admitted to clinic with diagnosis of idiopathic form of AF. At the first stage of examination, this diagnosis was confirmed only in 67 (24.5 %) patients. All patients received AF RFA and endomyocardial biopsy study with histological and immunohistochemical determination of the myocardial infiltrating cells and the expression of cardiotropic viral antigens. Catheter treatment efficacy and the presence of early and late recurrences was evaluated. Results. According to endomyocardial biopsy study, histological changes in the right ventricular myocardium were absent in 9 (13.4 %). Signs of myocardial fibrosis were found in 26 (38.8 %) mostly suggesting the presence of perivascular fibrosis in 11 (42.3 %), microfocal fibrosis in 8 (30.8 %), and perimuscular fibrosis in 7 (26.9 %). Inflammatory changes were found in 32 (47.8 %) where 9 (28.1 %) had lymphocytic infiltration. One of these patients (3.1 %) had a combination of the expression of human herpes simplex virus type 2 and Epstein-Barr virus. Among 23 (34.3 %) with myocarditis, viral expression was found in 18 (78.3 %). Expression of three viruses was found in one (5.6 %); two viruses was identified in six (33.3 %); and one viral antigen was found in 11 (61.1 %). Mean duration of follow-up was 19.3 ± 3.7 months. Primary RFA efficacy rate was 88.9 % in patients with intact myocardium, 46.2 % with fibrotic changes of various severities, and 34.4 % in the presence of the criteria for myocarditis. Early recurrences of arrhythmias were absent when myocardium was unchanged. In the presence of fibrotic changes, early recurrences were registered more frequently (53.8 %); late recurrences were less often (34.6 %). In the presence of inflammatory changes, the late recurrences were more frequently (53.1 %) whereas the early recurrences were less often (37.5 %). Conclusion. According to our study, only 24.5 % of patients were free of diseases facilitating the development of arrhythmias. Histological study showed that only 10 % of patients had idiopathic form of arrhythmia, half had inflammatory changes in the myocardium, and the rest of patients presented with fibrotic changes. The presence of inflammatory and fibrotic changes in the myocardium increased the number of early and late recurrences of arrhythmia and, correspondingly, attenuated the efficacy of AF RFA by twofold.

12–2 Abstract 18–33

68 CHARACTERISTICS OF PATIENTS THAT FAILED CATHETER ABLATION OF ATRIAL FIBRILLATION, A SINGLE CENTER EXPERIENCE

C Teunissen¹, J.F. vd Heijden¹, R.J. Hassink¹, W Kassenberg¹, P.A.F.M Doevendans¹, K.P. Loh¹

¹ UMC Utrecht, Utrecht, Netherlands

Introduction: Catheter ablation is a successful treatment option in patients suffering from symptomatic, drug refractory atrial fibrillation (AF). Single-procedure success is modest and patients with AF recurrence usually undergo repeated and sometimes extensive ablations. Patients can be free of tachycardia off antiarrhythmic drugs or achieve clinical benefit with reduced AF burden. Treatment strategy of patients with AF recurrence is influenced by patient’s symptoms and preferences and by physician’s choices. Objectives: The sudty aims to analyze patients with AF recurrences after single or multiple ablations in our center and to characterize patients that ultimately did not benefit from treatment. Methods: From January 2005 to January 2013, 736 consecutive patients (mean age 57 years, 59.5 % paroxysmal AF, 28.4 % persistent AF and 12.1 % longstanding persistent AF) suffering from symptomatic, drug refractory AF underwent catheter ablation. The primary ablation strategy was pulmonary vein antrum isolation. If necessary, substrate modification was added in redo procedures. Results: After single or multiple procedures (follow-up after last procedure 44 months), 222 of 736 patients (30.2 %) had AF recurrence. Of these 222 patients, 143 achieved clinical benefits and no further ablation was performed. No success or clinical benefit was achieved in 79 of 736 patients (10.7 %). Of these 79 patients, 53 patients chose rate control: 26/53 after 1 PVAI only, 24/53 after >1 PVAI but no additional substrate modification, and 3/53 after unsuccessful surgical MAZE. In the remaining 26 patients (3.5 %), multiple ablations (mean 2.7) with extensive substrate modification had been performed. These patients had mostly (longstanding) persistent AF (84.6 %), mean AF duration of 8.3 years and mean left atrial size of 48 mm. Conclusion: After single or repeated catheter ablations, 10.7 % of patients do not show success or clinical benefit. In most of these patients, rate control was chosen over repeated or extensive ablation. Eventually, catheter ablation truly failed in only 3.5 %. These patients had mostly (longstanding) persistent AF and an increased left atrial size.

12–3 Abstract 18–28

69 MECHANISMS OF ATRIAL ARRHYTHMIAS AFTER MAZE PROCEDURE AND LONG-TERM OUTCOME AFTER CATHETER ABLATION

Andrea Tordini¹, Madhan Nellaiyappan¹, Thanh Tran¹, Sanders Chae¹, Michael Fradley¹, S. Serge Barold¹, Bengt Herweg¹

¹ University of South Florida, Tampa, FL, USA

Background: Although the MAZE procedure is considered a highly effective therapy for atrial fibrillation (AF), recurrent atrial arrhythmias (AA) after MAZE are common and can alter quality of life and long-term outcome. The purpose of this study was to evaluate the mechanisms of AA, the procedural results and outcome of catheter ablation in patients after MAZE. Methods: We have identified 27 patients who underwent electrophysiology studies and catheter ablation for sustained AA after MAZE between 2002 and 2013. A retrospective review of the medical records and procedural data was performed. Results: Patient age was 66 ± 10 years; 19 (70 %) were male (EF = 49 ± 14 %, left atrial diameter = 48 ± 6 mm). Sixteen patients (59 %) had open chest, 9 (41 %) a minimally invasive MAZE and 18 (67 %) had additional cardiac surgery. The time from MAZE to ablation was 2.8 ± 2.3 years. The presenting AA was AF in 10 patients (37 %), a more organized AA in 17 patients (63 %), and was sustained in 10 patients. The number of AA substrates targeted was 2.4 ± 0.9 per patient. Pulmonary vein re-isolation was performed in 16 patients (59 %), targeting gaps in the surgical lesion set, requiring 19 ± 21 RF applications per patient. Right-sided linear ablation was performed in 12 patients (cavo-triscuspid isthmus [n = 12], scar dependent AA [n = 8]). Left-sided linear ablation was performed in 14 patients (mitral isthmus [n = 9], roof [n = 3], septum [n = 2]). In addition, we ablated focal right AT in 4 patients, focal left AT in 6 patients, a posterior wall rotor in 1 patient, and AVNRT in 1 patient. At the end of the procedure, 16 patients (59 %) were non-inducible by atrial burst pacing. The procedure time was 255 ± 103 min, fluoroscopy time was 57 ± 46 min. Re-ablation was performed in 10 patients (37 %). During a follow-up of 2.6 ± 2.5 years, one patient developed recurrent persistent atrial flutter after 8 years of follow-up. However, 12 patients (44 %) continued to have non-sustained AA and nine patients (33 %) remained on antiarrhythmic therapy with Dofetilide (n = 8) or Sotalol (n = 1). Three patients with refractory AA underwent AV junctional ablation. Conclusion: Patients with recurrent AA after Maze frequently have advanced atrial remodeling. Ablative therapy requires a step-wise approach, often targeting multiple different AA substrates. Re-isolation of the pulmonary veins was required in more than half of the patients. Scar-dependent right and left atrial flutters are frequently encountered. Aggressive ablative therapy leads to acceptable long-term results. However, adjunctive anti-arrhythmic therapy is needed in a third of patients.

12–4 Abstract 18–14

70 IMPACT OF CONTACT FORCE TECHNOLOGY ON ATRIAL FIBRILLATION ABLATION: A META-ANALYSIS

Mohammed Shurrab¹, Luigi Di Biase², David Briceno², Anna Kaoutskaia¹, David Newman¹, Ilan Lashevsky¹, Hiroshi Nakagawa³, Eugene Crystal¹

¹ Sunnybrook Health Sciences Centre, Toronto, Canada; ² Texas Cardiac Arrhythmia Institute, Austin, TX, US; ³ University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA

Background: Catheter–tissue contact is essential for effective lesion formation; hence, there is a growing usage of contact force (CF) technology in atrial fibrillation (AF) ablation. Data regarding the efficacy and safety of CF for catheter ablation of AF are limited. We conducted a meta-analysis to assess the impact of CF on clinical outcomes and procedural parameters in comparison to conventional catheter (CC) for AF ablation. Methods: An electronic search was performed using Cochrane central database, PubMed, Embase, and Web of Knowledge. References were searched manually. Outcomes of interest were as follows: recurrence rate, major complications (including major bleeding, ischemic stroke, embolism, or transient ischemic attack), total procedure, and fluoroscopic times. Continuous variables were reported as standardized difference in means (SDM); odds ratios (OR) were reported for dichotomous variables. Results: Eight studies (two randomized controlled studies and six cohorts) involving 530 adult patients (mean age 60 ± 2.3 years; 453 patients (85 %) with paroxysmal AF) were identified. CF was deployed in 203 patients. The range of CF used was between 5 and 40 g-force. Follow-up period ranged between 10 and 53 weeks. In comparison between CF and CC groups, a lower recurrence rate was noted with CF (19 vs. 33 %, OR 0.48 (95 % confidence interval [CI] 0.28; 0.79), P = 0.004). No significant heterogeneity was noted for the comparison (I ² = 8 %, P = 0.37). Shorter procedure but similar fluoroscopic times were achieved with CF (132 vs. 154 min, SDM −0.89 (95 % CI −1.74; −0.05), P = 0.04; 35 vs. 40 min, SDM −1.13 (95 % CI −2.51; 0.25), P = 0.11, respectively). Major complication rate was higher numerically in the CF group but this did not reach statistical significance (1.7 vs. 0.7 %, OR 1.98 (95 % CI 0.37; 10.59), P = 0.42). Conclusion: The use of CF technology results in a significant reduction of AF recurrence rate after AF ablation in comparison to CC group. CF technology is able to significantly reduce procedure time without compromising complication rate.

12–5 Abstract 14–11

71 ANTIARRHYTHMIC THERAPY POST-ABLATION TO REDUCE ATRIAL FIBRILLATION RECURRENCE: A META-ANALYSIS

Gustavo Goldenberg¹, Daniel Burd¹, Piotr Lodzinski², Giussepe Stabile³, Jacob Udell⁴, Mohammed Shurrab¹, Eugene Crystal¹

¹ Sunnybrook Hospital, Toronto, Ontario, Canada; ² Medical University of Warsaw, Department of Cardiology, Warsaw, Poland; ³ Laboratorio di Elettrofisiologia, Casa di Cura San Michele, Maddaloni, Italy; ⁴ Toronto General Hospital, Toronto, Ontario, Canada

INTRODUCTION: Three months of empirical antiarrhythmic drug (AAD) therapy after atrial fibrillation ablation (AFA) is common to prevent early AF recurrence with limited data to support this practice. OBJECTIVE: The study aims to perform a meta-analysis of published controlled trials comparing temporary AAD therapy after AFA with standard care in patients after AFA. The primary outcome was recurrence of arrhythmia. A subgroup analysis stratified patients by durations of follow-up at 6 months. RESULTS: Seven trials were included; six were randomized and one was a retrospective controlled study. Among 1245 patients, 763 (61.3 %) had paroxysmal AF, and 318 (25.5 %) had persistent AF. In total, 747 patients were treated with AADs and 498 patients served as a control group (no AA therapy). Various class IC-III antiarrhythmics were used. Length of AAD administration varied between 6 weeks immediately following AFA to 3 months. The follow-up duration ranged from 1.5 to 12 months. Among AAD-treated patients, the recurrence of arrhythmia rate was 33.4 vs. 39.5 % in control patients (odd ratio 0.75, 95 % CI 0.54–1.03, P = 0.08)., Subgroup analysis revealed that among patients followed for 6 months or longer after AFA, AAD-treated patients had an arrhythmia recurrence rate of 32.9 % compared with 45.1 % among control (odds ratio 0.55, 95 % CI 0.33–0.91, P = 0.02). However, no significant heterogeneity was noted compared with patients followed for less than 6 months (I ² = 39 %, P = 0.18). CONCLUSION: Antiarrhythmic therapy may help to reduce delayed (6 months or longer) recurrence of AF after AFA. A definitive large randomized controlled trial appears warranted to confirm these findings.

12–6 Abstract 18–12

72 ACUTE PROCEDURAL RESULTS AND MID-TERM OUTCOME OF ELECTROANATOMICAL GUIDED PULMONARY VEIN ISOLATION: A SINGLE CENTREOBSERVATIONAL STUDY COMPARING A REAL-TIME CONTACT FORCE SENSING VERSUS STANDARD TIP IRRIGATED ABLATION CATHETER

Daniele Muser¹, Luca Rebellato¹, Gaetano Nucifora¹, Domenico Facchin¹, Mauro Toniolo¹, Silvia Magnani², Alessandro Proclemer¹

¹ Azienda Ospedaliera Santa Maria della Misericordia di Udine, Udine, Italy; ² Azienda Ospedaliera di Trieste, Trieste, Italy

Aims: The additional benefit of real-time contact force (CF) measurement during pulmonary vein isolation (PVI) to improve procedural parameters and clinical outcome is unclear. We prospectively assessed the impact of real-time CF measurement on acute procedural parameters, procedural-related complications and mid-term outcome. Methods and results: One hundred consecutive patients (73 males) with paroxysmal (78) or persistent (22) atrial fibrillation (AF) who underwent PVI with CARTO® 3 electro-anatomical mapping (EAM) system (Biosense Webster Inc.) were consecutively assigned to either radiofrequency (RF) ablation using the 3.5-mm open irrigated Navistar®Thermocool®catheter (50 patients, standard group) or the new SmartTouchTM catheter with CF measurement capabilities (50 patients, CF group). PVI end point was set as validation of entry and exit block. Acute procedural parameters were assessed as well as mid-term follow-up. Baseline demographic, cardiovascular and anatomical characteristics were similar in both groups. Procedural data showed no significant differences in RF ablation time and in overall procedure duration. Significant reduction in fluoroscopy time (57 ± 16 vs. 29 ± 16 min) and a trend in reduction of procedural-related complications (10 vs. 2 %) were reported inCF group patients. No differences in mid-term risk of AF recurrence were observed between the two groups (8 % in the CF group vs. 10 % in the standard group at 12 months, respectively, log rank test p = 0.376). However, in CF group, patients with higher (>13.5 g) mean time-weighed CF resulted in a lower risk of 12-month follow-up AF recurrence (18 vs. 0 %; p = 0.041). Conclusion: The use of CF sensing technology in PVI reduces significantly fluoroscopy time and improves procedural safety. Patients with optimized contact force, presented lower risk of AF recurrences.

Poster session A part 1: Supraventricular arrhythmias: advances in mechanisms and management

Sunday, April 19, 2015

Posters exposed from 8:30 AM to 12:00 PM

Presenters and chairpersons present from 09:00 AM to 10:30 AM

13–1 Abstract 14–19

73 IVABRADINE VERSUS BISOPROLOL FOR INAPPROPRIATE SINUS TACHYCARDIA

Annamaria Martino¹, Antonella Sette¹, Marco Rebecchi¹, Ermenegildo de Ruvo¹, Luigi Sciarra¹, Lucia De Luca¹, Alessio Borrelli¹, Alessandro Fagagnini¹, Antonio Scarà¹, Leonardo Calo’¹

¹ Cardiology Department, Policlinic Casilino, Rome, Italy

Background: Inappropriate sinus tachycardia (IST) is commonly treated with beta-blockers. Ivabradine has been recently proved effective in IST. The aim of our study was to compare ivabradine and bisoprolol in the treatment of IST. Methods: Consecutive IST patients (pts) underwent an Holter ECG monitoring and a stress test. Thereafter, they were randomized to treatment with ivabradine or bisoprolol, started at an initial dosage of 5 mg bid or 1.25 mg/day, respectively. After 3 months of pharmacological treatment, all pts underwent an Holter ECG and a stress test. Results: Overall, 24 IST pts (mean age 34 ± 12 years; 23 women), all complaining of palpitations and stress intolerance, were administered ivabradine or bisoprolol (12 pts for each group). Baseline Holter ECG and stress test parameters were comparable in the two groups. The mean doses of ivabradine and bisoprolol administered were 5 ± 1.3 mg bid and 2 ± 1 mg/day, respectively. Mean Holter ECG HR lowered from 92 ± 4.3 to 76 ± 8 bpm with ivabradine (P < 0.001) and from 91 ± 5 to 81 ± 12 bpm with bisoprolol (P = 0.006, bisoprolol vs baseline; P = 0.02 ivabradine vs bisoprolol) after 3 months. Ivabradine, but non-bisoprolol, improved maximal Holter ECG HR (from 152 ± 16.6 to 128 ± 18 bpm; P < 0.001) and maximal HR at stress test (from 154 ± 12.5 bpm to 146 ± 15.5 bpm; P = 0.044). Minimal Holter ECG HR also lowered from 58 ± 9.5 to 52 ± 9 bpm with ivabradine (P = 0.039). An increase of at least 50 W in the maximal step at the stress test was observed in 41.7 and 50 % of ivabradine- and bisoprolol-treated pts, respectively. Complete resolution of IST-related symptoms occurred in the 89.5 and 75 % of cases with ivabradine and bisoprolol, respectively. Phosphenes occurred in 5.3 % of pts with ivabradine, whilst bisoprolol caused hypotension in 25 % of cases. Conclusions. In our population of pts affected by IST, 3-month treatment of ivabradine caused a stronger attenuation of mean and maximal Holter ECG HR and of maximal HR at stress test in comparison to bisoprolol. Ivabradine was also more effective in controlling symptoms and was better tolerated than bisoprolol.

13–2 Abstract 28–15

74 NONINVASIVE ELECTROCARDIOGRAPHIC IMAGING OF ATRIAL FLUTTER IN HUMANS USING PHASE MAPPING

Amiran Revishvili¹, Dmitry Lebedev², Michail Chmelevsky², Alexander Kalinin³, Vitaly Kalinin¹, Evgenii Labartkava¹, Oleg Sopov¹, Stepan Zubarev²

¹ Bakoulev Scientific Center for Cardiovascular Surgery, Moscow, Russia; ² Almazov Federal Heart, Blood and Endocrinology Centre, St. Petersburg, Russia; ³ Lomonosov Moscow State University, Moscow, Russia

Introduction. Noninvasive electrocardiographic imaging (ECGi) is a state-of-the-art electrophysiology methodology that has been used to reconstruct local unipolar electrograms at the epicardium from the body-surface potentials. We have extended ECGi to map both endo and epicardium. Here, we introduce phase mapping to analyze stable reentrant atrial flutter. The stability of flutter allowed us to validate ECGi with invasive electroanatomic mapping. Methods and results. Nine consecutive patients with type I atrial flutter (AFl) were examined. All patients underwent ECGi using an Amycard 01 C system (Amycard, Moscow, Russia). Data processing included reconstruction of unipolar electrograms, phase and isochronal mapping. Validation of the methodology was carried out based on electroanatomical mapping using a CARTO XP EP Navigation system (Biosense Webster, Diamond Bar, USA). Using isochronal maps of the right atrium, we conducted radio-frequency ablation of cavo-tricuspid isthmus in all patients. We visualized the spread of excitation using noninvasive phase mapping. A typical counterclockwise reentry circuit around the tricuspid valve with a transition through the cavo-tricuspid isthmus was the mechanism of AFl. We visualized two types of patterns of atrial activation which are typical for type I (N = 8) and lower-loop (N = 1) AFl. The results were confirmed using a CARTO XP system in all patients. Catheter ablation of the isthmus resulted in successful termination of AFl in all patients. Conclusions. Noninvasive phase mapping enables accurate detection of the activation pattern in type I AFl, which provides a powerful noninvasive tool for guiding catheter ablation.

13–3 Abstract 28–11

75 ABLATION OF ATYPICAL ATRIAL FLUTTERS USING ULTRA-HIGH-DENSITY ACTIVATION SEQUENCE MAPPING

Roger Winkle¹, Ryan Moskovitz², R. Hardwin Mead¹, Gregory Engel¹, Melissa Kong¹, William Fleming¹, Rob Patrawala¹

¹ Silicon Valley Cardiology, E Palo Alto, CA, USA; ² St. Jude Medical, St. Paul, MN, USA

Objectives: The study aims to evaluate ultra-high-density activation sequence mapping (UHD-ASM) for understanding and ablating atypical atrial flutters (AAFs) encountered during ablations. Methods: We examined 23 patients with 31 spontaneous/induced AAF. We created UHD-ASM during AAF using a 20-pole circular catheter and the EnSite Velocity System using the Precision Mapping Module. Results: The following are the patient demographics: age = 65.3 ± 8.5, male = 78 %, LA size = 4.66 ± 0.64 cm, hypertension = 60.8 %, paroxysmal AF = 21.7 %, and redo ablation in 20/23 (87 %). The AAF were LA in 30 (97 %) and RA in 1 (3 %). For each AAF, we mapped 3815 ± 2526 points and 1273 ± 697 points were used for UHD-ASM. The time to create and interpret the UHD-ASM was 20 ± 11 min. For every AAF, the entire circuit was identified. AAF was macroreentry in 30 (97 %) and microreentry in 1 (3 %). AAF cycle length was 267 ± 49 ms and the macroreentry circuit length was 138 ± 38 mm (range 35–187). Macroreentry flutters took varied pathways around the atria, but each had an area of slow conduction (ASC) averaging 16 ± 6 mm (range 6–29) in length. Conduction velocity for the rapid portion of the circuit was 0.70 ± 0.22 m/s and for the ASC was 0.21 ± 0.11 m/s. Entrainment was not utilized. We targeted the ASC (location roof = 5, typical mitral isthmus (MI) flutter (circuit exclusively around the valve) = 4, complex MI flutter using the perivalvular region extensively but also with non-mitral ASC = 11, LAA/LSPV ridge = 2, anteroseptal LA = 4, PVs = 2, posterior LA = 1, RA = 1). Ablation terminated AAF directly in 19/31 (61.3 %) and altered AAF activation in 7/31 (22.6 %) and the altered AAF terminated directly in all 7 with additional ablation and/or remapping. AAF degenerated to AF in 2/31 (6.5 %) with RF and could not be reinduced after ablation of the ASC. Thus, 28/31 (90.3 %) terminated with RF energy and/or could not be reinduced after ASC or micro reentry focus ablation. Median time from initial RF to AAF termination was 64 s. Eleven patients with complex MI flutter had the ASC away from the MI; ten were ablated successfully. Two of 4 patients with true complete MI flutter did not terminate with ASC ablation. All patients had pulmonary veins re-isolated when appropriate. Procedure time was 132 ± 32 min. There were no complications. Conclusions: Using only rapidly acquired UHD-ASM for AAF, the entire flutter circuit as well as a target ASC can be identified. Most AAFs were LA macroreentry. MI flutters were frequently complex and had the target ASC away from the MI. Ablation of the ASC or microreentry focus directly terminated or eliminated inducible AAF in 90.3 %.

13–4 Abstract 28–13

76 FEASIBILITY OF USING RIPPLE MAPPING IN A CONSECUTIVE SERIES OF ATRIAL TACHYCARDIA ABLATIONS

Vishal Luther¹, Shahnaz Jamil-Copley¹, Nicholas Linton¹, Michael Koa-Wing¹, Sajad Hayat¹, Norman Qureshi¹, Fu-Siong Ng¹, Belinda Sandler¹, Kevin Leong¹, Ian Wright¹, Zachary Whinnett¹, Phang Boon Lim¹, David Lefroy¹, David Wyn Davies¹, Nicholas Peters¹, Prapa Kanagaratnam¹

¹ Imperial College Healthcare NHS Trust, London, UK

Background: Ripple mapping (RM) is a novel clinical tool that displays electrograms at their corresponding 3D coordinate as a dynamic bar extending from a surface bipolar voltage map that changes in height according to the electrogram voltage-time relationship, gated to a fiduciary time point that enables mapping without point annotation or window-of-interest adjustments. We prospectively tested the RM module on CARTO3 v4 in a consecutive series of atrial tachycardia (AT) ablations. Methods: 3D maps were collected with CARTO3 v4 with color and fill threshold reduced to 5 mm to ensure dense and even point collection. RM preferences were set to clip bars at 0.25 mV and exclude points <0.03 mV. During RM playback, the bipolar voltage threshold was modified to display scar as areas devoid of ripple activation. Results: Nine patients (mean age 66 years, six male) were studied. The mean number of points collected was 837 (range 182–2426) over a mean chamber area of 205 ± 36 cm² (seven left atrium) and mapping time of 35 ± 8mins. Five maps were collected with ConfiDense automated mapping. RM demonstrated a focal origin in four patients and ablation at the earliest ripple bar terminated all cases. Macro-re-entry was demonstrated in the remaining five patients (see figure). Dual-loop re-entry involving the roof and mitral annulus was evident in three patients. Modifying the voltage threshold identified isthmuses of conduction bounded by islands of scar or previous ablation lines critical to these circuits. Ablation transecting these isthmuses changed or terminated tachycardia in each case. Automated isochronal maps were un-interpretable in two focal cases owing to inappropriate setting of the window of interest and four re-entrant studies due to the complexity of propagation. Conclusion: In this small series of prospective AT ablations, RM correctly defined the mechanism of AT and critical sites for ablation delivery.

13–5 Abstract 18–31

77 USE OF ELECTRICAL COUPLING INDEX IN TYPICAL ATRIAL FLUTTER ABLATION

Massimiliano Maines¹, Domenico Catanzariti¹, Carlo Angheben¹, Maurizio Del Greco¹

¹ Santa Maria del Carmine Hospital, Rovereto, Italy

Introduction. A new generation ablation system with an irrigated ablation catheter in conjunction with an advanced electro-anatomic mapping and navigation system allows the evaluation of the electrical coupling index (ECI), an indication of tip-to-tissue contact. The aim of our study was to evaluate if this index could also give an indication about ablation lesion efficacy. Methods. In patients undergoing typical right atrial flutter ablation, we compared the values of the ECI before, during (at the plateau) and after isthmus ablation. Permanent tissue damage or ablation lesion efficacy was defined as the reduction in the local potential >90 % or as potential split in two separate signals. In the absence of these endpoints, lesions were deemed ineffective. Results. Fifteen consecutive patients (11 males, age 69.3 ± 11.4 years) with history of typical atrial flutter underwent an ablation with Contact™ Therapy™ Cool Path™ Cardiac Ablation System in conjunction with EnSite™ Velocity Contact™ technology between Sep 2012 and Aug 2013. The target site for ablation was the isthmus between the inferior vena cava and the tricuspid valve. All the procedures were successful, without complications. The number of radiofrequency (RF) applications was 10.8 ± 6.7 (range 6–28) and RF time was 330.3 ± 177.5 s. ECI values are reported in the table:

	Overall	RF effective shots	RF ineffective shots	p*
RF duration (s)	31.7 ± 3.7	31.4 ± 3.9	36.1 ± 4.5	0.02
ECI pre ablation	100.1 ± 10.5	101.6 ± 10.8	104.8 ± 19.3	ns
Min ECI during RF (plateau)	56.3 ± 9.6	55.8 ± 9.7	68 ± 20.1	ns
ECI post ablation	81.0 ± 9.6	79.6 ± 10.9	95.4 ± 16.9	0.03
Delta ECI (pre-post ablation)	19.1 ± 5	22 ± 3.6	9.4 ± 2.5	<0.001
Delta% ECI (pre-post ablation)	18.5 ± 4.2	21.0 ± 3.6	8.8 ± 1.2	<0.001

RF effective applications needed less time and the ECI post-ablation was inferior compared to ineffective RF applications. The absolute and percentage ECI variations (pre-post ablation) were significantly greater when applications were effective (p < 0.001). From our data, it is possible to determine a 13 % cutoff value in the ECI variation that could be considered as the target for an effective ablation. Conclusion: The electrical coupling index can be used as a marker of ablation lesion efficacy in the ablation of typical right atrial flutter.

13–6 Abstract 14–17

78 INTERVENTIONAL TREATMENT SUPRAVENTRICULAR TACHYARRHYTHMIAS IN CHILDREN WITH CONGENITAL HEART DISEASE

Elena Artyukhina¹, Amiran Revishvili¹

¹ Bakulev Scientific Center for Cardiovascular Surgery, Moscow, Russia

Purpose: The study aims to evaluate the results of ablation of supraventricular tachyarrhythmia (SVT) in pediatric patients with congenital heart disease (CHD). Material and methods: From 2000 to 2014, electrophysiological study and catheter radiofrequency ablation for atrial tachyarrhythmias was performed in 215 children with congenital heart disease from 1 to 18 years. The median age was 10 ± 4.8 years (132 boys and 83 girls). Patients performed surgery on the following congenital heart disease: ASD, VSD, tetralogy of Fallot, Ebstein anomaly (in some cases—operation Sealy), transposition of great vessels and Fontan operation. Results: One hundred and thirteen patients had typical or atypical atrial flutter—all—in the postoperative period. Other arrhythmias were as follows: WPW syndrome 65 patients, AVNRT 18, ectopic atrial tachycardia 17 children, occurrence in preoperative (51 %) and in the postoperative period (49 %). The overall effectiveness of catheter ablation after repeated treatments was 87.2 %. Repeat procedures were performed totally in 10 % of patients and 5 % of them after Ebstein anomaly correction. Conclusion: the effectiveness of interventional treatment SVT in child with CHD in all cases depends on the age of the child, such as congenital heart disease and methods of surgical correction of congenital heart disease.

13–7 Abstract 08–12

79 CLINICAL IMPLICATION OF UNIPOLAR RECORDING FOR THE SLOW PATHWAY MAPPING IN PATIENT WITH TYPICAL AV NODE RE-ENTRY TACHYCARDIA AND PROLONGED PR INTERVAL

Andrey Ardashev¹, Evgeny Zhelyakov¹

¹ Federal Scientific and Clinical Centre, Moscow, Russia

Case report: We describe the case of a 71-year-old female with slow-fast atrioventricular (AV) nodal reentrant tachycardia (AVNRT) who had prolonged PR interval (260 ms) during sinus rhythm. Diagnosis was verified during electrophysiological study. At the beginning of the procedure, AH and HV intervals were 174 and 48 ms, respectively. Ablation targeting site was determined at the superior edge of the CS ostium guided by bipolar and unipolar recording. Slow pathway potential characterized by atrial component of the bipolar EG had qRs-like morphology, and the A/V ratio was 1.0. The unipolar targeting potential showed dual-component atrial EG, where the first component was a positive delta-like wave, which corresponded to isoelectric phase preceding qRsr′-like configuration on a bipolar EG. The second rS/RS component of unipolar EG had a sharp and biphasic morphology and corresponded to so-called R wave on a bipolar atrial EG (fig). RF-application at this site with target temperature of 55 C and power output 45 W resulted in appearance of accelerated junctional rhythm without VA conduction block. Following the elimination of the slow pathway, the PR and atrio-His intervals became shortened from 260 to 174 to 200 and 100 ms, respectively. The slow pathway RF-modification improved conduction of the proximal AV nodal structures and resulted in decreasing of the PR and atrio-His intervals. Moreover, the improvement of AV conduction after the slow pathway ablation lasted for at least 18 months. Conclusion: The main clinical implication of unipolar and bipolar recording for the AV slow pathway mapping and ablation in patients with prolonged PR concludes that this approach can allow treating AVNRT avoiding AV conduction impairment

13–8 Abstract 01–10

80 ADENOSINE SENSITIVITY OF RETROGRADE FAST PATHWAY CONDUCTION IN PATIENTS WITH SLOW-FAST ATRIOVENTRICULAR NODAL REENTRANT TACHYCARDIA: A PROSPECTIVE STUDY

Elena Efimova¹, Sam Riahi², Yan Huo¹, Andreas Bollmann¹, Masahiro Esato³, Thomas Gaspar¹, Philipp Sommer¹, Christopher Piorkowski¹, Gerhard Hindricks¹, Arash Arya¹

¹ Heart Center University Leipzig, Leipzig, Germany; ² Center for Cardiovascular Research, Aalborg Hospital, Aarhus University, Aalborg, Denmark; ³ Division of Cardiovascular Medicine, Yamaguchi University School of Medicine, Ube, Yamaguchi, Japan

Background: It is suggested that adenosine resistance of retrograde fast pathway in slow–fast atrioventricular nodal reentrant tachycardia (AVNRT) confirms the participation of a concealed retrograde atriohisian pathway, rather than a conventional fast pathway in the arrhythmia circuit of slow-fast AVNRT. Methods: Electrophysiologic parameters and adenosine sensitivity of the retrograde fast pathway were studied in 21 consecutive patients (18 women; age 57 ± 10 years) with slow–fast AVNRT and in a control group of 24 patients (11 women; age 46 ± 16 years) without documented supraventricular tachycardia in which AVNRT, accessory pathways, and other supraventricular tachycardias had been excluded. Results: Fifteen patients (71 %) with AVNRT and 18 patients (75 %) in the control group developed a transient VA block after intravenous administration of adenosine (P = 0.79). Among patients with slow–fast AVNRT, female gender (P = 0.003), longer VA interval during right ventricular pacing (P < 0.001), and longer tachycardia’s cycle length (P < 0.001), but not age (P = 0.87), HA and VA intervals during tachycardia (P = 0.82 and P = 0.99) and ventricular pacing (P = 0.85) predicted transient VA block after intravenous administration of adenosine. Among patients in the control group, a shorter VA interval during fixed rate right ventricular apical pacing (P = 0.009) and the presence of dual AV nodal physiology (P = 0.002) were associated with adenosine resistance of the retrograde fast pathway. Conclusion: The prevalence of adenosine resistance of the retrograde fast pathway’s conduction is comparable between patients with and without slow–fast AVNRT. This finding can be better explained by the existence of an insulated intranodal tract with Purkinje-like properties or a superior atrionodal connection to the nodo-hisian region of the AV node, rather than presence of an atriohisian pathway.

13–9 Abstract 13–10

81 EXTRACORPORAL MEMBRANE OXYGENATION SUPPORT FOR LIFE-THREATENING ATRIOVENTRICULAR REENTRY TACHYCARDIA IN A NEWBORN

Fridrike Stute¹, Florian Arndt¹, Urda Gottschallk¹, Boris Hoffmann², Thomas S. Mir¹, Goetz C. Mueller¹, Christian Thiel¹, Rainer Kozlik-Feldmann¹

¹ Department of pediatric Cardiology, Hamburg, Germany; ² University Heart Center, Hamburg, Germany

Life-threatening atrioventricular reentry tachycardia in newborn is a rare disease. We report the case of a 16-day-old newborn submitted in cardiogenic shock requiring cardio pulmonary resuscitation (CPR) and extracorporeal membrane oxygenation (ECMO). The patient was presented with a history of occasional vomiting over the past 6 days and an accelerated heart beat was noticed the evening before admission by the parents. At the time of admission, the child showed clinical signs of severe cardiac failure and an atrioventricular reentry tachycardia with a heart rate of 240 bpm and a left bundle brunch block. Echocardiography showed highly reduced left ventricular function and a massive dilatation of the left ventricle. Therapy with adenosine and amiodarone led to conversion to sinus rhythm detecting an antidromic leading accessory pathway conduction but was not sufficient to restore a permanent stable circulation. Regarding a continuous need of CPR, a venous-arterial ECMO must be established leading to resumption of proper organ functions. Therapy with intravenous amiodarone and flecainide led up to control of frequency and increasingly normal cardiac rhythm and the extracorporeal circulatory support could be explanted after 4 days. The initiation of propafenone and medical cardioversion with adenosine restored permanent sinus rhythm after 6 days. Two recurrences of tachycardia could be controlled with propafenone, metoprolol and adenosine boluses. The child was discharged from hospital at day 25 in sinus rhythm and completely restored left ventricular function. This case report demonstrates the rapid deterioration of a seemingly healthy newborn as the consequence of previously undiagnosed accessory pathway conduction. Maximal technical and pharmacological efforts were needed to treat severe cardiac failure until coordinated rhythm was restored but complete restitution of cardiac function could be achieved at last.

13–10 Abstract 14–15

82 OUR EXPERIENCE OF RADIOFREQUENCY ABLATION OF ISTHMUS DEPENDENT ATRIAL FLUTTER IN EARLY POSTOPERATIVE PERIOD AFTER OPEN HEART SURGERY

Roman Marchenko¹, Sergey Durmanov¹, Natalia Makarova¹, Alexander Kozlov¹, Vladlen Bazilev¹

¹ Federal Center of Cardiovascular Surgery, Penza, Russia

Isthmus-dependent atrial flutter (IDAF) is the most common atrial arrhythmia occurring in early postoperative period after open heart surgery. There are no current guidelines for management and no data regarding effectiveness of radiofrequency ablation (RFA) in this cohort of patients. Purpose: The study aims to assess the effectiveness of RFA of IDAF in early postoperative period after open heart surgery. Materials and methods: During the period of time from January 2012 to November 2013, 185 patients with IDAF were undergone RFA procedure in our hospital and included into study. Mean age of patients was 58.4 ± 8.4 years, 142 males (76.8 %). The first group included 14 patients with IDAF appeared in early postoperative period after open heart surgery with cardiopulmonary bypass due to CAD, congenital or acquired valvular heart disease. IDAF appeared on 2–9 days (mean 5.3 ± 2.4). RFA of IDAF was performed on 6–18 days after surgery (mean 10.4 ± 3.3). The second group included 20 patents with IDAF and history of open heart surgery 4–606 months ago. The third group (control) included 151 patients with IDAF with no history of open heart surgery. Results. Effectiveness of RFA of IDAF was evaluated by assessment of bidirectional block of conduction through the isthmus, duration of procedure and fluoroscopy time. Criteria of conduction block were achieved in 174 out of 185 patients. Effectiveness of procedure was 94.1 % and did not differ among the groups. Mean procedure duration was 73.3 ± 33.6 min. Significant differences of procedure duration were revealed between the second and thirrd groups (p = 0.004). Mean fluoroscopy time was 717.7 ± 453.5 s. Fluoroscopy time differed in the second and third groups (p = 0.004). All procedures were performed without complications. Conclusion. RFA of IDAF can be effectively performed shortly after open heart surgical operation.

13–11 Abstract 18–17

83 A NEW METHOD TO DETERMINE BIDIRECTIONAL BLOCK OF THE CAVOTRICUSPID ISTHMUS

Concepcion Alonso-Martin¹, Enrique Rodriguez-Font¹, Jose Guerra¹, Francisco Mendez¹, Marcos Rodriguez¹, Douglas Alvarez¹, Pelayo Torner¹, Xavier Viñolas¹

¹ Hospital de Sant Pau, Barcelona, Spain

Introduction. Bidirectional conduction block through the cavotricuspid isthmus is the main goal of typical atrial flutter (AFL) ablation. Assessment of conduction block requires mapping of activation at both sides of the ablation line during pacing from the proximal coronary sinus and lateral right atrium. Several methods have been proposed to assess isthmus block. However, they do not explore the line itself and require a high number of catheters. We sought to describe a simple pacing maneuver to assess conduction block at the ablation line during pacing from the ablation catheter. Methods. Patients underwent a typical AFL ablation were included. Multipolar catheters were positioned inside the coronary sinus and at the His region. Once isthmus block was achieved, the ablation catheter was positioned along the ablation line, where double potentials were recorded. Pacing was performed from the distal and proximal bipoles in an attempt to capture only one of the double potentials and record the other one. Conduction time from the pacing artifact to the second potential was measured. The results were validated with classical pacing maneuvers. Results. Forty patients (age 65 ± 12, 90 % male) were included. The maneuver was successfully performed in 37/40 (92.5 %). A positive maneuver from lateral to septal was obtained in 30/40 (75 %) patients, from septal to lateral in 18/40 (45 %) and in both directions in 15/40 (38 %). Mean conduction time during the pacing maneuver was longer than with classical maneuvers: 183 ± 25 ms when pacing lateral to septal versus 144 ± 32 ms during pacing from the lateral right atrium and 182 ± 23 ms when pacing septal to lateral versus 142 ± 31 ms during pacing form the proximal coronary sinus. Conclusion. The presented pacing maneuver allows ensuring isthmus block from the isthmus line itself with fewer numbers of catheters.

13–12 Abstract 18–34

84 BENEFICIAL USE OF A DUODECAPOLAR CATHETER FOR MAPPING AND ABLATION OF RIGHT FREE WALL ACCESSORY PATHWAYS.

Yoav Michowitz¹, Aharon Glick¹, Bernard Belhassen¹

¹ Cardiac Electrophysiology Laboratory, Department of Cardiology, Tel-Aviv Sourasky Medical Center., Tel-Aviv, Israel

Background: Ablation of right free wall accessory pathways (RFWAP) is sometimes difficult due to the catheter instability at the tricuspid valve annulus (TVA) and the lack of anatomic guidance such the coronary sinus for left APs. Methods: For the last 4 years, we have systematically used a duodecapolar (DD) mapping catheter (St Jude) in which the proximal ten electrodes are in close contact with the TVA with the hope it will facilitate mapping and ablation of RFWAP located at the TVA. Results: Eight consecutive patients (four M, four F, aged 19–34 years), suffering from palpitations (suspected SVT) in the presence of manifest WPW (n = 4 pts) and LBBB-tachycardias mediated by a Mahaim fiber (n = 3) as well as one asymptomatic WPW patient were included. Three patients had undergone prior ablation procedures. With the DD catheter deployed at the TVA, the AP location was rapidly identified as follows: (a) in patients with AVRT using the sites of earliest ventricular activation in sinus rhythm, or earliest atrial activation during AVRT or ventricular pacing (5/5 patients); (b) in patients with atriofascicular Mahaim fiber by the recording of a “Mahaim potential” in sinus rhythm (2/3 patients). In all these seven patients, APs were ablated after positioning the ablation catheter close to these areas. In one patient with Mahaim, the AP was ablated empirically. Successful ablation was achieved with one RF pulse (five patients), three RF (two patients), and nine RF (one patient). AP locations were: anterior (n = 1), lateral (n = 2), antero-lateral (n = 1), postero-lateral (n = 3), and posterior (n = 1). One patient with AVRT required an additional procedure. All patients have remained free-symptoms with no AP recurrence after a mean follow-up of 19 ± 18 months. Conclusion: A DD catheter positioned at the TVA facilitates fast localization of RFWAP and guides their successful ablation.

13–13 Abstract 20–11

85 MEDIUM- AND LONG-TERM SIDE EFFECTS OF AMIODARONE “AMIOTOX STUDY”

Marouane Mahjoub¹, Mejdi Ben Messaoud¹, Majed Hassine¹, Wiem Selmi¹, Zohra Dridi¹, Fethi Betbout¹, Habib Gamra¹

¹ Cardiology Department A: Fattouma Bourguiba University Hospital, Monastir, Tunisie

Background: Amiodarone is a widely used antiarrhythmic drug in Tunisia worldwide. However, its side effects are quite frequent hampering its use despite its efficacy. The purpose of our study was to determine the prevalence of amiodarone side effects and to analyze its predictors in our population. Methods: Amiotox registry is a multicenter cross-sectional study including patients receiving amiodarone for more than 6 months regardless of the indication. We sought to detect the frequency and predictors of amiodarone side effects in our population. Results: From 1st May 2010 to 30th April 2012, 200 consecutive patients (mean age 61, 9 ± 12, 9 years) were included. Mean duration of amiodarone therapy was 51.9 ± 48.4 months with a mean dose of 288.1 ± 274.2 g. Atrial fibrillation (81, 5 %) was the most common indication. Amiodarone side effects occurred in 144 patients (72 %): ocular (65.5 %), thyroid (47.5 %), cardiac (35 %), cutaneous (30.5 %), hepatic (16.5 %) and neurological (14.5 %) toxicity. No case of pulmonary toxicity was reported. Referring to multivariate analysis, independent predictors were as follows: advanced age (p = 0.02), treatment duration (p < 0.01) and cumulative dose (p < 0.01) for occurrence of all side effects; treatment duration sup 6 months (p = 0.008) for corneal deposits; age >70 years (p = 0.002) and treatment duration (p < 0.001) with a linear correlation for cutaneous toxicity; cumulative dose > 300 g (p = 0.016) and heart failure (p = 0.05) for bradycardia; cumulative dose >100 g (p = 0,012) for QT prolongation; treatment duration (p < 0, 001) with a linear correlation and betablockers concomitant use (p = 0.046) for PR elongation; treatment duration (p < 0, 001) with an exponential correlation and concomitant vitamin K anticoagulant use (p = 0.018) for hepatic toxicity; and treatment duration >18 months (p = 0.009) and concomitant calcium channel blocker use (p < 0.001) for neurological toxicity. Conclusion: The results of our study confirmed that amiodarone side effects are quite frequent in our population and that in addition to treatment dose and duration, other predictors for these effects were identified such as age and some drug associations. Clinicians may be able to use the present results to identify patients at higher risk for amiodarone toxicity and implement strategies to improve the monitoring of these effects.

13–14 Abstract 07–10

86 DYSRHYTHMIA IN PATIENTS WITH DIFFERENT TYPES OF ATRIAL SEPTAL DEFECTS: A COMPARISON OF INCIDENCES

Charlotte Houck¹, Christophe Teuwen¹, Rik Jansen¹, Karin Kraaier², Jurren van Opstal², Joris Vriend³, Pepijn van der Voort⁴, Thelma Konings⁵, Maarten Witsenburg¹, Jolien Roos-Hesselink¹, Ad Bogers¹, Natasja de Groot¹

¹ Erasmus Medical Center, Rotterdam, Netherlands; ² Medisch Spectrum Twente, Enschede, Netherlands; ³ Haga Hospital, The Hague, Netherlands; ⁴ Catharina Hospital, Eindhoven, Netherlands; ⁵ VU University Medical Center, Amsterdam, Netherlands

Background: Dysrhythmia are a common complication in patients with an atrial septal defect (ASD), often leading to morbidity and mortality. Many studies only examined the occurrence of atrial tachyarrhythmia, but little is known about the incidences of sinus node dysfunction (SND), ventricular tachyarrhythmia (VT) and atrioventricular blocks (AVB) in ASD patients. The aim of this study is to (1) determine incidences of dysrhythmia and AVB and their development over time in patients with five different types of ASD and (2) study the association between age at surgical ASD repair and development of dysrhythmia and AVB. Methods: We included adult patients (N = 285) with a primum ASD, secundum ASD, sinus venosus ASD, patent foramen ovale (PFO) or complete atrioventricular septal defect (cAVSD) who underwent either surgical, percutaneous or no ASD repair. Patients’ medical records were reviewed for the occurrence of SND, atrial and ventricular tachyarrhythmia and AVB. Results: Patients either had a primum ASD (n = 52), secundum ASD (N = 155), sinus venosus ASD (N = 24), PFO (N = 39) or a cAVSD (N = 15). These patients had undergone surgical (N = 178), percutaneous (N = 66) or no (N = 41) ASD repair. At 80 years of age, over 70 % of all ASD patients had presented with SND and over 50 % had experienced at least one episode of atrial tachycardia (AT). Furthermore, less than 10 % of all patients were free from atrial fibrillation (AF) after 80 years. The cumulative incidence of VT remained relatively low (15 to 20 % after 80 years). AVBs were commonly observed in all ASD patients (65 % after 80 years) but they developed significantly earlier and more often in patients with a primum ASD or cAVSD. Patients who were younger than 25 years at the time of surgical ASD repair developed SND, AT and AVB 20 to 50 years earlier compared to patients who were older than 25 years during ASD repair. Patients who were between 26 and 45 years during ASD closure developed SND, AF and AVB approximately 20 years earlier than patients who were older than 46 years during ASD repair. However, cumulative incidences of these dysrhythmia and AVB after 70 years were comparable. Conclusions: SND and atrial tachyarrhythmia were often observed in all patients, whereas AVBs were more prevalent in patients with a primum ASD or cAVSD. Age at the time of surgical ASD repair appeared to influence the development of dysrhythmia over time, whereas the cumulative incidences after 70 years were comparable between all age groups.

13–15 Abstract 07–11

87 DEVELOPMENT OF ATRIAL FIBRILLATION IN PATIENTS WITH CONGENITAL HEART DEFECTS

Christophe Teuwen¹, Tanwier Ramdjan¹, Ameeta Yaksh¹, Luca Jansz¹, Dominic Theuns¹, Sander Molhoek², Reinhart Dorman³, Jurren van Opstal³, Thelma Konings⁴, Joris Vriend⁵, Marco Götte⁵, Pepijn van der Voort⁶, Etienne Delacretaz⁷, John Triedman⁸, Natasja de Groot¹

¹ Erasmus Medical Centre, Rotterdam, Netherlands; Amphia Hospital, Breda, Netherlands; ³ Medisch Spectrum Twente, Enschede, Netherlands; ⁴ VU Unitversity Medical Centre, Amsterdam, Netherlands; ⁵ Haga Hospital, The Hague, Netherlands; ⁶ Catharina Hospital, Eindhoven, Netherlands; ⁷ Inselspital, University of Bern, Bern, Switzerland; ⁸ Children’s Hospital and the Department of Pediatrics, Harvard Medical School, Boston, MA, USA

Background: Regular atrial tachycardia (AT) and atrial fibrillation (AF) occur frequently in patients with congenital heart defects (CHD). Whereas AT has extensively been studied, studies about AF in CHD patients are rare, despite the reported incidence of AF which ranges up to 30 %. The aim of this multicenter study was to examine the development of AF over time in a large cohort of patients with a variety of CHD by relating patient with arrhythmia characteristics. The time course of AF after the first episode and the outcome of AF therapy during long-term follow-up was additionally evaluated. Methods: Electrocardiograms (ECG) and 24-h Holter registrations were retrospectively reviewed for the presence of AF and regular AT. Patients were then classified according to the severity of CHD. Ventricular response was determined during the first episode of AF. Finally, deterioration of AF from paroxysm to long-standing persistent/permanent AF was reviewed. Results: In total, 193 CHD patients presented with a documented episode of AF at the age of 49 ± 17 years. Patients with a simple defect developed AF at an older age (N = 71, 59 ± 15 years, p < 0.001) compared to patients with a moderate (N = 88, 47 ± 14 years) or complex (N = 34, 36 ± 15 years) CHD. Ventricular response was 101 ± 31 bpm; patients with a moderate defect had a higher ventricular response than patients with complex CHD (107 ± 32 bpm versus 91 ± 30 bpm, p = 0.01). AF developed as ‘de novo’ in 160 patients, and regular AT preceded AF 5 ± 5 years in 33 patients. Subsequently, another 18 patients initially developed AF which was followed by regular AT 5 ± 5 years after the first episode. Of all the patients, 23 patients progressed from paroxysm AF to long-standing persistent/permanent AF 4 ± 4 years after the initial episode. Conclusion: AF occurs in all types of CHD and the age at which this occurs appears to depend on the complexity of the CHD. In this complex group, ventricular response is relatively low, which may indicate a reduced function of the atrioventricular node. In a considerable part of this patient group, AF co-existed with regular AT; regular AT preceded AF and vice versa. Furthermore, paroxysmal AF progressed relatively fast to long-standing persistent/permanent AF and, therefore, an aggressive therapy of both regular AT and AF is reasonable.

Poster session A part 2: Atrial fibrillation characteristics and management

Sunday, April 19, 2015

Posters exposed from 8:30:00 AM to 12:00 PM

Presenters and chairpersons present from 10:30AM to 12:00 PM

13–16 Abstract 20–10

88 THE EFFECT OF CRP REDUCTION WITH A HIGHLY SPECIFIC ANTISENSE OLIGONUCLEOTIDE ON PAROXYSMAL ATRIAL FIBRILLATION ASSESSED USING BEAT-TO-BEAT PACEMAKER HOLTER FOLLOW-UP

Conn Sugihara¹, Nick Freemantle², Steven Hughes³, Steve Furniss¹, Neil Sulke¹

¹ East Sussex Healthcare NHS Trust, Eastbourne, UK; ² University College London, London, UK; ³ ISIS Pharmaceuticals, Carlsbad, CA, USA

Background: Atrial fibrillation (AF) is well-recognised to have an inflammatory component. C-reactive protein (CRP) is known to be strongly associated with AF. However, it is not clear if CRP is a causal factor for AF. ISIS-CRPRx is a novel antisense oligonucleotide that reduces CRP production by specifically inhibiting mRNA translation. Methods: A double-blind phase II trial of ISIS-CRPRx in patients with paroxysmal AF and DDDRP permanent pacemakers (PPMs) with advanced atrial and ventricular Holters allowing beat to beat arrhythmia follow up. Results: Twenty-six patients were screened and seven patients dosed with ISIS-CRPRx. After 4 weeks of baseline assessment, patients were randomly assigned to two treatment periods of either placebo then ISIS-CRPRx or ISIS-CRPRx then placebo. All patients were followed up for 8 weeks after the active treatment period. There was a 63.7 % (95 % CI 38.4 % to 78.6 %, p = 0.003) relative reduction in CRP on treatment with ISIS-CRPRx versus baseline. Sensitivity analyses demonstrated a consistent treatment effect. The primary endpoint was change in AF burden assessed by PPM. There was no significant difference in AF burden on treatment with ISIS-CRPRx versus baseline (OR 1.6, 95 % CI −2.42 to 5.62, p = 0.37). ISIS CRPRx was safe and well tolerated and there were no serious adverse events. Conclusions: Treatment with ISIS-CRPRx did not reduce AF burden in patients with paroxysmal AF and PPMs, despite a large relative reduction in CRP. In this population, highly specific CRP reduction had no clinically discernable effect upon paroxysmal AF. CRP does not appear to have a causal relationship with AF.

13–17 Abstract 15–44

89 QUICK INFUSION VS REPEATED INTRAVENOUS BOLUSES OF FLECAINIDE FOR ATRIAL FIBRILLATION TERMINATION: A SINGLE-BLIND, TREATMENT REGIMEN CONTROLLED TRIAL.

Saverio Lavanga¹, Daniele Nassiacos¹

¹ Saronno Hospital-AO Busto Arsizio (VA), Pogliano Milanese, Italy

To assess the efficacy of a quick infusion of flecainide (fleca) vs repeated intravenous boluses of fleca in terminating, acute atrial fibrillation (AAF) within 20 min, 67 patients (pts) were randomized 33 to quick infusion and 34 to boluses. One patient assigned to boluses group was excluded for sinus rhythm restoration at the beginning of treatment. This study was approved by our ethical committee, began on February 20th, 2007, and was closed on December 31st, 2013. Method: In pts with AAF (<48-h duration), stable for at least 1 h, with a ventricular response rate (VRR) greater than 70 bpm and without signs of heart failure, acute myocardial infarction, arterial hypotension, clinically evident mitral stenosis, non-corrected myocardial ischaemia, electrolyte imbalances, significant hepatic or renal disease, acidosis, pulmonary embolism or pregnancy, we gave intravenously either 2.1 mg/kg of fleca in 15 min or 0.7 mg/kg boluses of the same drug, with a maximum of 50 mg per bolus, in 20–30 s every 3 min, until sinus rhythm (SR) was restored or the full dose of 2.1 mg/kg was reached. Each treatment was carried out during continuous 12 lead ECG recording, until SR restoration or to 20 min from the beginning of treatment. Cuff blood pressure was detected every 3 min. Results: Success rate for infusion group (I-GR) and for boluses group (B-GR) was as follows:

	1 bolus	2 boluses	3 boluses	Total	Percentage of success
I-GR	–	–	–	14/33	42
B-GR	8	7	10	25/33	76
P	–	–	–	<0.002	0.002

Mean time to SR restoration was 9.9 ± 4 for the I-GR vs 6.11 ± 4.4 min for the B-GR (p = 0.008). The electrical pause before SR was 1071 ± 381 ms in the I-GR vs 1350 ± 1150 ms in the B-GR (p = NS). The mean RR interval before treatment was 540 ± 114 in the I-GR vs 509 ± 102 ms in the B-GR (p = NS). The mean age was 65.8 ± 13 in the I-GR vs 64.4 ± 10.6 years in the B-GR (p = NS). Associated heart disease was, respectively, hypertensive in 11 and 11, valvular in 9 and 10, others in 1 and 3 and absent in 12 and 9 patients. Eighteen pts were males and 15 were females in the I-GR and 21 were males and 12 were females in the B-GR. Mean duration of arrhythmia before treatment was 13.6 ± 9.6 h in the I-GR vs 10.6 ± 8.2 h in the B-GR (p = NS). Conclusions: These data suggest that flecainide given in boluses is more effective and quicker than flecainide given in infusion in converting AAF to SR.

13–18 Abstract 21–11

90 ATRIAL FIBRILLATION “BURDEN” ON THERAPY IS RELATED TO OUTCOMES ON ANTIARRHYTHMIC DRUG THERAPY

Sanjeev Saksena¹, April Slee¹, Rangadham Nagarakanti¹, Marwan Saad¹

¹ Electrophysiology research Foundation, Warren, MI, USA

Introduction: The relationship between atrial fibrillation (AF) recurrences and major cardiovascular events is unclear. Methods: We quantitated electrocardiographic burden (“burden”) of recurrent AF in the rhythm control arm of the AFFIRM trial. We examined cardiovascular hospitalizations (CVH) and death (D), based on initial antiarrhythmic drug (AAD) selection. Amiodarone (Amio), sotalol (Sot) and class 1C (flecainide and propafenone) gps were compared to propensity score matched (PSM) rate gps for freedom from CVH or D. AF burden at follow-up visits was stratified as <25 or >25 % of all visits during follow-up. Results: 687 Amio patients, 581 Sot patients and 251 1C patients from the rhythm arm were matched 1:1 to PSM rate cohorts. They were comparable for baseline characteristics. CVH risk was significantly higher during follow-up when AF burden was >25 % compared to <25 % for all three AADs (Amio hazard ratio {HR} = 1.44, p = .001; Sot HR = 1.46, p = .0011; class 1C HR = 2.76, p < .0001) (Figure). Mortality for both AF strata for all three AADs was comparable to their matched rate gps. Conclusions: 1. While infrequent AF recurrence on AADs used in the AFFIRM trial did not increase risk for CVH or D compared to rate, > 25 % AF burden was associated with substantially increased CVH risk. 2. In AF patients on AADs, total mortality did not differ among the AF burden strata studied. 3. Quantitation of AF recurrences on AADs may be important in therapeutic decision making to avoid CVH and permit earlier institution of alternative rate or rhythm control

13–19 Abstract 09–10

91 SINUS NODE DYSFUNCTION IS ASSOCIATED WITH HIGHER LEFT ATRIAL PRESSURE DURING SINUS RHYTHM THAN ATRIAL FIBRILLATION IN PATIENTS WITH ATRIAL FIBRILLATION

Tae-Hoon Kim¹, Junbeom Park¹, Jin-Kyu Park¹, Jae-Sun Uhm¹, Boyoung Joung¹, Moon-Hyoung Lee¹, Hui-Nam Pak¹

¹ Yonsei University Health System, Seoul, Republic of Korea

Background: Although atrial fibrillation (AF) is commonly associated with sinus node dysfunction (SND), hemodynamic characteristics of those patients have not yet been investigated. Objective: The purpose of this study was to determine whether elevated LAP plays some role in the pathogenesis of SND among patients with AF. Methods: We included 182 patients (67.6 % male, 59.0 ± 11.1 years old, 69.2 % paroxysmal AF) who underwent radiofrequency catheter ablation for AF. We measured both LAPpeak(SR), LAPpeak(AF), and LA pulse pressure [LApp = LAPpeak(SR)-LAPnadir(SR)] at the beginning of the ablation procedure, and compared LAPs from 30 patients with SND (19 sick sinus syndrome, 11 tachycardia-bradycardia syndrome) and those from 152 patients without SND (control). Results: 1. Patients with SND were older (p = 0.040), more likely to be female (p = 0.007), and had a greater E/Em ratio (p = 0.042) than those without SND. 2. In the SND group, LAPpeak(SR) and LApp(SR) were significantly higher than LAPpeak(AF) (p = 0.005) and LPpp(AF) (p < 0.001), respectively. However, that was not the case in the Control group. 3. LAPpeak(SR-AF) (OR 1.08, 95 % CI 1.02∼1.14, p = 0.008) and Lapp (SR-AF) (OR 1.08, 95 % CI 1.02–1.15, p = 0.014) were independently associated with SND. 4. Pacing rate (90∼120 bpm)-dependent escalation of LAPpeak(pace) was significant in the control group (p < 0.001), but blunted in the SND group (p = 0.724) due to pre-elevated LAPpeak(pace) at low heart rate. Conclusions: In AF patients with SND, hemodynamic loading measured by LAPpeak and atrial stiffness estimated by LApp were significantly higher during SR than AF compared to AF patients without SND.

13–20 Abstract 15–22

92 ELECTRICAL CONNECTIONS BETWEEN IPSILATERAL PULMONARY VEINS MIGHT BE EASILY IDENTIFIED USING A SPECIFIC PACING MANEUVER

Concepcion Alonso-Martin¹, Jose Guerra¹, Enrique Rodriguez-Font¹, Marcos Rodriguez¹, Douglas Alvarez¹, Pelayo Torner¹, Francisco Mendez¹, Xavier Viñolas¹

¹ Hospital de Sant Pau, Barcelona, Spain

Introduction. Anatomical studies have shown muscular connection between ipsilateral pulmonary veins (PV) in more than 80 % of hearts. However, electrical connections have been rarely reported during electrophysiological studies. We sought to demonstrate electrical connections between ipsilateral PVs by using a pacing maneuver after circumferential ablation of the PVs. Methods. Consecutive patients who underwent a circumferential AF ablation procedure were included. After circumferential ablation and once entrance block was achieved, a pacing maneuver was performed. The circular catheter was positioned in one vein and the ablation catheter in the ipsilateral vein. During pacing from one of the ipsilateral veins, demonstration of synchronous local capture in both veins dissociated from the left atrium ensured the presence of electrical connection between the veins. Results. Twenty-nine consecutive patients (mean age 60 ± 8, 75 % males, 96 % Paroxysmal AF) were included. Electrical connections were demonstrated by using the pacing maneuver in 9/29 (31 %): 6 (28 %) had PV connections in the left PVs and 3 (22 %) in the right PVs. Conclusion: The presented pacing maneuver allowed demonstration of electrical connections in 31 % of our patients. This may have implications in defining the best ablation approach.

13–21 Abstract 15–21

93 CONSISTENCY OF QTC MEASUREMENTS IN ATRIAL FIBRILLATION PATIENTS BEFORE AND AFTER CARDIOVERSION

Vincent Jacquemet¹, Bruno Dubé², Omar Mahiddine², Alain Vinet¹, Aimé-Robert LeBlanc², Marcio Sturmer², Giuliano Becker², Teresa Kus², Réginald Nadeau²

¹ Université de Montréal, Montréal, Canada; ² Hôpital du Sacré-Coeur de Montréal, Montréal, Canada

Background: Measurement of QTc intervals during atrial arrhythmias is relevant to the safety of antiarrhythmic drug delivery. Atrial fibrillation (AF) waves may affect the T wave and hinder the identification of fiducial points, possibly resulting in inaccurate QT measurements. In addition, constant fluctuation in heart rate complicates the analysis. Aim: The study aims to compare QT and QTc intervals in AF patients before and after cardioversion. Methods: Twenty-one patients suffering from AF underwent electrical cardioversion. All were in AF at the time of the procedure. Cardioversion restored sinus rhythm in all patients. Pseudo-orthogonal Holter ECGs were continuously recorded during at least 1 h before and 1 h after the procedure. RR and QT time series were extracted and semi-automatically validated. For Q onset and T end identification, the lead with the most identifiable T wave was used. QTc intervals were computed using Bazett, Fridericia and patient-specific correction formulae, both with and without QT hysteresis correction with a time constant of 2 min (moving average of past RR values). Results: Both RR and QT intervals were prolonged after cardioversion (RR = 1048 ± 172 ms in sinus rhythm vs 691 ± 127 ms in AF; QT = 412 ± 23 vs 361 ± 26 ms). After correction for heart rate, the difference QTc(sinus rhythm)-QTc(AF) was −28 ± 20 ms (p < 0.001) with Bazett’s formula, thus indicating overcorrection, 0.2 ± 10.2 ms (p = 0.9) with Fridericia’s and −0.9 ± 5.1 ms (p = 0.4) with patient-specific correction. The root-mean-square difference between QTc (sinus rhythm) and QTc (AF) was 34 ms with Bazett’s formula, 10 ms with Fridericia’s and 5 ms with patient-specific correction. The variability of QTc over 1 h during AF was smaller with patient-specific correction (Bazett 51 ± 9 ms; Fridericia 34 ± 8 ms; patient-specific 20 ± 7 ms). QTc variability was significantly further reduced when hysteresis correction was applied (Bazett 22 ± 10 ms; Fridericia 20 ± 10 ms; patient-specific 17 ± 7 ms). Conclusion: QTc measurements during AF were consistent with values obtained after sinus rhythm was restored. Although patient-specific formula performance was better, Fridericia’s correction combined with hysteresis reduction was found to be sufficiently reliable for the assessment of the QTc in AF.

13–22 Abstract 15–20

94 MINIMIZING RADIATION EXPOSURE USING REMOTE MAGNETIC CATHETER NAVIGATION FOR PULMONARY VEIN ISOLATION IN PATIENTS WITH PAROXYSMAL ATRIAL FIBRILLATION

Dirk Bastian¹, Johannes Schwab², Andrea Brinker-Paschke¹, Arno Boessenecker¹, Wolfgang Kirste¹, Reinhard Doering¹, Zeynep Karakurt¹, Matthias Pauschinger¹, Konrad Göhl¹

¹ Div. of Cardiology/Electrophysiology, Paracelsus Medical University Nuremberg, Nuremberg, Germany; ² Div. of Cardiology and dpt. for Radiology/Neuroradiology, Paracelsus Medical University Nuremberg, Nuremberg, Germany

Background: Although it is believed that the use of remote magnetic catheter navigation (RMN) will reduce radiation exposure in complex ablation procedures, data proving this hypothesis are still rare. Aim: The study aims to evaluate radiation exposure in patients undergoing RMN-guided primary pulmonary vein (PV) antral isolation (PVAI) for paroxysmal atrial fibrillation (PAF). Methods: Primary RMN-guided PVAI was performed in 233 patients with symptomatic PAF by two operators including the learning curve. The following technologies/techniques were used: Niobe/Epoch®; Siemens AXIOM-Artis zee BP-MN 1–7.5 fps; Carto-RMT non-fluoroscopic mapping (NFM), MR-Image-integration; TEE-guided transseptal puncture, steerable coronary sinus catheter, “single catheter ablation” technique Navistar-RMT Thermocool; and endpoint bidirectional PV-block. The fluoroscopy time (FT) was documented for system calibration (A), transseptal access/catheter positioning (B), and mapping/ablation (C). The procedure duration included a 30-min waiting period after PV-block (skin to skin). Results: Overall, 941 of 945 targeted PVs (99.6 %) were successfully isolated requiring a total FT of 4.7 ± 3.6 min with an effective dose (ED) of only 0.5 ± 0.7 mSv. The major proportion of radiation exposure was attributable to transseptal puncture and catheter positioning (Table 1).

	ARMT/NFM calibration	BTransseptal access, catheter positioning	CMapping, ablation	Total
	(n = 213)	(n = 213)	(n = 213)	(n = 233)
FT [min]	0 ± 0.1	3.7 ± 2.6	0.5 ± 0.8	4.7 ± 3.6
DAP [Gy/cm2]	0 ± 0.1	1.6 ± 2.0	0.3 ± 0.9	2.3 ± 3.4
ED [mSv]	0	0.3 ± 0.4	0.1 ± 0.2	0.5 ± 0.7

Table 1. Radiation exposure of patients undergoing first RMN-guided PVAI for PAF. FT fluoroscopy time, DAP dose area product, ED effective dose. After having finished the learning curve PVAI in the last 150 patients required a total FT of 3.5 ± 2.2 min corresponding to an ED of 0.28 ± 0.3 mSv. Total procedure duration of 300 ± 90 min was reduced to 236 ± 96 min in the last 100 patients. Completely avoiding cardiac tamponade, stroke and atrioesophageal fistula, vascular complications occurred in 7 patients (2.9 %). After a mean follow-up of 11.1 months, 72.5 % of 211 patients were free of atrial arrhythmias. Conclusion: Fluoroscopy durations of 14 to more than 60 min associated with a mean ED of 16.6 mSv (6.6–59.6 mSv) were reported for AF ablation procedures depending on patient’s age, type and duration of AF, underlying cardiac disease, ablation method, technology and operator’s experience. Our single-center evaluation demonstrates that high acute AF ablation success rate can be achieved by means of RMN combined with a low complication rate and reduction of effective radiation dose by more than 90 %. The prolonged overall procedure time could be reduced further on.

13–23 Abstract 15–24

95 ACUTE MANAGEMENT OF ATRIAL FIBRILLATION IN ELDERLY: IS THERE A PLACE FOR IMPROVEMENT?

Antonio Bonora¹, Gianni Turcato², Elena Franchi³, Piero Castiglioni¹, Giulio Trecco², Federico Beltrame³, Oliviero Olivieri⁴, Claudio Pistorelli¹

¹ Department of Emergency and Intensive Therapy - University Hospital of Verona, VERONA, Italy; ² Postgraduate School of Emergency Medicine - University of Verona, VERONA, Italy; ³ Department of Cardiology - Hospital University of Verona, VERONA, Italy; ⁴ Department of Internal Medicine and Postgraduate School of Medicine - University of Verona, VERONA, Italy

Acute management of atrial fibrillation (AF) in elderly is still a matter of debate. Although underlying structural heart disease often forces to rate control strategy, aging itself appears in many cases to lead to a non-aggressive approach. Therefore, we considered our experience to evaluate if management of AF in elderly could be improved. From January 2008 to December 2012 in the Emergency Department of University Hospital of Verona, 1437 patients (676 males, 761 females, mean age 70 years) were observed for recent-onset AF. Out of these, 601 patients (41.8 %) were over 75 years, with an expected prevalence of females and cardiovascular disease. Attempt at cardioversion rate was significantly less in over 75 groups compared to younger ones (43.9 % vs 69.4 %, p < 0.05). Surprisingly, even in the former group, timing >48 h was the main contraindication (57.3 %). In 264 patients over 75 (96 males, 168 females, mean age 81 years), we attempted at pharmacological cardioversion. As well as in younger group, onset <24 h was the predominant timing (89 %) and palpitations the main symptom (76 %). Being considered most manageable and safer, amiodarone was the treatment of choice (69 % of patients). We reached a restoration of sinus rhythm within 12 h in 61.3 % of the cases, ranging from 54.4 % of amiodarone to 85 % of flecainide. In 8 patients, we performed an electrical cardioversion after pharmacological approach failed. Overall successful rate was thus 64.4 %. We reported a very low complications rate (3 %), with any regard to treatment strategy. A larger number of patients were hospitalized after ED stay (55.3 %). Hospitalization rate was significantly higher in older group (55.3 vs 34 %, p < 0.05), but persistence of high-rate AF remained the main reason to (35.6 %), in like manner with younger group. Although elderly people are considered to be a fragile group, the pattern of presentation of recent-onset AF similar to overall population seems to discredit aging itself could be a contraindication to “rhythm control” strategy. Therefore, an improvement in the acute management of AF and a reduction of hospitalization rate could be expected even in elderly, by means either a larger use of class 1c antiarrhythmic drugs, when allowed by clinical conditions, or a most accurate indication to “rate control” therapy, when restoration or maintenance of sinus rhythm is not likely. A 2-year follow-up is carried out to compare “rhythm control” with “rate control” strategy regarding to wellness and disease-free period.

13–24 Abstract 15–54

96 QUANTIFICATION OF THE RELATIONSHIP BETWEEN LATE-GADOLINIUM INTENSITY AND CONDUCTION VELOCITY IN THE LEFT ATRIUM

Rheeda L Ali¹, Norman A Qureshi¹, Chris D Cantwell¹, Caroline H Roney¹, Phang Boon Lim¹, Jennifer H Siggers¹, Spencer J Sherwin¹, Nicholas S Peter¹

¹ Imperial College London, London, UK

Introduction: Late-gadolinium enhanced (LGE) cardiac MRI (CMRI) is thought to be an indicator of regions of disease and abnormal conduction. We developed a technique to quantify the relationship between LGE-CMRI intensity and localised conduction velocity (CV). Method: Six electrical datasets were collected from five patients. The epicardial surface was manually segmented from the LGE-CMRI. The maximum voxel intensity (normalised as SDs above blood pool mean) along a 3-mm inward-facing normal was assigned to each vertex of a triangulation of the surface (Fig. A). Unipolar electrogram data were collected from the atrial wall paced (cycle length 600 ms) either from the coronary sinus (CS) or left atrial appendage (LAA). The electro-anatomic surface and electrogram data were exported from the mapping system (EnSite Velocity). The electro-anatomic surface was the registered with the CMRI surface using an automated landmark selection algorithm and the registration error was estimated. Poor-quality electrograms were rejected. A novel quantitative approach was used to select triplets of electrodes and relate average CV with average normalised voxel intensity. Results: Surface registration error was 3.32 ± 0.60 mm. When the minimum electrode distance was chosen as twice the registration error, a statistically significant (p < 0.05) negative correlation coefficient was observed for four datasets (CS −0.55, −0.75; LAA −0.18, −0.27). Example correlation is shown in Fig. B. Non-planar and non-circular complex activation sequences were found to produce a broad spread of conduction velocities. Conclusion: Our method suggests a reduction in CV in regions on the posterior wall with greater enhancement on LGE-CMRI. This can be used to interrogate both the underlying structural and functional substrates in patients with AF.

13–25 Abstract 15–52

97 THE RISK OF CARDIOVASCULAR EVENTS IN PATIENTS WITH ATRIAL FIBRILLATION AFTER ELECTRICAL CARDIOVERSION

Olga Litunenko¹, Oskars Kalejs², Aldis Strelnieks¹, Marina Kovalova³, Iveta Sime⁴, Milana Zabunova², Biruta Tilgale⁵, Ilze Konrade⁵, Evija Miglane², Kaspars Kupics², Irina Pupkevica¹, Aivars Lejnieks⁵

¹ Riga Stradins University, Riga, Latvia; ² P. Stradins Clinical University Hospital, Riga, Latvia; ³ Jelgava Regional Hospital, Jelgava, Latvia; ⁴ Liepaja Regional Hospital, Liepaja, Latvia; ⁵ Riga East University Hospital, Riga, Latvia

Atrial fibrillation (AF) is the most common type of sustained arrhythmia which may be associated with serious complications: cerebrovascular accidents, systemic embolism, heart failure and an increased risk of bleeding in patients who take anticoagulants. Aim: The study aims to evaluate clinical events in patients following electrical cardioversion (ECV) according to cardiovascular risk factors, CHA2DS2-VASc scale and pharmaco-therapeutical methods used, with the use of anticoagulants included. Material and methods: Two hundred and sixty prospective and 225 retrospective patients with atrial fibrillation, who had an ECV in 2013 in Latvian Centre of Cardiology. The data acquired in medical data bases and control questionnaire were used. Results: The most common cardiovascular risk factor was found to be arterial hypertension (AH) (83.1 %), chronic heart failure (CHF) (66.6 %) and metabolic syndrome (16.1 %). Diabetes was less common (12.6 %), patients after myocardial infarction, cerebrovascular accidents (5.6 %) and TIA (3.9 %). Thromboembolism risk evaluated with CHA2DS2-VASc score in 38 (7.8 %) patients was 1 and in 447 (92.2 %) ≥2 points. The mean score was 3.8. A month after ECV the following cardiovascular episodes were observed: acute coronary syndrome (ACS) (0.9 %), CHF decompensated (0.4 %), PE/DVT (0.4 %), AF recurrence (20.5 %). Over 3 months the events were ACS (0.5 %) CHF decompensation (0.5 %), PE/DVT (0.5 %) and AF recurrence (26.3 %). Six months after ECV, 0.7 % of patients had ACS, 2 % had CHF decompensation, 0.7 % had PE/DVT, 1.4 % had cerebral stroke and 36.4 % had AF recurrence. The occurrence of bleeding on warfarin ranged from 4.62 % (p = 0.013) to 6.62 % (p = 0,067), for aspirin from 3.13 % (p = 0.119) to 3.31 (p = 0.067). The occurrence of bleeding during 1 and 3 month on dabigatran was 1.2 % and for rivaroxaban 1.5 %. Conclusion: The occurrence of cardiovascular events following cardioversion is similar to that reported in the literature except for AH and CHF, which were higher in this study. The risk of clinical episodes using CHA2DS2-VASc score was higher than in other studies. Most often bleeding occurred while using warfarin during the first month after ECV. Using novel oral anticoagulants according to the guidelines before and after ECV is safer than with warfarin

13–26 Abstract 15–53

98 A NOVEL METHOD FOR ROTOR TRACKING USING BIPOLAR ELECTROGRAM PHASE TESTED ON SIMULATED, CELL CULTURE AND CLINICALLY ACQUIRED ELECTROGRAMS

Caroline H Roney¹, Rasheda A Chowdhury¹, Chris D Cantwell¹, Norman A Qureshi¹, Emmanuel Dupont¹, Phang Boon Lim¹, Jennifer H Siggers¹, Fu Siong Ng¹, Nicholas S Peters¹

¹ Imperial College London, London, UK

Introduction: Assessing the location and stability of rotors can help target ablation therapy for atrial fibrillation (AF). Phase singularity (PS) tracking techniques are applied to unipolar electrogram (UE) and action potential (AP) data, but not commonly to bipolar electrogram (BE) data, which contains local activation only. We developed and tested a technique to track PSs from simulated, cell culture and clinically acquired BE data. Methods: UEs were computed (at 2–10-mm spacing) from simulated rotor AP data. UEs were also recorded from a cell culture monolayer of HL-1 atrial myocytes using a multi-electrode array (MEA, 8 × 8, 700 mm spacing). BEs were computed from pairs of UE. UE and BE were also recorded from an a-focus catheter (4-mm spacing) during human AF. BEs were filtered and the moving-mean removed from the signal so as to conserve small-amplitude deflections due to wavefront direction. The phase angle was calculated, and PS trajectories and lifetimes were determined using automated algorithms. Wavefront dynamics and singularity positions computed using UE, BE and AP data were compared. Results: Interpolated wavefront patterns were qualitatively similar between AP, UE and BE for simulated data and between UE and BE for cell culture and clinical data, where differences were largest for clinical data (Fig). For cell culture MEA data, the average framewise core location difference was 570 ± 263 mm and the average number of PS per frame was 0.75 ± 0.63. The mean number of PS per frame for clinical a-focus data was slightly larger for BE than UE (0.49 ± 0.73 vs 0.31 ± 0.55). Conclusion: BE phase is as effective as AP phase for rotor tip detection when using simulated data and performed similarly to UE for cell culture and clinical data. This suggests it may be used clinically as an alternative method to UE phase.

13–27 Abstract 15–48

99 RISK FACTORS OF RECURRENCE ATRIAL FIBRILLATION AFTER ELECTRICAL CARDIOVERSION

Olga Litunenko¹, Aldis Strelnieks², Milana Zabunova³, Kaspars Kupics³, Kristine Jubele³, Janis Pudulis², Sandis Sakne³, Maija Vikmane³, Marina Kovalova⁴, Ilze Vinkalna¹, Aivars Lejnieks², Oskars Kalejs³

¹ Riga Stradins University, Riga, Latvia; ² Riga East University Hospital, Riga, Latvia; ³ P. Stradins Clinical University Hospital, Riga, Latvia; ⁴ Jelgava Regional Hospital, Riga, Latvia

Atrial fibrillation is associated with increased risk of embolic events and development of heart failure. Electrical cardioversion is a safe, fast and effective way to restore sinus rhythm, but does not prevent the high possibility of recurrent atrial fibrillation. Therefore, antiarrhythmic therapy to prevent recurrences is needed. Aim of study: The study aims to evaluate the effectiveness of antiarrhythmic drug therapy and risk factors of recurrences after electrical cardioversion. Methods: Review the medical data records and information from control phone calls 1, 3 and 6 months after electrical cardioversion of 256 prospective and medical records of 229 retrospective patients undergoing electrical cardioversion of atrial fibrillation during year 2013 at Latvian Centre of Cardiology. For statistical analysis, program SPSS 17.0 was used. Results: Atrial fibrillation recurred in 32.6 % of patients. There was statistically significant higher rate of recurrences (OR 0.324; p = 0.020) and hospitalizations (p = 0.010) in case of chronic kidney disease over 1, 3 and 6 months after electrical cardioversion. Patients in age group from 45 to 55 (40.5 %) had atrial fibrillation recurrences more frequently during 3 months (OR 0.648; p = 0.011). IC and III class antiarrhythmic drugs were prescribed in 83.1 % of cases with amiodarone in 62.1 %. There were fewer recurrences with amiodarone (33.3 %) and sotalol (33.3 %, than with propafenone (63.6 %) and aethacizine (83.3 %)) (p = 0.002). Beta-blockers were prescribed in 81.9–86.8 % of patients, and angiotensin-converting enzyme inhibitors—55.5–58.1 % of patients. There was fewer episodes of recurrent atrial fibrillation in patient groups, where statins (26.9 % (n = 32) vs. 38.6 % (n = 39); p = 0.044), aldosterone antagonists (12.5 % (n = 3) vs. 34.7 % (n = 68); p = 0,036) and diuretics (15.4 % (n = 4) vs. 41.5 % (n = 51); p = 0.014) were used. Conclusion: Recurrent atrial fibrillation occurs in one third of patients after electrical cardioversion of atrial fibrillation. The use of beta-blockers and ACEI after electrical cardioversion is frequent. The use of statins, diuretics and aldosterone antagonists decreases the number of atrial fibrillation recurrences. Amiodarone is more effective and decreases significantly the risk of recurrence of atrial fibrillation as compared with propafenone, ethacizine and sotalol. A significant higher risk of atrial fibrillation recurrences and hospitalization was noted during the 6 months after electrical cardioversion in patients with chronic kidney disease and in the 3-month follow-up in patients aged 45–55 years.

13–28 Abstract 15–47

100 ADDITION OF ATRIAL ECTOPY AND NT-PROBNP TO FRAMINGHAM ATRIAL FIBRILLATION RISK ALGORITHM IMPROVES RISK PREDICTION

Preman Kumarathurai¹, Mette Mouridsen¹, Nick Mattsson¹, Bjørn Larsen¹, Olav Nielsen¹, Thomas Gerds², Ahmad Sajadieh¹

¹ University Hosptial of Bispebjerg, Copenhagen, Denmark; Department of Biostatistics, Copenhagen University, Copenhagen, Denmark

Background: Atrial fibrillation (AF) is a common arrhythmia associated with increased morbidity. Models for prediction of AF can be relevant in examining the AF pathogenesis and AF prevention therapies. We aimed to investigate whether elevated NT-proBNP or increased rate of premature atrial contractions (PACs) improved risk prediction for AF compared to Framingham AF risk score. Methods: Subjects from the population-based cohort in the Copenhagen Holter Study, consisting of 678 men and women between 55 and 75 years of age and with no history of prior atrial fibrillation, stroke or cardiovascular disease, were followed for the diagnosis of incident AF or death (median follow-up time14.4 years). Baseline examination included physical examination, laboratory testing and 48-h ambulatory ECG monitoring. Subjects with missing values were excluded, and Framingham risk score for AF was calculated for the remaining 646 subjects. In order to investigate the predictive ability ofPAC (log-scale) and NT-proBNP (log-scale), we computed the time-dependent area under the ROC curve (AUC) for the AF status 10 years after the baseline examination. Results: Two hundred and sixty-nine subjects (41.6 %) were women, mean systolic blood pressure was 156.2 mmHg and 72 subjects (11.1 %) had diabetes. Median NT-proBNP was 6.7 mmol/L (IQR: 3.6–13.5) and median PAC count was 1.4 beats/h (IQR 0.6–4.5). During the 14.4 years of observation, 77 (11.4 %) subjects developed AF and 224 (33.0 %) died. In multiple Cox model adjusted for Framingham AF risk score, log-transformed NT-proBNP and log-transformed PAC was associated with a significant increase in AF risk (HR 1.44 [95 %CI 1.13–1.82], p = 0.001; HR 1.22 [95 % CI 1.09–1.39] p = 0.002). The addition of PAC to the Framingham AF risk model significantly improved AF risk discrimination (AUC 65.7 vs. 72.2; p = 0.0072), while the addition of NT-proBNP did not (AUC 68.4; p = 0.23). The addition of both PAC and NT-proBNP to the Framingham risk score also improved the AF discrimination capability (AUC 72.3; p = 0.013).

Marker	AUC	p value
Framingham score	65.7 [60.85;78.77]	–
Framingham score + PAC	72.2 [66.35;84.29]	0.0072
Framingham score + NT-proBNP	68.4 [61.98;81.43]	0.23
Framingham score + PAC + NT-proBNP	72.3 [66.43;84.22]	0.013

Table 1. Conclusions: AF risk discrimination was significantly improved by addition of PAC to the existing Framingham AF risk prediction model but not by addition of NTproBNP.

13–29 Abstract 15–43

101 BALLON MITRAL VALVULOTOMY FOR PATIENTS WITH MITRAL STENOSIS IN ATRIAL FIBRILATION: IMMEDIATE AND LONG TERM PROGNOSIS

Marouane Mahjoub¹, Majed Hassine¹, Ghassan Cheniti¹, Ibtihel Mechri¹, Majdi Ben Massaoud¹, Zohra Dridi¹, Fethi Betbout¹, Habib Gamra¹

¹ Cardiology department A: Fattouma Bourguiba University Hospital, Monastir, Tunisie

Background: Atrial fibrillation (AF) is a common finding in patients with severe mitral stenosis requiring balloon mitral valvulotomy (BMV). Its immediate and long-term prognosis remains controversial. We sought to evaluate the effect of AF on the immediate and long-term (23 years) outcome of patients undergoing BMV. Methods: The immediate procedural and the long-term clinical outcome after BMV of 139 patients with AF were collected and compared with those of 381 patients in normal sinus rhythm (NSR). Results: Patients with AF were older (43.3 vs. 29.7 years; p < 0.001) and had frequently a history of systemic embolism (9.4 vs. 1.6 %, p < 0.001) and of mitral commissurotomy (28.1 vs. 19.4 %, p = 0.035). Symptoms were similar between the two groups (NYHA > II 48.9 vs. 49.9 %, p = 0.648). Patients with AF had more, frequently, a Wilkins score >8 (51.4 vs. 30.9 %, p < 0.001), a larger left atrium (41 vs. 32 cm², p = 0.001) and a lower transmitral gradient (11.1 vs. 16.6 mmHg, p < 0.001). BMV was equally successful in the two groups (90.6 vs. 94 %, p = 0.187) but resulted in a smaller post BMV area (2 vs. 2.15 cm², p = 0.012) with a lower mitral valve area gain (0.9 cm² vs. 1 C, p = 0.015). BMV was not associated with a higher risk of complications (4.3 vs. 4.7 %, p = 0.844). After a mean follow-up of 74 months, patients with AF had the same rate of restenosis (28.3 vs. 25.6 %, p = 0.96) but required more frequently a mitral valve replacement (16.3 vs. 7.7 %, p = 0.012). They also experienced higher rates of systemic embolism (3.8 vs. 0.6 %, p = 0.018) and had a lower rate of event free survival (freedom from death, restenosis and systemic embolism) (52.2 vs 68.8 %, p = 0.047).In the group of patients in AF, predictive factors for combined adverse events including death, restenosis, and systemic embolism and mitral valve replacement are as follows: post BMV area <2 cm² (OR 2.5, 95 % CI [1.2; 5.18], p = 0.014), procedural complications including severe mitral regurgitation and tamponade (OR 3.95, 95 % CI [1.4; 11.13], p = 0.009) and NYHA class II during follow up (OR 3.46,, 95 % CI [2.09; 5.73], p < 0.001). Conclusion: Our data support the fact that patients with AF have worse immediate and long term outcomes after BMV. Post BMV area <2 cm², procedural complications and dyspnea predict adverse events during follow-up.

13–30 Abstract 15–42

102 SURFACE ECG IDENTIFICATION OF PERSISTENT AF DRIVER ACTIVITY DETECTED BY NONINVASIVE ELECTROCARDIOGRAPHIC IMAGING

Torsten Konrad¹, Sebastien Knecht², Isabel Deisenhofer³, Thomas Arentz⁴, Mattias Duytschaever⁵, Thomas Neumann⁶, Bruno Cauchemez⁷, Jean-Paul Albenque⁸, Thomas Münzel⁹, Cathrin Theis¹, Thomas Rostock¹

¹ II. Med. Clinic, Department for Electrophysiology, Johannes Gutenberg-University, Mainz, Germany; ² CHU Brugmann, Brussels, Belgium; ³ Dept. of Electrophysiology, Deutsches Herzzentrum München, Technische Universität, Munich, Germany; ⁴ Universitäts-Herzzentrum Freiburg-Bad Krozingen, Bad Kronzingen, Germany; ⁵ Univ Hospital Ghent, Ghent, Belgium; ⁶ Kerckhoff Heart Center, Bad Nauheim, Germany; ⁷ Clinique Ambroise Paré, Neuilly-sur-Seine, France; ⁸ Clinique Pasteur, Toulouse, France; ⁹ II. Med. Clinic, Johannes Gutenberg-University, Mainz, Germany

Introduction: Body potential mapping and phase analysis of unipolar signals has been implemented to identify rotor or focal driver activity in patients with persistent AF. This study aimed to identify specific surface ECG activation patterns at the time of stable driver activity (SDA) identified by noninvasive electrocardiographic imaging (ECGI). Methods: Surface ECG (lead V1) and phase maps from 17 patients (male = 76 %, age 64.2 ± 4.5 years, BMI 30 ± 5.8, uninterrupted AF duration 5.7 ± 3.3 months) undergoing persistent AF ablation during the AFACART study were analyzed. From each patient, three pauses (defined as ≥ 1 s between the QRS-complexes) with SDA (SDA pauses) and three pauses without SDA (non-SDA pauses) were analyzed (total 102 pauses). For the purpose of this study, SDA was defined as reentrant activity with ≥ 2 completed 360° rotations or ≥ 3 repetitive focal discharges. ECGI was performed with the ECVUETM system (CardioInsight, USA). The following ECG score for SDA identification was developed: 1. changes in single beat AFCL ≥ 10 ms, 2. changes in F-wave amplitudes ≥ 0.05 mV, and 3. changes of F-wave polarity (positive/biphasic/negative). The observation of each of the above parameters was counted with 1 point. Results: The developed score was significantly higher during pauses with stable driver activity as compared to those without (2.11 ± 0.87 vs. 0.31 ± 0.52, p = 0.01). The positive predictive value (PPV) for a score ≥ 2 was 0.97, the negative predictive value (NPV) 0.76. The best predictive value of the score parameters was identified for the change of AFCL ≥ 10 ms during pauses (PPV 0.95, NPV 0.87). The occurrence of SDA was associated with organization of the global activation pattern in approximately half of the patients. Conclusion: 1. We developed a new scoring system for the identification of SDA in the conventional surface ECG.2. The most important predictor for the presence of a SDA is a significant change in AFCL during pause. 3. Stable driver activity appears to “coordinate” the atrial activation wave-fronts resulting in changes of F-wave characteristics in the surface ECG. 4. Typically, the occurrence of SDA leads to deceleration of AFCL, increase of F-wave amplitude and F-wave polarity shift.

Poster session B part 1

Sunday, April 19, 2015

Posters exposed from 02:00 PM to 05:00 PM

Presenters and chairpersons present from 02:00 PM to 03:30 PM

Arrhythmias and heart disease

14–1 Abstract 17–15

103 VENTRICULAR TACHYARRHYTHMIA IN PATIENTS WITH CONGENITAL HEART DISEASE: WAIT-AND-SEE OR PREDICTABLE?

Christophe Teuwen¹, Tanwier Ramdjan¹, Joris Vriend², Marco Gotte², Sander Molhoek³, Reinhart Dorman⁴, Jurren van Opstal⁴, Thelma Konings⁵, Pepijn van der Voort⁶, Etienne Delacretaz⁷, Ameeta Yaksh¹, Nienke Wolfhagen¹, Peter de Klerk¹, Dominic Theuns¹, Maarten Witsenburg¹, Jolien Roos-Hesselink¹, Paul Knops¹, Eva Lanters¹, John Triedman⁸, Ad Bogers¹, Natasja de Groot¹

¹ Erasmus Medical Centre, Rotterdam, Netherlands; ² Haga Hospital, The Hague, Netherlands; ³ Amphia Hospital, Breda, Netherlands; ⁴ Medisch Spectrum Twente, Enschede, Netherlands; ⁵ VU University Medical Centre, Amsterdam, Netherlands; ⁶ Catharina Hospital, Eindhoven, Netherlands; ⁷ Inselspital, University of Bern, Bern, Switzerland; ⁸ Boston Children’s Hospital, Harvard Medical School, Boston, MA, USA

Background: Ventricular tachycardia (VT) and ventricular fibrillation (VF) have been reported as common late post-operative complications in patients with congenital heart defects (CHD). These ventricular tachyarrhythmia (VTA) can lead to increased morbidity and are associated with sudden cardiac death. We aimed to investigate the occurrence of VTA in CHD patients over time. In addition, we looked for new clinical and electrophysiological predictors of VTA. Methods: CHD patients with a documented episode of VTA on an electrocardiogram (ECG) or 24-h Holter registration were analyzed. Patients were divided into groups according to their severity of CHD. Furthermore, VTA were classified as non-sustained VT (nsVT), sustained VT (sVT) or VF. On ECGs, the QRS duration (QRS) and QTc interval (QTc) were reviewed <1 year prior to VTA and 5 years earlier. Finally, echocardiograms were assessed <1 year before VTA. Results: VTA episodes were documented in 149 patients (60 % male) at a mean age of 40 ± 14 years (range 15–70 years); VTA consisted of nsVT (N = 110), sVT (N = 23) and VF (N = 16). QRS and QTc did not change (QRS 132 ± 31 versus 129 ± 28 ms, p = 0.56; QTc 395 ± 40 versus 403 ± 36 ms, p = 0.11). Echocardiograms were available in 125 patients, of whom 23 had a depressed right and/or left ventricular function. Fifty-one (34 %) patients received an ICD; VTA recurred in 15 (29 %) patients of them during a follow-up period of 7 ± 4 years; inappropriate shocks caused by supraventricular tachycardia (SVT) occurred in 13 patients (25 %). Conclusion: VTA initially developed at a mean age of 40 years, which was approximately 30 years after the first cardiac surgery. Intra-ventricular conduction delay, dispersion in ventricular refractoriness and cardiac function were of limited value in order to predict development of VTA. In patients with an ICD, VTA recurred frequently during long-term follow-up. Moreover, SVT developed often as well, causing inappropriate shocks.

14–2 Abstract 15–49

104 SIGNIFICANT DIFFERENCES IN PRESENTATION OF ATRIAL FIBRILLATION IN PATIENTS WITH STEMI AND NON-STEMI BUT SIMILAR ALL-CAUSE MORTALITY RISK AT 30 DAYS

Dritan Poci¹, Marianne Hartford², Thomas Karlsson², Kenneth Caidahl³, Nils Edvardsson²

¹ Department of Cardiology, Univ. Hospital Örebro, Örebro, Sweden; ² Institute of Medicine, Department of Molecular and Clinical Medicine/Cardiology, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden; ³ Department of Molecular Medicine and Surgery, Karolinska Institutet, Stockholm, Sweden

Background: The aim of this study was to determine the prognostic implications of pre-existent and new-onset atrial fibrillation AF in patients (pts) with ST-segment elevation myocardial infarction (STEMI) and non-STEMI. Methods and results: Among 2335 consecutive patients with ACS, 54 pts had known permanent, 37 known paroxysmal AF and 54 their first ever AF on admission, while 184 pts developed their first ever AF during hospitalization. There were 859 pts with STEMI and 792 with non-STEMI. Any AF occurred in similar proportions of STEMI and non-STEMI pts, 19 vs 23 % (p = 0.06). There were statistically a significant difference in the distribution of AF subgroups between AF patients with STEMI and AF patients with non-STEMI (p < 0.0001). In STEMI patients, new AF during hospitalization was found in 60 % of the AF patients versus 33 % in non-STEMI patients. Corresponding proportions for known paroxysmal AF were 21 and 38 % in the STEMI and non-STEMI group, respectively. The 30-day mortality was significantly higher in patients with any AF as compared to no AF, both in STEMI patients, 21 vs. 9 % (p < 0.0001), and in non-STEMI patients, 12 vs. 5 % (p = 0.002). In STEMI patients, but not in non-STEMI patients, there was a statistically significant difference in mortality among the AF subgroups (p = 0.03 and p = 0.56, respectively). Conclusion: The presentation of AF differed between patients with STEMI and patients with non-STEMI. Thirty-day mortality was more than doubled in patients with any AF as compared to patients without AF, both among those with STEMI and those with non-STEMI. In STEMI patients, the 30-day mortality was highest in the subgroup with known permanent AF, while there was no significant difference among AF subgroups in non-STEMI patients.

14–3 Abstract 07–17

105 INCIDENCES OF DYSRHYTHMIA IN THE OPERATING ROOM IN CHILDREN AFTER SURGERY FOR CONGENITAL HEART DISEASE

Charlotte Houck¹, Ameeta Yaksh¹, Eva Lanters¹, Lisette van der Does¹, Christophe Teuwen¹, Maarten Witsenburg¹, Jolien Roos-Hesselink¹, Ad Bogers¹, Natasja de Groot¹

¹ Erasmus Medical Center, Rotterdam, Netherlands

Background: Several studies have reported incidences of dysrhythmia in the intensive care unit in children after surgery for congenital heart disease (CHD) varying from 15 to 48 %. However, the incidence of dysrhythmia in the operating room (OR) in this population has never been reported. The aims of this study are to determine the incidence of dysrhythmias in the intra and immediate postoperative period in children after surgery for CHD and to identify pre and intraoperative risk factors for the development of these dysrhythmias. Methods: We included 84 patients younger than 18 years who underwent cardiac surgery for various CHD. Continuous rhythm registrations were analyzed from the moment the aortic clamps were taken off or, when aortic clamps were not used, the sternum was closed until the moment the child left the OR. Rhythm registrations were analyzed for the occurrence of atrial and ventricular tachyarrhythmia, atrioventricular conduction blocks (AVB), junctional rhythm and ectopic atrial rhythm. Results: Second-degree AVB was observed in 42 % of patients and third-degree AVB in 25 %. Longer duration of aortic cross clamp time or bypass time was associated with a higher incidence of AVBs. However, these factors appeared not to influence the incidence of junctional or ectopic atrial rhythm, which were both observed in 23 % of all patients. Four patients, all with a VSD, had more than 30 ventricular premature beats (VPBs) per hour and 14 patients, of which 9 had a VSD, had 10 to 30 VPBs per hour. Ventricular runs were also more often observed in patients with a VSD or univentricular heart. Atrial fibrillation (N = 1), non-sustained ventricular tachycardia (N = 1) and ventricular fibrillation (N = 1) were infrequently observed. When leaving the OR, 93 % of all patients had sinus rhythm and 6 % had junctional or ectopic atrial rhythm. One patient (1 %) had received a temporary atrial pacemaker lead for sinus node dysfunction, which recovered a few days postoperatively. Conclusion: Dysrhythmia and AVB were frequently observed in the OR in children after surgery for CHD. However, most children (93 %) left the OR in sinus rhythm. Longer duration of aortic cross clamp time and bypass time were risk factors for development of AVB. The presence of a VSD was associated with a higher incidence of ventricular tachyarrhythmia.

14–4 Abstract 14–12

106 DO ECTOPIC SUPRAVENTRICULAR PREMATURE BEATS PREDICT EARLY NEW-ONSET ATRIAL FIBRILLATION AFTER CORONARY ARTERY BYPASS SURGERY?

Ameeta Yaksh¹, Charles Kik¹, Eva A.H. Lanters¹, Upaashna Chigharoe¹, Paul Knops¹, Maarten J.B. Van Ettinger¹, Marcel C.J. De Wijs¹, Peter Van de Kemp², Jan Hofland¹, Ad J.J.C. Bogers¹, Natasja N.M. De Groot¹

¹ Erasmus MC, Rotterdam, Netherlands; ² Sorin, Rotterdam, Netherlands

Background: Early new-onset postoperative atrial fibrillation (PoAF) occurs frequently after CABG, but the exact mechanism is unknown. In the general population, frequent supraventricular premature beats (SVPBs) are associated with AF. Whether SVPBs also play a role in development of PoAF is unknown. This study examines the frequency and burden of postoperative supraventricular dysrhythmia SVPBs, SV-couplets/runs in patients with coronary artery disease in relation to PoAF. Methods: Patients (N = 105, 83 male, 66 ± 9 years) undergoing CABG were included. Postoperative continuous rhythms were recorded and semi-automatically analysed in multichannel Holter scanning software SynescopeTM (Sorin Group). SVPBs were defined as singles ≥25 % shorting of SVPB’s cycle length (CL) compared to the average CL of the two preceding beats, couplets or runs (containing ≥3 beats and during < 30 s). PoAF was defined as episodes lasting ≥30 s. Single SVPBs prematurity index (PI%) was assessed by dividing its CL to the averaged CL of the two preceding beats. Single SVPBs burden per patient was obtained by dividing the sum of all SVPB by the total number of beats. The burden of couplets and runs was defined as the total duration of all couplets/runs divided by the recording time. The top 10th and 25th percentile of atrial characteristics were used to predict PoAF. Results: Recorded in 8231 h, 42,583,846 beats were analysed. SVPBs, SV-couplets, SV-runs and PoAF occurred in, respectively, 100, 90, 81 and 28 % of the patients. PoAF developed in 29 (28 %) patients. Patients with PoAF had a significantly higher frequency and burden of single SVPBs/couplets/runs compared to patients without PoAF (Table 1). Similar results were demonstrated for single SVPBs PI. Using the atrial dysrhythmia’s cutoff values, PoAF could be predicted by SVPBs≥57/h (OR 6.4), ≥1196/day (OR 8.4), SVPB burden≥1.2 % (OR 6.1), SV-run≥0.2/h (OR 5.1), ≥5/day (OR 4.7) and SV-run burden≥0.2 % (OR 9.7). Conclusion: Supraventricular dysrhythmia occurs in the majority of patients after CABG, whereas PoAF develops in 28 % of the patients. Independent risk factors for development of AF after CABG were the frequency and burden of SVPBs and SV-runs. Hence, these parameters could be used to identify patients at risk for developing PoAF and allows preventive measures to be taken.

	No PoAF	PoAF	P value
SVPB per day/burden (‰)	178/0.02	540/0.09	0.01/0.00
Prematurity index (%)	65	63	0.02
SV-couplet per day/burden (‰)	22/0.02	45/0.05	0.09/0.05
SV-run per day/burden (‰)	6/0.2	34/0.9	0.02

14-5 Abstract 15–55

107 PERIOPERATIVE INDUCIBILITY OF AF: PREDICTOR FOR DEVELOPMENT OF EARLY POSTOPERATIVE AF?

Eva Lanters¹, Ameeta Yaksh¹, Lisette van der Does¹, Christophe Teuwen¹, Paul Knops¹, Charles Kik¹, Ad Bogers¹, Natasja de Groot¹

¹ Erasmus MC, Rotterdam, Netherlands

Introduction: Development of Atrial Fibrillation (AF) requires a trigger, initiator and a substrate. Human epicardial mapping studies are currently being performed to acquire insight into the substrate underlying AF. For these studies, electrical induction of AF is essential. The aim of the present study is to assess whether perioperative inducibility of AF predicts development of early postoperative AF (PoAF). Methods: Patients (n = 181) undergoing coronary artery bypass grafting without a history of AF were included for an epicardial mapping study of the entire atria (mapping array 192 electrodes) during sinus rhythm and AF. In all patients, fixed rate atrial pacing (250–300–350 bpm) was used for induction of AF. Fibrillation maps at ten different atrial sites during 10 s of AF were analyzed using custom made software. AF was defined as a beat-to-beat change in (1) activation pattern, (2) cycle length and (3) electrogram morphology. Early PoAF was detected by continuous rhythm registration/ECGs during the first five post-operative days. Results: In 150 (82.3 %) patients, either AF (n = 128, 82.1 %) or atrial flutter (AFL, n = 22, 14.7 %) was successfully induced. AF sustained throughout the entire mapping procedure in 74 patients (57.8 %), whereas 54 (42.2 %) patients required re-induction. In 31 (17.1 %) patients, atrial tachyarrhythmia could not be induced. Early PoAF developed in only 3 (9.1 %) of patients without inducible arrhythmia versus 32 (21.3 %) patients with inducible arrhythmia, including 15 (20.3 %) patients with sustained and 13 (24.1 %) patients with non-sustained induced AF and 4 (18.2 %) patients with induced AFL. Conclusion: Perioperative inducibility of AF or AFL is a predictive parameter for development of early PoAF. There is no difference between induction of sustained or non-sustained AF and development of early PoAF.

14–6 Abstract 17–12

108 EARLY VENTRICULAR TACHYARRHYTHMIAS AFTER CORONARY ARTERY BYPASS GRAFTING SURGERY: IS IT A REAL BURDEN?

Elisabeth Mouws¹, Ameeta Yaksh¹, Paul Knops¹, Charles Kik¹, M.J.B. van Ettinger¹, M. de Wijs¹, P. van de Kemp², Eric Boersma¹, Ad Bogers¹, Natasja de Groot¹

¹ Erasmus Medical Center, Rotterdam, Netherlands, ² Sorin Group, Amsterdam, Netherlands

Background: Ventricular tachyarrhythmias (VTA) have been reported with incidences varying from 0.95 to 5 % after coronary artery bypass grafting (CABG). Ventricular dysrhythmias (VD) (ventricular premature beats (VPBs), ventricular couplets (Vcouplets) and ventricular runs (Vruns)) on the other hand have so far not been examined. The goal of this study is to examine characteristics of VD and VTA during a postoperative follow-up period of 5 days using continuous rhythm registrations. In addition, we determined predictive factors of VD/VTA. Methods: The study population consisted of 105 successive patients undergoing elective CABG in the Erasmus MC Rotterdam. Postoperative continuous rhythm registrations were obtained and analyzed. Independent predictors of ventricular arrhythmia were identified by multivariate binary logistic regression analysis in a stepwise fashion. Incidences and burdens of VD/VTA were calculated. Results: One hundred five patients (83 male (79 %), age 65 ± 9 (42–83) years) were included. A total of 430,006 VPBs, 8032 Vcouplets and 2153Vruns were found in these patients. VPBs, Vcouplets and Vruns occurred in, respectively, 100, 82.9 and 48.6 % of patients, with corresponding burdens of 0.05, 0 and 0 %. Incidences were highest on the first postoperative day. Sustained VT and VF did not occur in our cohort. Independent risk factors for VD included male gender, mitral valve insufficiency, hyperlipidemia and age≥60 years. Conclusion: VDs are common in patients with coronary artery disease after CABG. Despite high incidences of these dysrhythmias, corresponding burdens are low and VTA did not occur. Future studies including patients with VTA are necessary to analyze the prognostic value of characteristics of VD for VTA in the early postoperative phase and long-term survival.

14–7 Abstract 08–14

109 SYMPTOMATIC HIGH DEGREE HEART BLOCK COMPLICATING SYSTEMIC SARCOIDOSIS

Malka Yahalom¹, Ofir Koren², Yoav Turgeman¹

¹ Cardiolog Department, Ha’Emek Medical Center, Afula, Israel; ² Internal Medicine C, Ha’Emek Medical Center, Afula, Israel

Background. Myocardial involvement in sarcoidosis may be a benign disease or in some instances may be a life-threatening condition. We report two cases of high-degree AV block associated with systemic sarcoidosis. Purpose. The purpose is to raise awareness of cardiac involvement in sarcoidosis and its clinical implications. Patients and methods. Patient 1. This 43-year-old male, presented Stokes-Adams syndrome, related to paroxysmal complete heart block, which required cardio-pulmonary resuscitation, treated by a temporary pacing, and shortly after, a permanent pacemaker was implanted. On a chest X-ray, CT and Gallium-scan, there was evidence of hilar and axillar lymphadenopathy. The diagnosis of sarcoidosis was confirmed by a mediastinal lymph node biopsy. Patient 2 was a 58-year-old female, followed for hyperlipidemia and pulmonic Sarcoidosis (presented 2 years earlier by cough and dyspnea) and was proven by a CT scan (demonstrating enlarged mediastinal lymph-nodes) and by mediastinal lymph node biopsy. The patient presented a month earlier with fatigue, dizziness and almost syncope, and evidence of a high degree atrio-ventricular (AV) block (with no evidence of cardiac ischemia), treated by a permanent pacemaker implantation. Prior to the implantation, there was no evidence of inducible tachyarrhythmia on an electro-physiological-study (EPS). Conclusions. We present two patients with cardiac sarcoidosis presenting with high-degree AV block, who needed a pacemaker therapy. One was known as suffering from pulmonary sarcoidosis, and in the second case, the diagnosis was established during the recent event. Our case reports aim to increase awareness on cardiac sarcoidosis as a possible cause of syncope and sometimes of cardiac arrest. It is recommended by us and other investigators to follow patients with sarcoidosis for early screening for cardiac involvement (by detailed clinical history), a 12-lead ECG and even echocardiogram, and when needed other modalities, and thus save lives.

Techniques and tools

14–8 Abstract 01–17

110 THE SIGNIFICANCE OF HEART RATE TURBULENCE MEASUREMENT IN OLDER MEN WITH HIGH CARDIOVASCULAR RISK.

Elisaveta Guliaeva¹

¹ Kemerovo medical academy, Kemerovo, Russia

The purpose of the present study was to examine indicators of heart rate turbulence on this 24-h ECG in older men suffering from essential arterial hypertension (AH) with high cardiovascular risk. Materials and methods. The group surveyed was consisted of 75 men with arterial hypertension of degree III, risk 4, in middle age 67.4 ± 2.5 years. AG diagnostics was carried out taking into account the recommendations of the RSC (Russian Society of Cardiology) (2010). All patients were evaluated for quality of life (GL) on the scale of the SF-36. The assessments of the level of depression by Beck questionnaire and of reactive and personal anxiety on the evaluation scale of Ch. Spilbergera and Y.l. Hanina had place. A 6-min walk test, the study of biological age by V.P. Voitenko method as well as ECG, echocardiography, a daily monitoring of ECG in order to evaluate the heart rate variability and study of heart rate turbulence with an assessment of turbulence onset (TO) and turbulence slope (TS) according to the 24-h ECG monitoring were performed. The comparison group was consisted of 25 male with AG at the age of 46.3 ± 3.8 years. It was found that elderly patients with high cardiovascular risk differ from the patients of the comparison group by an increased performance of TO and decrease of TS (P < 0.05). Pathological night values of TO was associated with a reliable (P < 0.05) increase in body mass index (BMI), the average heart rate (AHR), the reduction of circadian index, decreased power of the low- and high-frequency components of heart rate variability spectrum, elongation QT according to standard ECG, an increase of the minute bloodstream (IOC) and the index of left ventricular myocardium mass (iLVMM). An equation of multifactor regression analysis including 12 parameters of clinical-functional status of elderly patients as independent variables found the influence of independent myocardial mass index of left ventricle of the heart on the night TO reducing. Conclusion. Analysis of heart rate turbulence in older patients with AG is useful for clarifying the severity of their clinical status and can be used in the cardiovascular risk stratification.

14–9 Abstract 18–13

111 PHYSICS OF RADIOFREQUENCY ABLATION IN-VITRO TEACHING SYSTEM FOR PHYSICIANS AND MEDICAL ENGINEERING STUDENTS

Tobias Haber¹, Gennadie Kleister¹, Burcu Selman¹, Johannes Härtig², Juraj Melichercik², Bruno Ismer¹

¹ Peter Osypka Institute for Pacing and Ablation, Offenburg, Germany; ² MediClin Heart Center Lahr/Baden, Lahr, Germany

Radiofrequency (RF) ablation is the most popular method in the treatment of supraventricular re-entrant and focal tachycardias, atrial fibrillation and an increasing number of ventricular tachycardias. It is utilized by computer-controlled application of RF current. Nevertheless, despite lots of developments in the last years, RF ablation is still a complex procedure requiring the physician’s electrophysiological experience and expertise, as well as physical science basics knowledge. Thus, there is a need of in vitro essays to explain several effects observed during clinical application. Aims: The study aims to create an in-vitro RF ablation teaching system in order to school physicians and medical engineering students the physical science basics of radiofrequency catheter ablation. Methods: To enable in vitro RF ablation experiments on pork in small groups, six workstations were equipped with computer-controlled RF ablation generators. A connection box was prepared to allow ablations with catheters of different make and model. Special wetlab was established combining a basin containing physiological saline solution with a thermostat and a pump to simulate an adjustable blood flow. Screenshot software was installed to document the graphical trends of temperature, power and impedance. Any workstation’s screen can also be displayed on additional large-scale monitors for discussions of the observed effects. Results: The RF ablation teaching system was successfully used to demonstrate the differences in lesion size and geometry between standard 4- and 8-mm-tip electrodes with single or dual sensor technology. Effects of larger and deeper lesion size were studied using open and closed irrigated RF ablation. Furthermore, prevention of pops and the influences of blood flow as well as position of tip electrode with a specific angle to the myocardium could be clearly demonstrated. Conclusions: In several workshops, the in vitro teaching system provided excellent requirements for both physicians and medical engineering students, to become acquainted with the physical science basics of RF catheter ablation.

14–10 Abstract 04–11

112 IMPAIRED ADAPTATION OF WHOLE HEART ACTION POTENTIAL DURATION IN RESPONSE TO PHYSIOLOGICAL AUTONOMIC STRESS IN BRUGADA SYNDROME.

Kevin Ming Wei Leong¹, Fu Siong Ng¹, Caroline Roney¹, Phang Boon Lim¹, Sian E Harding¹, Nicholas S Peters¹, Amanda Varnava¹, Prapa Kanagaratnam¹

¹ NHLI, Imperial College London, London, UK

Introduction: Sudden death in Brugada syndrome (BrS) is associated with rest, when parasympathetic tone predominates and/or sympathetic tone is diminished. Using non-invasive electrocardiographical imaging (ECGi) with a vest, this pilot study aims to characterise the electrophysiological substrate in BrS patients during different states of autonomic stress. Methods: The ECGi vest projects patients’ reconstructed electrograms (EGMs) onto an image of their own heart geometry. This was applied to eight patients (four BrS, four controls; mean age 40.5 years; six males) during rest, treadmill and tilt table testing. Activation recovery interval (ARI), an action potential duration surrogate, of the epicardial EGM was taken from right and left apical, mid and basal regions from each individual and corrected for heart rate (cARI). Results: Baseline cARI was not significantly different in both groups (299 ± 17 ms vs 284 ± 18 ms; p = ns) (Graph 1). There was appropriate shortening of cARI (299 ± 17 msec to 258 ± 22 msec; p = 0.006) from baseline to peak exertion, and prolongation on recovery (258 ± 22 ms to 296 ± 23 ms; p = 0.03) in the control group, but not in the BrS group. With upright tilt, a significant increase in cARI was noted in the control group by 5 and 20 min (p < 0.05). A smaller rise was seen in the BrS group with a significant rise noted later at 20 min (p = 0.04). These results suggest BrS patients have an impaired response to physiological sympathetic stressors. Conclusion: This study shows how cARI alters with various autonomic stresses in normal and BrS patients. Its findings suggest individuals with BrS have impaired sympathetic autonomic function which may contribute to arrhythmogenesis.

14–11 Abstract 03–10

113 LACK OF ATORVASTATIN PROTECTIVE EFFECT AGAINST ATRIAL FIBRILLATION IN B2B2 CETP GENOTYPE

Francesca Galati¹, Antonio Galati², Serafina Massari¹

¹ DiSTeBA, University of Salento, Lecce, Italy; ² Division of Cardiology, Card. G. Panico Hospital, Tricase, Italy

Introduction. There has been some evidence for a role of statins in reducing the risk of atrial fibrillation (AF), but the response to statin treatment varies considerably due to environmental and genetic factors. One of these is related to CETP expression. So, we assessed whether CETP TaqIB polymorphism influences AF occurrence after treatment with statins. Methods. Two hundred unrelated dyslipidemic Caucasian patients (100 men and 100 women; mean age 75 ± 8) from Salento (Southern Italy) were enrolled and assigned to atorvastatin treatment. All patients were followed at 6-month intervals. CETP TaqIB polymorphism was genotyped by RFLP-PCR. Results. During a mean follow-up time of 47 ± 6 months, 73 patients (36.5 %) experienced at least one episode of AF, while the remaining 127 patients (63.5 %) were free of AF episodes. No significant differences were observed between the two groups with regard to demographic, clinical and echocardiographic data, as also regarding the values of lipid parameters before and after statin therapy. B2B2 genotype was associated to higher AF frequency (27 patients 37 % vs 6 patients 5 %), while B1-carriers had lower AF incidence (46 patients 63 % vs 121 patients 95 %); this difference was statistically significant (p < 0.0001).

	AF	not AF
B2B2	27 (37 %)	6 (5 %)
B1B2	17 (23 %)	80 (63 %)
B1B1	29 (40 %)	41 (32 %)

Conclusions. Because statins reduce CETP activity up to 30 %, we hypothesize that such CETP activity reduction by statins, in patients with low CETP levels induced by polymorphism, may counteract the beneficial effect of statins on AF.

14–12 Abstract 04–12

114 WHOLE HEART ACTIVATION PATTERNS DURING PHYSIOLOGICAL STRESS IN BRUGADA SYNDROME.

Kevin Ming Wei Leong¹, Fu Siong Ng¹, Caroline Roney¹, Phang Boon Lim¹, Sian E Harding¹, Nicholas S Peters¹, Amanda Varnava¹, Prapa Kanagaratnam¹

¹ NHLI, Imperial College London, London, UK

Introduction: Non-invasive electrocardiographical imaging (ECGi) reconstructs epicardial electrograms from body surface potentials collected from 250 electrode vest and displays the activation on a 3D cardiac image segmented from a chest CT. This enables whole heart activation to be studied in vivo under different physiological situations. We hypothesised that conduction patterns are abnormal in patients with Brugada syndrome (BrS) during various states of autonomic stress. Methods: Eight patients who were planned EP studies were recruited (four BrS, four controls; mean age 40.5 years; six males). Activation was recorded with the patients wearing an ECVue™ vest and ECGi maps were derived from a single cardiac cycles during rest, immediate recovery after peak exertion following an exercise treadmill and 5 min into an upright tilt test. Results: Although there was variability in ventricular activation patterns between individuals, some general patterns could be observed. In both groups, the left ventricle had a later activation time (AT) than the right ventricle during rest and exercise and with upright posturing. ATs of the left ventricle (LV) and right ventricle (RV) were noted to become closer during exercise as well. At baseline, ATs in the RVOT and RV were similar for all. The main difference noted between the groups was during exercise recovery, when AT in the RVOT was more delayed than the RV in three out of four BrS patients but only one out of four of the controls. Figure 1 provides an illustrative example of the findings. Conclusion: We demonstrate the feasibility of measuring physiological activation patterns during autonomic stress using the ECGi system. During recovery from exercise, activation delay in the RVOT is noted more frequently in the BrS group.

14–13 Abstract 04–14

115 ELECTROPHYSIOLOGICAL RESPONSES TO AUTONOMIC STIMULATION ARE BLUNTED IN A MURINE MODEL OF BRUGADA SYNDROME

Malcolm Finlay¹, Vishal Vyas², Alastair Yeoh¹, Stephen Harmer³, Christopher Huang⁴, Pier Lambiase⁵, Andrew Tinker³

¹ Barts Health NHS Trust and QMUL, London, UK; ² UCL and QMUL, London, UK; ³ Queen Mary University of London, London, UK, ⁴ Cambridge University, Cambridge, UK; ⁵ UCL, London, UK

INTRODUCTION. Autonomic stimuli are often identified as precipitants of clinical arrhythmia in Brugada syndrome. This has been attributed to either abnormal electrophysiological modulation by autonomic stimuli or to primary abnormalities in cardiac neuronal innervation. We use a heterozygotic SCN5a+/− murine tissue-slice model to test these hypotheses. METHODS. Two hundred-micrometer-thin ventricular slices were cut from 3-month-old murine SCN5a+/− hearts (HET) and littermate controls (WT) following pre-treatment with cardioplegic solution via Langendorff perfusion. Slices were superfused on an 8 × 8 microelectrode array (MEA2100, MultiChannel Systems, panel A), and stimulated externally in a decremental S1S2 protocol. Conduction velocity was calculated using a gradient of activation times. Values are given as mean ± standard error. RESULTS. HET myocardium had a lower conduction velocity (0.31 ± 0.04 vs 0.51 ± 0.14 ms⁻¹), higher thresholds (4.0 ± 0.7 vs 2.7 ± 0.4 V) and longer effective refractory periods (ERP 79 ± 4 vs 63 ± 3 ms, p < 0.001) than controls. A blunted response to 10 nM isoprenaline (Iso) was observed in SCN5a tissue, with only a 10 % increase in conduction velocity (c.f. 31 % increase in controls, p = 0.02, panel B). Decreased in ERP with Iso was smaller in HETs than WTs (ERP with Iso 73 ± 1 vs 51 ± 7 ms). Carbachol restored conduction velocities towards baseline without lengthening ERP in WT. Iso reduced thresholds in WT significantly more than in HET samples (3.9 ± 0.9 vs 1.9 ± 0.4 V, p < 0.001). CONCLUSION. SCN5a +/− murine myocardium fails to increase excitability in response to sympathetic stimuli. This demonstrates a mechanism by which autonomic state may accentuate predisposition to arrhythmia in sodium channel disease.

14–14 Abstract 05–12

116 THE LASER DOPPLER VIBROMETRY: A NON-CONTACT TECHNIQUE FOR HEART RHYTHM MONITORING

Armin Luik¹, Laura Mignanelli², Kristian Kroschel³, Claus Schmitt¹, Lorenzo Scalise², Christian Rembe⁴

¹ Staedtisches Klinikum Karlsruhe, Karlsruhe, Germany; ² Università Politecnica delle Marche, Ancona, Italy; ³ Fraunhofer Institut IOSB, Karlsruhe, Germany; ⁴ Polytech, Waldbronn, Germany

Background: Monitoring of the heart’s rhythm is the cornerstone of the diagnosis of cardiac arrhythmias. The current technologies are all based on the electrocardiogram (ECG). Major limitation of the ECG is the need of special electrodes attached to the body. We introduce a new technique which allows a non-contact registration of the heart rhythm. The laser Doppler vibrometry (LDV) is a non-contact interferometric technique which is capable to detect smallest vibrations of, i.e., the skin. Recording the vibrations of the heart’s contractions is called vibrocardiography (VCG). This technique enables a non-contact registration of the heart rate due to the vibrations on the skin caused by the contracting ventricles. A reliable detection of the heart rate has already been shown. However, a complete patient monitor requires both, a reliable detection of the ventricular and atrial contraction. The aim of this study was to evaluate whether the VCG allows a reliable detection of the atrial contraction and the different degrees of AV-blocks. Methods: 13P were analyzed. The ECG and VCG were recorded simultaneously. The infrared laser LDV was positioned in 1-m distance from the measurement point. The best measurement location was defined by echocardiography. In the pacemaker patients, the pacemaker was temporarily inhibited to reveal a higher degree AV-block. The equivalent of the PR interval was analyzed and the accuracy calculated. In addition, in two subjects, the feasibility to acquire a VCG signal through a cotton shirt was evaluated. Results: A reliable VCG signal could be recorded in all subjects and patients. The induced third-degree AV blocks in the pacemaker patients showed in the VCG a clear atrial and ventricular signature. The M-wave was traceable even during sinus rhythm or fusion beats. To prove the reliability of the PR interval of the VCG, 20 repetitive heart beats of every subject were analyzed. The PR interval of the VCG could be determined with an uncertainty of 13.6 ± 6.5 ms. Although the VCG through the cotton shirt was lower in amplitude, it presented with the equivalent information. Conclusion: The VCG recorded from a thoracic point enables a reliable non-contact monitoring of the heart rhythm. The PR interval can be detected with an accuracy of >90 % which allows a reliable detection of AV block of all degrees. The VCG signal can be recorded even through a cotton shirt. Therefore, the IR-LDV technology suits well for routine clinical applications.

14–15 Abstract 05–14

117 SENSITIVITY OF OPTICAL MAPPING PHASE DYNAMICS TO POST-PROCESSING PARAMETERS INCLUDING LOW-PASS FILTER CUTOFF FREQUENCY AND SPATIAL BINNING

Caroline H Roney¹, Chris D Cantwell¹, Michael T Debney¹, Norman A Qureshi¹, Prapa Kanagaratnam¹, Jennifer H Siggers¹, Nicholas S Peters¹, Fu Siong Ng¹

¹ Imperial College London, London, UK

Introduction: During fibrillation, the observed activation patterns depend critically on the post-processing techniques applied. In this study, we examined the sensitivity of wavefront dynamics observed in optical mapping data to the choice of filtering and post-processing parameters used. Methods: Complex arrhythmia wavefront dynamics were analysed for an optically mapped canine cholinergic atrial fibrillation preparation. The following parameters were varied, either individually or in combination: spatial bin size for voltage, low-pass filter, and spatial bin size for phase. The following were calculated: dominant frequency (DF), number of phase singularities (PSs) by duration, spatial distribution, maximum duration, and mean duration of PSs. Results: Low-pass filtering at 100 % of DF removed physiological frequencies, whilst 200 % resulted in more PSs and a decrease in the ability of the algorithm to track longer lasting PSs. For filter choices of 125–175 % of DF, heat maps correlated well (r > 0.8). Voltage and phase bin sizes had a larger effect than filter settings on the number of PSs (Fig) and were not independent; binning each at 5 × 5 led to a larger number of PSs than at 9 × 9 (13.9 vs 5.5 per frame), which were short lived (1.2 vs 1.4 per frame >50 ms). Bin sizes of 9 × 9 were found to be sufficient to identify true PSs, without over-smoothing the data. Mean duration increased for larger bin sizes as PSs became easier to track (17.3 ± 16.6 vs 20.8 ± 19.5 ms, 5 × 5 vs 9 × 9). Conclusion: The total number of PSs was most affected by changes in spatial binning of voltage and phase, with an increase in false-positive PSs for small bin sizes, which reduces the ability of the algorithm to track PSs faithfully. DF maps were more affected by filter settings than by voltage bin size. These findings indicate that careful consideration is required for choice of post-processing parameters.

14–16 Abstract 28–10

118 FIRST APPLICATION OF A NOVEL, MULTI-SITE, HIGH-RESOLUTION EPICARDIAL, MAPPING APPROACH

Natasja de Groot¹, Ameeta Yaksh¹, Charles Kik¹, Paul Knops¹, Frans Oei¹, Pieter van de Woestijne¹, Maurits Allessie¹, Ad Bogers¹

¹ Erasmus Medical Center, Rotterdam, Netherlands

Background: Based on the premise that atrial fibrillation (AF) can be eliminated by ablation of either the trigger or the substrate perpetuating AF, it is expected that multi-site high-density mapping is a suitable tool to diagnose AF thereby allowing individualization of AF treatment. The goal of this study was to assess the feasibility and safety of a new high-resolution epicardial mapping approach of the entire atria for assessment of the degree and extension of electropathology as a routine procedure during cardiac surgery. Methods: Epicardial mapping (128/192 electrodes; inter-electrode distance 2 mm) was performed in 291 patients (218 male, age 66 ± 11 years) undergoing elective surgery during sinus rhythm (SR) and (induced) AF. A temporary bipolar epicardial pacemaker wire stitched to the right atrial free wall served as a temporal reference electrode and a steal wire fixed to subcutaneous tissue of the thoracic cavity as an indifferent electrode. Fixed rate pacing at the right atrial free wall was applied on a different temporary bipolar pacing wire in order to induce AF. Total duration of the mapping procedure was defined as time between onset of the preparation process until the end of the last recording. Electro-physiological parameters within mapping quadrants covering the entire atrial epicardial surface were quantified and designated to anatomical quadrants of 1 cm². Results: Total mapping time during SR or AF was, respectively, 3 ± 1 and 4 ± 2 min. Hemodynamic parameters (mean arterial pressure (MAP), right atrial pressure (RA), BIS score, ST-T segment alterations) before and during SR mapping were comparable (P < 0.22). During AF, only MAP (71 ± 11 vs 67 ± 10 mmHg (p < 0.004)) and RA (10 ± 4 vs 11 ± 4 mmHg (p < 0.0001)) decreased. Beat-to-beat variation of SR cycle length and peak-to-peak amplitude of unipolar potentials was, respectively, 0.04 ± 14.42 ms and −0.01 ± 0.53 mV, reflecting stability of the mapping array. Complications were not observed. Conclusion: our novel intra-operative epicardial atrial mapping approach allows determination of the degree and extension of electropathology and can be safely applied during both SR and AF. This mapping approach is the first technique allowing identification of the arrhythmogenic substrate in the individual patient thereby taking the first step towards personalizing treatment of AF.

Poster session B part 2

Sunday, April 19, 2015

Posters exposed from 02:00 PM to 05:00 PM

Presenters and chairpersons present from 03:30 PM to 5:00 PM

05:30 PM Atrial fibrillation ablation

14–17 Abstract 15–39

119 SIMULTANEOUS PULMONARY VEIN CRYOABLATION AND CAVOTRICUSPID ISTHMUS RADIOFREQUENCY ABLATION IN PATIENTS WITH COMBINED ATRIAL FIBRILLATION AND TYPICAL ATRIAL FLUTTER

Michael Peyrol¹, Pascal Sbragia¹, Thibault Ronchard¹, Jennifer Cautela¹, Chloé Villacampa¹, Marc Laine¹, Laurent Bonello¹, Franck Thuny¹, Franck Paganelli¹, Samuel Lévy²

¹ CHU Nord, Marseille, France; ² Aix-Marseille Université, Marseille, France

Purpose—Pulmonary vein isolation (PVI) using cryoballoon (CB) technique and cavotricuspid isthmus (CTI) ablation using radiofrequency (RF) are established interventions for the management of paroxysmal drug-resistant atrial fibrillation (AF) and typical atrial flutter (AFL). Whether simultaneous delivery of cryoenergy at the PVs using the CB technique and RF energy at the CTI is feasible and safe is still to be demonstrated. Methods—Consecutive patients with combined paroxysmal AF and typical AFL were prospectively included in the present study and underwent simultaneous delivery of RF energy at the CTI during CB applications at the PVs ostia. Results—Twelve patients (men = 10, women = 2) with a mean age of 62 ± 12 years (range 42 to 80 years) were included in this study. Pulmonary vein isolation was successfully achieved in all 48 treated PVs and sustained bidirectional CTI conduction block obtained in all patients. Mean number of cryoapplications per patient was 8.2 ± 0.6 (range 8 to 10). Mean procedure duration and radioscopy exposure were 82 ± 29 min (range 60 to 165 min) and 22 ± 7 min (range 12 to 31 min), respectively. The reported ablation protocol of combined paroxysmal AF and typical AFL did not result in prolongation of the procedure duration or in prolonged radiation exposure when compared to CB-PVI alone. No interferences between both ablation energy systems were observed. Conclusions—These preliminary results suggest that combined paroxysmal AF and typical AFL can be successfully and safely ablated using hybrid energy sources with simultaneous CTI ablation using RF during CB applications at the PV ostia. PV pulmonary vein, CB cryoballoon, CTI cavotricuspid isthmus, RF radiofrequency, LA left atrium

	PV-CB ablation/CTI RF	PV-CB ablation	p value
Age (years)	62 ± 12	61 ± 11	0.79
LA diameter (mm)	41 ± 6	40 ± 5	0.94
Procedure duration (min)	82 ± 29	79 ± 24	0.76
Radiation exposure (min)	22 ± 7	20 ± 10	0.51
Nb. of CB applications	8.2 ± 0.6	8.4 ± 1.0	0.65

14–18 Abstract 15–30

120 FEASIBILITY AND SAFETY OF NURSE-DIRECTED DEEP SEDATION

Laura Varotto¹, Mehdi Namdar¹, François Mattey-Prévot¹, Jacques Lyvet¹, Dominique Marcelot¹, Alain-Stéphane Eichenberger¹, Pascale Gentil-Baron¹, Henri Sunthorn¹, Haran Burri¹, Dipen Shah¹

¹ Hôpitaux Universitaires de Genève, Service de Cardiologie, Geneva, Switzerland, Geneva, Switzerland

Introduction: Benzodiazepines and opiate boluses are currently widely used for catheter ablation of atrial fibrillation (AF). However, patient comfort, compliance and prolonged immobility are difficult to manage with conscious sedation. Therefore, we aimed to determine the feasibility and safety of deep sedation with propofol/fentanyl infusion directed by specialized nurses in patients undergoing an AF ablation procedure. Methods: Three nurses of our catheterization laboratory completed training for inducing and managing deep sedation under supervision of experienced anesthesiologists in patients undergoing AF ablation procedures. The training included a theoretical knowledge base (4 × 2 h) and a practical part (2 h) using a simulator for ventilator and basic life support and finally a practical exam during an ablation procedure, after which the nurses were institutionally certified to manage deep sedation without ventilatory support in selected low-risk (ASA classes I and II) patients undergoing AF ablation procedures with supervision of the operator, if needed. After an iv propofol bolus, maintenance of sedation was achieved with continuous iv administration of propofol. Heart rate, arterial blood pressure, and oxygenation were continuously monitored. Feasibility and safety aspects of this approach were analyzed and scores (0–10) for pain, patient and operator satisfaction were assessed after the procedure. Results: A total of 68 consecutive patients (55 ± 13 years, range 18–76 years) were included in this analysis. Mean total sedation time was 179 ± 55 min (range 45–300 min), mean total administered dosages of propofol and fentanyl 281 ± 140 mg (range 0–680 mg) and 273 ± 93 μg (range 75–650 μg), respectively. Mean scores for pain, patient and operator satisfaction were 5.5 ± 2 (range 0–10), 9.1 ± 0.9 (range 5–10) and 9.1 ± 0.7 (range 7–10), respectively. No correlations were found between the assessed parameters. No sedation-related complications occurred during the procedures, minor incidents without the need of further anesthesiologic interventions included nausea (×1), apnea >10 s, but <30 s (×2), oxygen desaturation <95 % <30 s (×2) and hypotension corrected by minor doses of vasopressors (×2). Conclusion: Deep sedation without assisted ventilation directed by specialized nurses for AF ablation procedures in selected low-risk patients is feasible and safe; results in excellent patient and operator satisfaction and should be more widely used.

14–19 Abstract 15–31

121 MINIMALLY INVASIVE SURGICAL ABLATION FOR STAND-ALONE ATRIAL FIBRILLATION IS ASSOCIATED WITH EXCELLENT OUTCOMES AT LONG-TERM FOLLOW-UP

Gianluigi Bisleri¹, Fabrizio Rosati¹, Lorenzo Di Bacco¹, Claudio Muneretto¹

¹ University of Brescia Medica School, Brescia, Italy

Background: Minimally invasive surgical treatment of atrial fibrillation (AF) has gained popularity during the past decade; however, there is paucity of data about the long-term outcomes of this novel approach. Methods: Study population included 125 consecutive patients undergoing stand-alone surgical treatment of atrial fibrillation via a closed-chest, right-sided monolateral thoracoscopic approach (box lesion set) by means of a versapolar (combining uni/bipolar) radiofrequency ablation device. Mean age was 62.5 ± 10.4 years, and the prevalence of paroxysmal, persistent and long-standing (LS-persistent) AF was 37.6, 11.2 and 51.2 %, respectively, with a median AF duration of 60 months. Mean left atrial antero-posterior diameter was 48.6 ± 8.6 mm. Results: The procedure was successfully accomplished via an endoscopic approach in all patients except one requiring conversion to mini-sternotomy. Hospital mortality was 0 % and no major complications occurred during the post-operative hospital stay except for a thromboembolic event occurring in 2 patients (1.6 %). Multivariate Cox regression analysis identified long-standing persistent AF (OR 9.5; CI = 2.5–35.4; p = 0.001) and female gender (OR 3.03; CI = 1.06–8.7; p = 0.039) as independent risk factors for AF recurrence; instead, paroxysmal AF was associated with improved rhythm outcomes (OR 0.12; CI = 0.04–0.36; p < 0.001). At a median follow-up of 60 months, overall stable sinus rhythm was achieved in 79.2 % (99/125 patients) (paroxysmal 91.5 %, 43/47 patients; persistent: 78.6 %, 11/14 patients; LS-persistent: 70.3 %, 45/64 patients); Finally, there was a trend towards the stabilization of rhythm over the follow-up time, as depicted by Spearman analysis showing a positive correlation among sinus rhythm restoration and follow-up duration (rho = 0.82). Conclusion: Totally endoscopic AF surgical ablation (box lesion) is a safe and effective procedure providing excellent and stable results over time at long-term follow-up. Rhythm outcomes in patients with LS-persistent AF may be further improved with an integrated hybrid approach.

14–20 Abstract 15–14

122 TIME COURSE OF LUMINAL ESOPHAGEAL TEMPERATURE DURING SECOND-GENERATION CRYOBALLOON ABLATION: COMPARISON OF THE 23- AND 28-MM BALLOON

Benedikt Bunz¹, Florian Straube¹, Uwe Dorwarth¹, Martin Schmidt¹, Michael Wankerl¹, Stephen Howard², Stefan Hartl¹, Hans Ullrich Ebersberger¹, Ellen Hoffmann¹

¹ Department of Cardiology and Internal Intensive Care Medicine, Heart Center Munich-Bogenhausen, Munich Municipal Hospital Group, Munich, Germany; ² Medtronic Inc., Mounds View, MN, USA

Background: Second-generation cryoballoon (CB) ablation attains high rates of acute pulmonary vein isolation (PVI) within a significantly faster and less complex procedure compared to first-generation CB. Thermal esophageal lesions were reported with the 28-mm CB. Currently, there exist no data concerning the time course of luminal esophageal temperature (LET) comparing the 23- and 28-mm CB. The aim of this prospective, observational study is to determine the differences between the 23- and 28-mm CB regarding the LET during CB ablation. Methods: Thirty consecutive patients with paroxysmal or persistent atrial fibrillation underwent CB PVI. The 28-mm, 23-mm, or both balloons were applied with respect to the LA/PV-anatomy as determined by pre-procedural cardiac imaging. Standard freezing time was 180 s with an additional bonus freeze after PVI. LET was continuously recorded during the whole procedure. Pre-specified cutoff value for premature termination of a cryoapplication was a LET ≦ + 15 °C. Esophagoscopy was planned in case of symptoms suggestive for esophageal lesions. Results: In total, 395 freeze cycles were applied in 125 veins, 149 (38.0 %) with the 23 mm and 246 (62.0 %) with the 28 mm CB. PVI was achieved in 100 % of the veins. Premature termination of the freeze cycle because of low LET occurred only during ablation of the inferior pulmonary veins. None of the patients developed symptomatic esophageal lesions. Minimal LET (median) was 35.3 (14.2–36.4) °C with the 23-mm CB and 35.4 (12.8–36.7) °C with the 28-mm CB, p = 0.30. In subgroup analysis of the pulmonary veins, there was no significant difference either. The freeze time after which LET started to drop showed a positive correlation to minimal LET, p = 0.001. LET drop within ≦25 s predicted a LET ≦ + 15 °C with the highest sensitivity (83 %) and specificity (92 %) in ROC curve analysis. Conclusion: Low LET ≦ + 15 °C occurred rarely with both balloon sizes and was without statistical significance. Moreover, no symptomatic esophageal lesions were reported. CB ablation following an individualized anatomic approach seems to be equally safe with either the 23- or the 28-mm CB concerning the LET. LET drop within ≦25 s predicts a minimal LET ≦ + 15 °C with a high sensitivity and specificity.

14–21 Abstract 15–10

123 HIGH LEFT ATRIAL PRESSURES ARE ASSOCIATED WITH ADVANCED ELECTROANATOMICAL REMODELING OF LEFT ATRIUM AND INDEPENDENT PREDICTORS FOR CLINICAL RECURRENCE OF ATRIAL FIBRILLATION AFTER CATHETER ABLATION

Junbeom Park¹, Boyoung Joung¹, Jae-Sun Uhm¹, Chi Young Shim¹, Moon Hyoung Lee¹, Hui-Nam Pak¹

¹ Yonsei University Health System, Seoul, Republic of Korea

Background: The clinical significance of left atrial pressure (LAP) has not yet been clearly elucidated in patients with atrial fibrillation (AF). Objective: The purpose of this study was to explore the effects of elevated LAP on pathophysiology and clinical outcome after radiofrequency catheter ablation (RFCA) in patients with AF. Methods: We measured LAP during both sinus rhythm (SR) and AF in 454 patients (76.7 % male, 58 ± 11 years old, 71.8 % paroxysmal AF) who underwent RFCA, and compared LAPv-wave (LAPpeak) and LAPy-wave (LAPnadir) with imaging (echocardiography and CT), electrophysiologic mapping (NavX), and clinical data. In 280 patients, pulmonary vein (PV) diastolic flow velocity was measured during SR by trans-esophageal echocardiography. Results: 1. Patients with LAPpeak (SR) ≥19 mmHg had greater LA dimension (p < 0.001), LA volume index (p = 0.003), and E/Em (p = 0.001), and reduced LA voltage (p < 0.001) and S’ (p = 0.006) compared to those with low LAPpeak (SR). 2. High LAPpeak (SR) was an independently associated with anterior LA volume (B = 0.381, 95 %CI 0.169∼0.593, p < 0.001) and low LA voltage (B = −0.022, 95 %CI −0.030∼−0.013, p < 0.001). 3. PV diastolic flow velocity (B = 0.161, 95 %CI 0.083∼0.239, p < 0.001) and E/Em (B = 0.430, 95 %CI 0.096∼0.763, p = 0.012) were independent, non-invasive parameters associated with high LApeak(SR). 4. During 13.1 ± 6.0 months of follow-up, high LAPpeak(SR) was an independent predictor for clinical recurrence of AF (HR 1.887, 95 %CI 1.063∼3.350, p = 0.028). Conclusions: Elevated LAP was closely associated with electroanatomical remodeling of the LA and was an independent predictor for recurrence after AF ablation. PV diastolic flow velocity and E/Em can be utilized as a non-invasive parameter predicting high LAPpeak(SR) in patients with AF.

14–22 Abstract 18–24

124 ASSESSMENT OF BMI AND HEMODYNAMIC PARAMETERS IN AF PATIENTS UNDERGOING PULMONARY VEIN ISOLATION PROCEDURES—POTENTIAL IMPACT ON PROCEDURAL PARAMETERS AND AF RECURRENCE

Johannes Siebermair¹, Stefan Sattler¹, Eva Klocker¹, Lucia Olesch¹, Samira Saraj¹, Ina Klier¹, Christoph Schuhmann¹, Sebastian Clauss¹, Moritz Sinner¹, Stefanie Fichtner¹, Stefan Kääb¹, Heidi L. Estner¹, Reza Wakili¹

¹ Medical Department I, KlinikumGrosshadern Munich, University of Munich, Munich, Germany

INTRODUCTION: Pulmonary vein isolation (PVI) is an established therapy option for atrial fibrillation (AF) treatment. Hemodynamic parameters and body mass index (BMI) have recently been investigated in these patients in regard to potential impact on electrophysiological properties. The objective of this study was to assess hemodynamic parameters, BMI, procedural parameters of patients undergoing PVI for AF treatment to evaluate potential correlations to procedural parameters and clinical outcome. METHODS: We studied a cohort of 302 patients undergoing PVI for treatment of AF (141/302 paroxysmal AF, 161/302 persistent AF, mean age 63 ± 11) over a mean follow-up (FU) period of 254 ± 178 days. Left atrial (LA) diameter, left ventricular end-diastolic pressure (LVEDP) and LA pressure were measured invasively prior to ablation. In addition, total procedure time, cumulative radiation dose and body mass index (BMI) were assessed. Clinical outcome (freedom from AF) was determined 3, 6 and 12 months post PVI by interview and 7d Holter ECG. RESULTS: Our analysis revealed significant higher LA diameter and LA pressure values in patients with persistent AF vs. paroxysmal AF (median LA 40 mm [29;64], LA pressure 16 mmHg [5;32] in paroxysmal, and median LA 42 mm [20;57], LA pressure 18 mmHg [5;40], respectively). LA pressure was independently associated with LA diameter and cumulative radiation dose (r = 0.183/p < 0.029 and r = 0.266/p < 0.005, respectively). Furthermore, BMI showed a correlation to LVEDP and LA pressure prior ablation (r = 0.176, p < 0.05 and r = 0.275, p < 0.005, respectively). BMI per se was significantly positively correlated with longer cumulative procedure time (p = 0.029), while BMI > 26 kg/m² and persistent AF and were independently predictors of longer cumulative procedure times (p = 0.03 and p = 0.01, respectively). Interestingly, only elevated LA pressures >17 mmHg (median) during PVI were associated with an impaired clinical outcome with respect to freedom from AF during FU (low LA pressure 77 % vs. high LA pressure 52 %, respectively). However, BMI and other hemodynamic parametersdid not show any positive correlation in regard to AF recurrence. CONCLUSION: LA diameter and LA pressure are elevated in patients with persistent AF. BMI > 26 and persistent AF seem to be predictive in regard to procedural complexity, however without prediction on short-term ablation outcome in the studied collective. LA pressure was the only parameter being predictive for mid-term clinical outcome after PVI. Further studies are required to elucidate the potential value of hemodynamic parameters and BMI in defining treatment strategies for AF patients.

14–23 Abstract 18–15

125 LONG-TERM EFFICACY OF PULMONARY VEIN ANTRUM ISOLATION ALONE IN ATRIAL FIBRILLATION ABLATION, A SINGLE CENTER COHORT STUDY.

Cas Teunissen¹, Jeroen vd Heijden¹, Rutger Hassink¹, Wil Kassenberg¹, Rolf Brummel¹, Peter Loh¹

¹ Utrecht Medical Center Utrecht, Utrecht, Netherlands

Introduction: Pulmonary vein antrum isolation (PVAI) is a well-established treatment option in patients with symptomatic, drug refractory atrial fibrillation (AF). There is an ongoing discussion on whether and when to add substrate modification to PVAI, especially in (longstanding) persistent AF. Long-term follow-up studies of PVAI alone as a primary ablation strategy are limited. Objectives: The study aims to evaluate the long-term efficacy of PVAI alone as a primary ablation strategy in all patients independently from the nature of AF and to assess predictors of arrhythmia recurrence. Methods: From January 2005 to March 2011, 509 consecutive patients (mean age 57 years, 61.1 % paroxysmal AF, 25.5 % persistent AF and 13.4 % longstanding persistent AF) suffering from symptomatic, drug refractory AF underwent PVAI in the University Medical Center Utrecht. In redo procedures, pulmonary veins (PVs) were checked for reconnection. In case of PV reconnection, ablation was restricted to re-PV isolation without substrate modification. If the PVs were found to be isolated, substrate modification was performed. The mean follow-up duration after the first and last ablation was, respectively, 66 and 55 months. Results: In total, 774 procedures were performed. After a single procedure, PVAI was sufficient in restoring and maintaining sinus rhythm in 41.3 % (n = 210). Success increased to 62.5 % (n = 318) after multiple procedures (mean 1.5). In 93.4 % of these 318 patients, success was reached by PVAI alone. Five percent of the recurrences after PVAI were based on left-sided atrial flutter (AFl) or atrial tachycardia (AT). Independent predictors for arrhythmia recurrence after the last ablation were persistent and long-standing persistent AF (figure), female sex, hypertension and AF-duration. Conclusion: Long-term freedom of atrial arrhythmia can be achieved by PVAI alone in a substantial number of patients suffering from AF. Left-sided AFl an AT were a rare finding during follow-up. This argues for a restrained primary approach.

14–24 Abstract 18–18

126 SAFETY OF THE 56-HOLE OPEN IRRIGATION ABLATION CATHETER IN PULMONARY VEIN ISOLATION FOR ATRIAL ABLATION

Wahaj Aman¹, Mohamed Bassiouny¹, Ayman Hussein¹, John Rickard², Khaldoun Tarakji¹, Bryan Baranowski¹, Thomas Callahan¹, Mandeep Bhargava¹, Thomas Dresing¹, Mohamed Kanj¹, Patrick Tchou¹, Bruce Lindsay¹, Walid Saliba¹, Oussama Wazni¹

¹ Cleveland Clinic, Cleveland, OH, USA; ² John Hopkins, Baltimore, MD, USA

Introduction: Data regarding the safety of use the 56-hole open irrigation radiofrequency (RF) ablation catheter (Thermocool SF, Biosense-Webster, Diamond Bar, CA) in pulmonary vein isolation (PVI) are controversial with recent reports of higher incidence of fatal atrial-esophageal fistulas and acute cardiac tamponade. Our study reports on the acute procedural outcomes of PVI using the 56-hole catheter in a high-volume center. Methods: Data from all consecutive PVI performed using the 56-hole, 3.5 mm, open-irrigation, radiofrequency ablation catheter between June 2012 and June 2014 were analyzed for complications. All four pulmonary veins were isolated guided by fluoroscopy, 3D navigation, and intracardiac echocardiography. RF delivery was power-controlled with up to 30 W along the posterior wall and 40 W elsewhere. Esophageal temperature was continuously monitored and RF was discontinued if temperatures above 39 °C or with rapid rise. Results: Four hundred sixty-six patients underwent PVI, 108 females (23 %), with a mean age of 62.6 ± 10.0 years, paroxysmal AF in 195 (42 %), persistent AF in 269 (58 %), and AFL in 2 (0.4 %). The median AF Duration since diagnosis was 48 months (IQR 24, 96); mean LVEF was 55.1 ± 9.8 %. Mean CHA2DS2-VASC was 2.1 ± 1.5, CAD 93 (20 %), CHF 101 (22 %), DM 54 (12 %), HTN 252 (54 %); TIA/Stroke 49 (11 %), age ≥65, 221 (47 %), age ≥75, 48 (10 %). Average procedure time was 242 ± 77.3 min and radiation exposure was 0.51 ± 0.36 Gy. Ninety-nine cases (21 %) were done under general anesthesia. Thirty-day complications included four pericardial effusions (0.9 %): acute tamponade in three (0.6 %),and mild-moderate pericardial effusion requiring no intervention in one (0.2 %), one ischemic stroke (0.2 %), and seven groin hematoma (1.5 %). On long-term follow-up, moderate to severe PV stenosis occurred in nine patients (1.9 %). There were no atrio-oesophageal fistulae and no deaths. Conclusion: PVI using the 56-hole open-irrigation ablation catheter was not associated with excess complication on short and long-term follow-up.

14–25 Abstract 15–35

127 CLINICAL 1-YEAR EXPERIENCE WITH A NOVEL MULTIPOLAR IRRIGATED ABLATION CATHETER IN AF ABLATION PROCEDURES

Reza Wakili¹, Johannes Siebermair¹, Eva Klocker¹, Stephanie FIchtner¹, Stefan Sattler¹, Moritz F. Sinner¹, Lucia Olesch¹, Samira Saraj¹, Christoph Schuhmann¹, Stefan Kääb¹, Heidi Estner¹

¹ Medizinische Klinik und Poliklinik I, Grosshadern Clinic, University of Munich, Munich, Germany

Introduction: Pulmonary vein isolation (PVI) is an established method to treat atrial fibrillation (AF). However, PVI is still a time-consuming procedure. Thus, new methods are necessary to improve procedural parameters. A novel multipolar irrigated radiofrequency (RF) ablation catheter is a new tool trying to improve PVI procedures by generating more effective lesions in a short time. In this study, we investigated the influence on procedural parameters using a multipolar irrigated ablation catheter (MIAC). Methods: We investigated 48 consecutive patients with AF undergoing PVI, two groups: (1) n = 24, standard ablation catheter (SAC, Thermocool Biosense Webster©), and (2) n = 24, MIAC (nMARQ™ Biosense Webster©). Procedural endpoint (PE): complete electrical isolation of all PVs. Study endpoints were left atrial (LA) procedure time (PT), fluoroscopy time (FT), radiation dose (RD), RF time, percentage of dormant PV conduction (adenosin), number of energy applications (EA) and clinical outcome. In all MIAC patients, an additional confirmation of PV disconnection was performed by a separate circular mapping catheter (CMC). All MIAC patients underwent periprocedural phrenic nerve stimulation, esophagus temperature monitoring, and endoscopy post PVI for safety assessment. Results: Patient characteristics did not differ significantly between both groups. PE was reached in all patients in the SAC group. However, in the MIAC group in >50 % (13/24) of all patients, PE of PV disconnection, suggested by the MIAC mapping, could not be confirmed with the CMC. Despite further MIAC ablation PE could still not be achieved in 5/24 patients. Mean FT, RD, LA PT or PV dormant conduction did not differ between both groups. However, number of EA (20 ± 1 vs. 29 ± 4, p < 0.05) and cumulative RF time (16 ± 1 vs. 24 ± 5 min, p < 0.001) to achieve PVI were significantly lower in MIAC group vs. SAC. Analysis of clinical outcome revealed no differences meanbetween both groups (freedom from AF MIAC 85 % vs. SAC: 76 %, mean follow-up of 263 ± 131 days). Regarding safety, one catheter charring event, one phrenic nerve injury (despite prophylactic stimulation), and one thermal esophageal lesions was observed in the MIAC group. Conclusions: In our small cohort, ablation with MIAC, under phrenic nerve and esophagus temperature monitoring, seems to still bear a potential for complications along with important device related limitations to successfully assess and achieve PV disconnection. Furthermore, ablation with MIAC failed to show significant benefits regarding relevant procedural parameters or clinical outcome compared to a SAC cohort.

14–26 Abstract 28–19

128 EARLY CLINICAL EXPERIENCE WITH THE RHYTHMIA 3D MAPPING SYSTEM: RAPID, AUTOMATIC, ACCURATE, HIGH-DENSITY MAPPING OF COMPLEX ARRHYTHMIAS FACILITATES SUCCESSFUL ABLATION

Markus Sikkel¹, Vishal Luther², James Harrison¹, Louisa Malcolm-Lawes¹, Sajad Hayat¹, Fu-Siong Ng², Ian Wright¹, Norman Qureshi², Kevin Leong², Nicholas Linton¹, Michael Koa-WIng¹, David Lefroy¹, Phang Boon Lim¹, Zachary Whinnett², Nicholas Peters², Prappa Kanagaratnam¹, D Wyn Davies¹

¹ Imperial NHS Healthcare Trust, London, UK; ² Imperial College, London, UK

INTRODUCTION: Current 3D electroanatomical mapping systems offer limited point density and attaining high-resolution activation maps is time consuming. The new Rhythmia mapping system circumvents these issues using a small 64-electrode roving basket array catheter and automation of mapping. This study presents our initial experience. METHODS: Seven patients (71 ± 4.7 years, five male) were mapped using Rhythmia. System performance was assessed by: time taken to map the arrhythmia, number of mapping points collected, requirement for manual correction and contribution to successful ablation. RESULTS: The LA was mapped in four patients (for recurrent PAF/AT post-AF ablation), the RA was mapped in two patients (for focal para-AV nodal AT/typical atrial flutter) and the LV was mapped in one patient (for post MI VT). Mean procedure time was 187 ± 70 min and fluoroscopy time was 33 ± 21 min; 12,152 ± 5959 points were collected per map over 18.6 ± 12 min (948 ± 516 beats, at a rate of 13.8 ± 9.5 points per second). Chamber volume was 117 ± 44 cm³ giving an approximate point density of 115 ± 74 points/cm² (assuming sphericity). The system guided successful re-isolation of PVs using the basket to map PV activation. It demonstrated a gap in a WACA around the RPVs allowing re-isolation with two adjacent RF applications (Figure). When differential pacing had shown CTI conduction block, it demonstrated persistent, slow concealed CTI conduction directing further successful ablation. CONCLUSION: Early experience of the Rhythmia mapping system is of a versatile and accurate 3D mapping system rapidly creating high-density maps that facilitate ablation of complex arrhythmias.

14–27 Abstract 28–18

129 DOES ATRIAL FIBRILLATION ORGANIZE SPATIALLY OR TEMPORALLY BEFORE TERMINATION? CONTINUOUS TRACKING OF SPATIO-TEMPORAL PERIODICITY DURING ABLATION

Junaid Zaman¹, Rishi Trikha¹, Tina Baykaner², David Krummen², Paul Wang¹, Wouter-Jan Rappel², Sanjiv Narayan¹

¹ Stanford University, Stanford, CA, USA, ² University of California, San Diego, San Diego, CA, USA

Introduction: During ablation, organized atrial fibrillation (AF) is sometimes difficult to separate from macro-reentrant tachycardia (AT) that may vary in rate or exit sites. Mechanistically, this distinction may define fibrillatory conduction, and clinically, it directly impacts entrainment or ablation. We hypothesized that organization of AF to AT initiates spatially, with later elimination of rate fluctuations, and tested if it can be tracked from ECG or intracardiac leads during AF ablation. Methods: We studied 17 AF patients at ablation (age 58 years, persistent 54 %) with transitions to AT. From 64 pole baskets (Boston Scientific) and the ECG, we measured 3-dimensional spatial and temporal periodicity in AF at 15, 10, 5, 3 and 1 min prior to AT (defined clinically) using sliding-correlation spatial loops and width of the Fast-Fourier spectral dominant frequency using custom software (Labview). Results: Spatial organization of AF occurred minutes before onset of AT (predominantly left atrial), on ECG (p < 0.05, fig A). Temporal organization occurred later. Fig B shows spatial variability 10 min before AT, but spatial consistency 1 min prior to AT (fig C). This “anticipatory” organization was most marked in the XY plane (p < 0.05). Intra-cardiac leads showed less consistency throughout ablation and were more sensitive to actual AT location. Conclusions: During ablation, AF shows anticipatory organization even before termination to AT, first spatially then temporally. Studies should determine if ablating in regions causing anticipatory organization better eliminates AF, and whether this may form the basis for a quantitative classification separating AT from AF.

14–28 Abstract 01–20

130 MIGHT CARDIOVERSION BE THE END-POINT FOR RADIOFREQUENCY ABLATION OF LONG-LASTING PERSISTENT ATRIAL FIBRILLATION PATIENTS: EXTRAPOLATION OF MATHEMATICAL MODELING DATA TO CLINICAL RESULTS OF ABLATION

Andrey Ardashev¹, Mikhail Mazurov², Yury Belenkov³, Ilia Kolodyazhny², Vasily Finko¹, Evgeny Zhelyakov¹

¹ Federal Scientific and Clinical Centre of FMBA, Moscow, Russia; ² Moscow University of Economic, Statistic and Informatic, Moscow, Russia; ³ Lomonosov State University, Moscow, Russia

Aim: The study aims (1) to estimate theoretical probability of existing of 6-wave re-entry as a model of long-lasting persistent AF and (2) to extrapolate mathematical modeling data to clinical results of linear ablation in patients with long-lasting persistent AF. Material and methods: clinical phase. Study was conducted on consecutive 20 patients (6 women, 58.2 ± 10.6 years of age) with long-lasting persistent AF who underwent index RFA. Ablation approach consisted of three steps. The first step was antral isolation of PVs, the second step included mitral isthmus ablation and the third step was linear roof ablation. We evaluated AF CL into the CS after each step. Mathematical phase. As the first step numeric reconstruction of the autowave process in excitable tissues of the LA and the simulation of 6-wave re-entry AF was performed using Fitzhugh-Nagumo equation. A special scanning method was used for calculating characteristics of autowave processes in a 2D mathematical model in LA. Then, ablation formatting (corresponding to all ablation lines) was performed. Results: clinical phase. Organization of AF CL (from 112 ± 24 to 204 ± 35 ms) was verified in 12 of 20 patients during ablation. SR was effectively restored after external cardioversion at the end of procedure in all patients. Mathematical phase. Ablation formatting (corresponding to linear ablation) transformed 6-wave re-entry to 4-wave re-entry. Following mathematical simulation of cardioversion effectively terminated 4-wave AF, whereas did not terminate 6-wave re-entry AF. Conclusion: (1) Mathematical modeling of 6-wave re-entry and linear ablation formatting may simulate long-lasting persistent AF and subsequent AF organization due to antral and linear ablation. (2) Transformation of 6-wave re-entry to 4-wave reentry with following AF termination after cardioversion may be effective ablation end-point recording tj mathematical approach. Our clinical results are consistent with ablation formatting data.

14–29 Abstract 05–13

131 THE IMPACT OF CATHETER CONTACT FORCE ON HUMAN LEFT ATRIAL ELECTROGRAM CHARACTERISTICS IN SINUS RHYTHM AND ATRIAL FIBRILLATION

Waqas Ullah¹, Ross Hunter¹, Baker Victoria¹, Liang-han Ling², Mehul Dhinoja¹, Simon Sporton¹, Mark Earley¹, Richard Schilling¹

¹ St Bartholomew’s Hospital, London, UK; ² Alfred Hospital and Baker IDI Heart and Diabetes Institute, Melbourne, Australia

BACKGROUND: During left atrial (LA) mapping, optimal contact parameters minimizing variation secondary to catheter contact are not established. METHODS: In patients undergoing first-time ablation for AF, stable mapping points comprising 8 s of contact force (CF) and bipolar electrogram data were analysed. Points were taken at locations in groups, with CF or catheter orientation actively changed between acquisitions. This allowed for a paired analysis to establish the effect of catheter contact on the electrogram. For points taken in persistent AF patients, automated complex fractionated electrogram (CFAE), dominant frequency (DF) and organization index (OI) analysis were performed. RESULTS: Thirty patients were studied: 15 with persistent AF and 15 paroxysmal AF. In total, 1965 mapping points were collected: 1409 in AF and 556 sinus rhythm (SR). Complexes were less positive at higher CF (Pearson’s correlation −0.2, p < 0.005, both rhythms). Increasing CF at a location significantly increased complex size, but only where initial CF was <10 g, and the change was ≥4.5 g in SR or ≥8 g in AF (Table). Atrial ectopics in SR were observed more frequently when CF was ≥10 g (p < 0.0005). Increasing CF at a location was associated with increasing CFAE interval confidence level score, but only if initial CF was <10 g and CF increased ≥8 g (p = 0.003). The dominant frequency (DF) and organization index (OI) were unaffected by CF (p > 0.1 for both). Changing catheter orientation from perpendicular to parallel was associated with smaller, more positive complexes (p = 0.001 for both), but no change in CFAE scores, DF or OI (p > 0.08 for each).

Rhythm	Initial CF in a pair	Increase in CF between paired measurements
		<4.5 g SR and <8 g AF		≥4.5 g SR and ≥8 g AF
		Median change in complex size (%)	p	Median change in complex size (%)	p
SR	1–10 g	6 [−8–34]	0.06	13 [−16–60]	<0.005
	≥10 g	3 [−8–22]	0.28	−0.3 [−29–26]	0.43
AF	1–10 g	0 [−12–16]	0.28	6 [−11–41]	<0.005
	≥10 g	2 [−13–18]	0.09	0 [−16–24]	0.12

CONCLUSIONS: During LA mapping, including CFAE but not spectral parameter mapping, CF and catheter orientation influence results. Low CF (<10 g) is associated with lower measured electrogram amplitude and hence reduced apparent fractionation. Mapping CFs should therefore be ≥10 g to avoid CF-dependent electrogram variation. Spectral measurements are unaffected by catheter contact, suggesting this does not significantly impact on the underlying physiology.

14–30 Abstract 15–56

132 RADIOFREQUENCY ATRIAL FIBRILLATION ABLATION USING 3D MAPPING SYSTEM NAVIGATION: FIRST SINGLE-CENTRE EXPERIENCE IN NORTH AFRICA.

Sonia Marrakchi¹, Azima Ben Tanfous¹, Bechir Zouari², Abdelatif Lefi¹, Hend Keskes¹, Afef Ben Halima¹, Faouzi Added¹, Ikram Kammoun¹, Salem Kachboura¹

¹ Abderrahmane Mami Hospital, Tunis, Tunisie; ² Tunis Medical University, Tunis, Tunisia

Background: We report the first single-centre experience in North Africa with the navigation system in an unselected subset of patients with atrial fibrillation (AF). Methods: Data were recorded prospectively of all consecutive patients who underwent atrial fibrillation ablation with radiofrequency and 3D mapping navigation system at the Aberrahman Mami Hospital, in Tunisia, in North Africa, from January 2010 to December 2013. Outcomes were defined every 3 months. Results: A total of 35 patients were included: 80 % had paroxysmal AF and 17 % had persistent AF and 3 % had longstanding persistent AF. The mean procedure, fluoroscopy and ablation times were 21 ± 10 min (with extreme 8–58 min) and 180 min, respectively. The procedural endpoint of the study was successfully achieved in 98 % patients. The follow up was 17.72 months. At a median of 17.72 months follow-up, 34 % had atrial fibrillation recurrence. Six patients had two procedures. The mean of procedure was 1.2 per patient. Seventy-four percent were AF-free off anti-arrhythmic drugs AADs, and 89 % were AF-free on AADs. Conclusion: The 3D mapping navigation system offers a safe and effective approach for the treatment of AF in North Africa. There was a learning curve with regard to fluoroscopy and procedure time, after which point reduction in radiation exposure and operator strain, as well as improvement in procedure throughputs were even more pronounced.

Screening athletes

14–31 Abstract 07–16

133 ELECTROCARDIOGRAPHIC AND ECHOCARDIOGRAPHIC EVALUATION OF A LARGE COHORT OF YOUNG SOCCER PLAYER’S DURING PRE-PARTICIPATION SCREENING.

Annamaria Martino¹, Fabio Sperandii¹, Emanuele Guerra¹, Elena Cavarretta², Federico Quaranta³, Attilio Parisi³, Antonia Nigro², Luigi Sciarra¹, Ermenegildo de Ruvo¹, Antonio Spataro⁴, Fabio Pigozzi³, Leonardo Calo’¹

¹ Cardiology Department, Policlinic Casilino, Rome, Italy; ² FMSI Sport Medicine Institute, Villa Stuart Sport Clinic-FIFA Centre of Excellence and Department of Medical-Surgical Sciences and Biotechnologies, Sapienza University, Rome, Italy; ³ Department of Health Sciences, University of Rome “Foro Italico”, Rome, Italy; ⁴ Institute of Sports Medicine and Science (CONI), Rome, Italy

Background. The early diagnosis of cardiac abnormalities in young athletes may be helpful not only to identify subjects potentially at risk of sudden cardiac death but also to prevent evolution towards cardiac dysfunction. The aim of our study was to investigate the prevalence of cardiac abnormalities in a population of young male soccer players undergoing pre-participation screening (PPS) through ECG and transthoracic echocardiography (TTE). Methods. All consecutive male football players undergoing PPS in the FMSI Sport Medicine Institute in Rome, between January 2008 and March 2009, were enrolled in the study and underwent standardized medical history, physical examination, 12-lead ECG and TTE. Results. The study population consisted of 2261 consecutive young athletes aged 12.4 ± 2.6 years. Positive family history for cardiovascular disease was present in 1.9 % of athletes. Cardiac symptoms and abnormal physical examination were present in 1.2 and 0.8 % of the study populations, respectively. Uncommon and training-unrelated ECG abnormalities and anomalous TTE examinations were observed in 182 (8 %) and 102 (4.5 %) athletes, respectively. Abnormal ECG was associated with anomalous TTE in 11/182 (6 %) cases, including two hypertrophic cardiomyopathy and two mild left ventricular hypertrophy. Among 2079 athletes with normal ECG, 92 cases of cardiac abnormalities at TTE were observed. TTE abnormalities were associated with pathological ECG in 9/102 (8.8 %) cases. Conclusions. In a wide population of young male athletes undergoing PPS, the combination of ECG and TTE allowed the identification of several otherwise underdiagnosed electrical and structural cardiac abnormalities, requiring sport disqualification in some cases or periodic follow-ups over time.

Monday, April 20, 2015

Poster session C part 1

Posters exposed from 8:30 AM to 12:00 PM

Presenters and chairpersons present from 09:00 AM to 10:30 AM

Cardiac resynchronization therapy

15–1 Abstract 24–26

134 CARDIAC RESYNCHRONIZATION THERAPY: LEFT VENTRICULAR LEAD PLACEMENT GUIDED BY CORONARY VENOUS ELECTROANATOMIC MAPPING

Massimiliano Maines¹, Carlo Angheben¹, Massimiliano Marini², Alessio Coser², Domenico Catanzariti¹, Maurizio Del Greco¹

¹ Santa Maria del Carmine Hospital, Rovereto, Italy; ² Santa Chiara Hospital, Trento, Italy

Introduction. The implant of cardiac resynchronization therapy (CRT) devices driven by non-fluoroscopic navigation systems demonstrates how an electroanatomical mapping of the coronary sinus for the optimization of the left electrode placement, is feasible. Purpose. The aim of this study was to evaluate the latest activated region in coronary sinus (CS) in patients who underwent CRT devices implant. Methods and results: 46 consecutive CRT patients (38 males, age 72.9 ± 7.3 years) underwent intra-procedural coronary venous EAM using EnSite NavX. A guidewire was used to map the coronary veins during intrinsic activation and right ventricular (RV) pacing. The latest activated regions are reported in Table 1.

Delay in LAO	Latest activation during spontaneous rhythm—number of patients	Latest activation during RV pacing—number of patients
Anterior	2	10
Antero-lateral	8	8
Lateral	27	18
Postero-lateral	8	10
Posterior	1	0
Delay in RAO
Basal	25	16
Medium	16	15
Apical	5	15

Conclusion. Coronary venous EAM can be used intra procedurally to guide LV lead placement to the latest activated region. This approach especially contributes to optimization of LV lead electrical delay in patients with multiple target veins. Conventional anatomical LV lead placement strategy does not target the vein with maximal electrical delay in many of these patients.

15–2 Abstract 24–11

135 ACUTE HEMODYNAMIC MEASUREMENTS AND CONTACT ACTIVATION MAPPING DURING MULTIPOINT LEFT VENTRICULAR PACING

Antonello Vado¹, Endrj Menardi¹, Ballari Gian Paolo¹, Guido Rossetti¹

¹ Ospedale S. Croce e Carle, Cuneo, Italy

Background. MultiPoint left ventricular (LV) pacing (MultiPoint™ Pacing [MPP], St. Jude Medical, Sylmar, CA) in a single coronary sinus branch has been introduced as a novel means of cardiac resynchronization therapy (CRT). It may improve CRT response by capturing a larger LV tissue area than conventional biventricular (BIV) pacing. We evaluated this new feature by means of contact mapping and hemodynamic measures in order to understand the underlying mechanisms and effects. Methods. Ten non-ischemic patients (69 ± 9 years, 6 males, NYHA class II or III, QRS duration 173 ± 20 ms, LVEF 27 ± 5 %) received a CRT-Defibrillator (Quadra Assura MP™, St. Jude Medical, Sylmar, CA) with the ability to deliver MPP. After the implantation procedure, an acute pacing protocol was implemented, including two BIV configurations, by using a proximal and a distal LV pacing vector and up to nine MPP interventions. In all the pacing configurations, in addition to QRS duration (QRSd), LV electrical activation patterns and hemodynamics (dP/dtmax) were evaluated by means of EnSite™ NavX™ (St. Jude Medical, St. Paul, MN) and PressureWire CertusTM (St. Jude Medical, St. Paul, MN), respectively. For each of the parameters analyzed, the best values resulting from the MPP and BIV pacing configurations were selected and compared. Results. We observed an increase in dP/dtmax (30 ± 13 vs. 25 ± 11 %; p = 0.041), a reduction in QRSd (22 ± 11 vs. 11 % ± 11; p = 0.01) and a decrease in total activation time (TAT) (25 ± 15 vs. 10 % ± 20; p = 0.01). Furthermore, during the first 25 ms after pacing, the electrically activated LV portion was greater during the best MPP configuration (35 ± 22 vs. 16 % ± 8; p = 0.005). The MPP wavefront was also faster during the first 50 ms, resulting in the activation of only 60 ± 23 % of the endocardial LV during BIV, versus 78 ± 27 % during MPP pacing (p = 0.03). Conclusions; In this acute study, MultiPoint left ventricular pacing in CRT improved both endocardial and surface electrical parameters and hemodynamics in comparison with conventional biventricular pacing

15–3 Abstract 24–12

136 COMPARISON BETWEEN NEUROHORMONAL PROFILE AFTER IMPLANT OF BIVENTRICULAR ICD AND PROFILE AFTER BIVENTRICULAR ICD WITH MULTIPOLAR PACING IN PATIENTS WITH HEART FAILURE

Domenico Spaziani¹, Laura Striuli¹, Roberto Turato¹, Pasquale Gangitano¹, Maurizio D’Urbano¹, Guido Grassi²

¹ Ospedale Fornaroli, Magenta, Italy, ² Università Milano-Bicocca, Milano, Italy

Background: The benefits of resynchronization therapy (RT) on the functional heart profile are well defined and largely dependent on a more organized movement of left ventricle. The RT for heart failure (HF) reduces mortality, hospitalization rate and improves ejection fraction. Also the neurohormonal profile (NHp) after implant of biventricular ICD (biv-ICD) is improved as documented by the behavior of sympathetic markers such as plasma norepinephrine and epinephrine (NE/E). The aim of our study was to compare the NHp after implant of biv-ICD to single polar pacing in coronary sinus or with new multipolar pacing (MPP) by new catheter St. Jude Medical. Method: Ten patients (pts) got single polar biv-ICD and eight pts got MPP. We evaluated their activation profile by brain natriuretic peptide (BNP) and NE/E before the implant and after 1 month. All pts were at optimal medical therapy, sinus rhythm and had a previous hospitalization for HF. Results: In both groups, there were a significant reduction after 1 month of all markers (BNP-NE/E): p\0.05. No significant differences were seen between single polar biv-ICD group and MPP group. Conclusions: pts with dilated cardiomyopathy implanted with biv-ICD and with a good anatomical target pacing in coronary sinus can improve their NHp after RT. The benefits are similarly manifest in both groups, this being the case also for the changes in neurohormonal variables.

	Pre-implant	Post-implant
Group 1 (10 pts)	BNP 2865 pg/ml	BNP 420 pg/ml
	NE 750 pg/ml	NE 280 pg/ml
	E 92 pg/ml	E 47 pg/ml
Group 2 (8 pts)	BNP 2375 pg/ml	BNP 370 pg/ml
	NE 813 pg/ml	NE 299 pg/ml
	E 89 pg/ml	E 40 pg/ml

15–4 Abstract 24–16

137 DISTRIBUTION OF ESOPHAGEAL INTERVENTRICULAR CONDUCTION DELAYS IN CRT PATIENTS AND HEALTHY SUBJECTS

Johannes Härtig¹, Anna Nagel², Kirsten Rotter², Tobias Haber², Laura Perez Escobar², Juraj Melichercik¹, Bruno Ismer²

¹ MediClin Heart Center Lahr/Baden, Lahr, Germany, ² Peter Osypka Institute for Pacing and Ablation, Offenburg, Germany

Accurate selection of eligible patients as well as optimal specification of their individual left ventricular electrode position can increase responder-rate in cardiac resynchronization therapy (CRT). This could be fulfilled preoperatively by selecting patients characterized by a distinct interventricular conduction delay and intraoperatively by placing the LV electrode within a desynchronized left ventricular region. Esophageal left heart electrogram was proposed (applied) in symptomatic heart failure patients in sinus rhythm or atrial fibrillation, preoperatively, to measure interventricular conduction delay (IVCD), to justify CRT and to intraoperatively guide the left ventricular electrode placement. Nevertheless, there is a lack concerning the distribution of esophageal IVCDs in healthy subjects. Aims: The study aims to compare the esophageal IVCDs between guideline CRT patients and healthy subjects. Methods: Esophageal IVCD was measured between onsets of QRS in surface ECG and left ventricular deflection in the esophageal left heart electrogram by perorally applied 4 F bipolar electrode (Osypka TOslim) in position of maximum left ventricular deflection using the Biotronic ICS3000 esophageal electrogram feature in 32 consecutive symptomatic heart failure patients (24 male, 8 female, 66.5 ± 7.8 years) 1 week after implantation of CRT systems according to the guidelines. Results were compared with IVCDs of 31 healthy medical engineering students (24 male, 7 female, 21.4 ± 3.2 years) volunteered during their “Cardiological devices and methods” internship. Results: In the CRT patients with sinus rhythm, left bundle branch block and QRS width of 168.2 ± 21.4 ms, we found IVCDs of 66.7 ± 18.9 ms with minimum of 37 and maximum of 108 ms. In the healthy students with QRS of 87.8 ± 9.9 ms, IVCDs of 17.4 ± 3.9 ms with minimum of 11 and maximum of 23 ms were measured. Between both groups, esophageal IVCDs differed significantly by p = 0.000000. Conclusions: Esophageal IVCDs differ highly significantly between CRT patients and healthy subjects. Thus, it could be used as an additional parameter to characterize ventricular desynchronization. Guideline CRT was found to be linked with IVCDs of about 40 ms and more.

15–5 Abstract 24–18

138 RIGHT VENTRICULAR SEPTAL PACING IN PATIENTS WITH RIGHT BUNDLE BRANCH BLOCK, ELECTRO- AND ECHO-CARDIOGRAPHIC OUTCOMES

Belal Al Khiami¹, Basil Abu-El-Haija¹, Omer Iqbal¹, Paul Lindower¹, Michael Giudici¹

¹ University of Iowa Hospitals and Clinics, Iowa City, IA, United States

BACKGROUND: Cardiac resynchronization therapy (CRT) has shown improvement in left ventricular (LV) size and function and survival in heart failure patients with reduced LV ejection fraction (HFrEF) and LBBB. Patients with RBBB, however, do not have a similar positive response to standard CRT with an LV lead in a lateral cardiac vein and apical right ventricular (RV) lead; in fact, they may do worse. We hypothesized that pacing the right ventricular mid-septum (RVS) near the right bundle minimizes the conduction abnormalities in RBBB patients and improves biventricular size and function. METHODS: We studied 78 patients (72 % male, 28 % female; 74 ± 11 years old) with RBBB and underwent pacemaker or ICD implantation for standard indications. Baseline PR interval 206 ± 40 ms, pre-implant QRS duration 147 ± 19 ms. Active-fixation leads were placed in the right atrium and RVS. The AV delay was adjusted at the bedside to yield the narrowest QRS. We reviewed retrospectively baseline pre-implant and follow-up post-implant echocardiograms on a sample of 8 patients with mean follow-up of 384 ± 200 days of RBBB pacing for the following parameters: LV ejection fraction (LVEF) by method of discs, LV end-systolic and end-diastolic volumes (LVESV and LVEDV) by biplane method, RV end-diastolic diameter (RVIDd), mitral and tricuspid regurgitation (MR and TR) by color Doppler, and septal wall motion abnormalities (WMA) by visual assessment. Results: At the optimal AV delay, QRS duration was 112 ± 20 ms with a mean QRS narrowing of 34 ± 20 ms (p < 0.001). In echocardiogram samples, RVIDd significantly decreased on follow-up (from 38 ± 2.8 to 35 ± 3.7 mm, P = 0.035), and septal WMA resolved in 4/5 patients. However, improvement in LV volume and function was not statistically significant (P > 0.05); (LVEF from 47 ± 15.8 to 48.8 ± 10.1 %; LVESV from 81 ± 60.9 to 65.3 ± 36.5 ml; LVEDV from 140 ± 79.6 to 120.4 ± 46.7 ml). Overall, there was only mild/trace MR or/and TR at baseline with no significant difference on follow up. Conclusion: RVS pacing in RBBB patients resulted in significant improvement of electrical synchronization and RV size but without significant improvement in LV size and function, though our results showed a positive trend. The small sample size and marginal baseline LVEF are the main limitations. A Clinical trial to test this novel CRT therapy in patients with RBBB and HFrEF is warranted to confirm the above results in this group.

15–6 Abstract 24–22

139 PATIENTS WITH LEFT BUNDLE BRANCH BLOCK AND LEFT AXIS DEVIATION SHOW A SPECIFIC LEFT VENTRICULAR ASYNCHRONY PATTERN: POSSIBLE IMPLICATIONS FOR LEFT VENTRICULAR LEAD PLACEMENT DURING CRT IMPLANTATION

Luigi Sciarra¹, Paolo Golia², Monia Minati¹, Ermenegildo De Ruvo¹, Antonio Scarà¹, Alessio Borrelli¹, Lucia De Luca¹, Chiara Lanzillo¹, Alessandro Fagagnini¹, Marco Rebecchi¹, Ludovica Scialla¹, Elisa Salustri³, Domenico Grieco¹, Leonardo Calò¹

¹ Cardiologia - Università La Sapienza, Rome, Italy; ² Cardiologia - Ospedale di Forlì, Forlì, Italy; ³ Cardiologia - Università de L’Aquila, L’Aquila, Italy

Background: It has been observed that candidates to cardiac resynchronization therapy (CRT) with an ECG pattern of left bundle branch block (LBBB) and left axis deviation (LAD) may have a worse response to biventricular pacing. A possible reason of this observation could be that the left ventricular lead is normally placed in a postero-lateral branch of the coronary sinus, but the postero-lateral left ventricular wall could not be the most delayed one in such a subgroup of subjects. Aim of our study: to test if patients with LBBB and left axis deviation show a specific asynchrony echocardiographic pattern. Methods: Our study population included 17 patients (14 males; mean age 71.8 ± 8.4 years) with severe depression of ventricular function (mean ejection fraction 0.26 ± 0.09), advanced heart failure (mean NYHA class 2.8 ± 0.5), complete LBBB (mean QRS duration 175 ± 28 ms) with LAD at the surface ECG. All patients were candidate to CRT through biventricular pacing. Every patient underwent an echocardiogram with tissue-doppler analysis, in order to evaluate the asynchrony pattern of the left ventricular contraction. The time from the QRS onset to maximum wall velocity (Q-peak) at tissue Doppler was evaluated in different areas of the left ventricle: septum, inferior, postero-lateral, and antero-lateral wall. Results: The mean Q-peak time at tissue Doppler analysis resulted to be significantly prolonged in the antero-lateral wall, when compared to the other regions (280.0 ± 68.2 vs 210.8 ± 54.4 ms; p = 0.001). In all but two patients, the most delayed wall resulted to be the antero-lateral one. The patients without significant antero-lateral delay had a previous anterior myocardial infarction. Conclusions: Patients with advanced heart failure, severe depression of left ventricular systolic function, and complete LBBB with left axis deviation at the surface ECG show a specific pattern of ventricular asynchrony with delayed activation of the antero-lateral wall. Our results may have clinical impact in target vessel identification during CRT implantation in pts with LBBB and LAD.

15–7 Abstract 24–23

140 PROGNOSTIC VALUE OF EPICARDIAL-ENDOCARDIAL GRADIENT MEASURED BY ECHOCARDIOGRAPHY TO PREDICT CARDIAC RESYNCHRONIZATION THERAPY (CRT) RESPONSE

Frederic Sebag¹, Nicolas Lellouche¹, Nicolas Mignot¹, Nathalie Elbaz¹

¹ Departement de Cardiologie CHU Mondor, CRETEIL, France

Introduction: Cardiac resynchronization therapy (CRT) is an effective treatment for patients with systolic heart failure and cardiac dyssynchrony. However, up to one third of patients do not respond to CRT. As right ventricular (RV) lead is positioned endocardialy and left ventricular (LV) lead epicardialy, we hypothesized that baseline epi-endo gradient could predict CRT response. Methods: We studied 46 patients referred to our centre for CRT. These patients had LVEF <35 % and QRS duration >120 ms under maximal medical therapy. Transthoracic echocardiography (TTE) was performed for all patients before and 1 year after CRT implantation. Offline analysis with a specific software (Echo PAC from GE) allowing speckle tracking imaging (STI) analysis of LV endocardial and epicardial wall was performed. Specifically, epi-endo gradient delay (GD) and gradient contraction (GC) measurements were performed on the septal and lateral LV wall before and at 1 year after CRT implantation. CRT response was defined as a reduction >15 % of LV end systolic volume 1 year after CRT. Results: In our population, mean age was 62 ± 11 years old and mean LVEF was 26 ± 7 %. Twenty-two patients (48 %) were classified as responders. Baseline characteristics of patients with or without CRT response were similar. However, baseline QRS duration was higher in patients with CRT response (160 ± 35 vs. 140 ± 27 ms, p = 0.03). Before implantation, septal (10 ± 31 vs. 20 ± 133 ms, p = 0.67) and lateral GD (1 ± 25 vs. 4 ± 26 ms, p = 0.76) were low and similar in both groups. However, lateral GC was higher in CRT responders (−4.05 ± 2.29 vs. −2.38 ± 2.82 %, p = 0.009). After multivariate analysis, lateral GC was the best predictor of CRT response (p = 0.013). One year after implantation, septal GD and GC were comparable in CRT responders or not. However lateral GC significantly decreased in CRT responders (−4.05 ± 2.29 % at baseline vs. −1.86 ± 2.2 %, p < 0.01) whereas no changes were observed for non-responders. Finally, lateral GD was significantly increased at 1 year in CRT non responders 4 ± 26 ms at baseline vs. 18 ± 43 ms, p < 0.01). Conclusion: At baseline, no significant LV epicardial-endocardial delay gradient was observed in patients with CRT response or not. However, lateral epi-endo gradient contraction is highly independently associated with CRT response. Finally, this gradient was homogenizing 1 year after CRT for responders.

15–8 Abstract 24–24

141 LARGE CAPACITY LIMNO2 BATTERIES EXTENDED CRTD LONGEVITY IN CLINICAL USE COMPARED TO SMALLER CAPACITY LISVO BATTERIES OVER 6 YEARS

Ernest Lau¹, Carol Wilson¹, Kyle Ashfield¹, Wilson McNair¹, David McEneaney¹, Michael Roberts¹

¹ Royal Victoria Hospital, Belfast, UK

Introduction: CRTD batteries need to supply both regular low-voltage pacing impulses and occasional high-voltage defibrillation discharges. The longevities of CRTDs powered by large capacity LiMnO2 batteries (introduced in 2008) and contemporary smaller capacity LiSVO batteries after 6 years of clinical use were compared. Methods: CRTDs implanted in our hospital in 2008–9 were tracked for survival up to ERI. Non-ERI events removing devices from service were censored. Device models using the same batteries were grouped for analysis. Results: The 2 Ah LiMnO2 CRTDs (group 1) showed 100 % survival after 6 years. The 1.87 Ah (group 2) and 1.4 Ah (group 3) LiSVO CRTDs began to reach ERI after 2.8 and 2.5 years, respectively, and none were in service after 6 years in either group. Pairwise comparisons show significant differences between group 1 and group 2 (p = 0.0018), between groups 1 and 3 (p < 0.0001), and between groups 2 and 3 (p = 0.0386). Conclusions: Large capacity LiMnO2 CRTDs outlasted traditional smaller capacity LiSVO CRTDs in clinical use. Both battery chemistry and capacity impact device longevity.

Manufacturer	CRTD models	Chemistry	Capacity (Ah)		Ratio
			Total	Usable
Boston Scientific (group 1)	Cognis	LiMnO2	2	1.8	0.9
St Jude Medical (group 2)	Promote/Atlas HF	LiSVO	1.87	1.31	0.7
Medtronic (group 3)	Consulta/Concerto/Maximo	LiSVO	1.4	1.0	0.7

15–9 Abstract 24–27

142 ATRIAL REVERSE REMODELING AFTER CARDIAC RESYNCHRONIZATION THERAPY FOR HEART FAILURE

Alaa Allah Al Anany¹, Said Khaled¹, Mazen Ibrahim¹, Mohamed Abdel Hameed¹, Ayman Abdel Motalib¹, John Zarif¹

¹ Ain Shams University hospital, Cairo, Egypt

Background: Cardiac resynchronization therapy (CRT) improves LV functions and NYHA class in the majority of heart failure patients who met the criteria of CRT implantation. Aim: The aim of this study is to investigate whether CRT improves atrial function and induces atrial reverse remodeling. Methods: A total of 24 patients with heart failure (mean age, 55.3 ± 9.64 years) who underwent CRT were evaluated with echocardiography before and after 3 months of optimized CRT. Atrial function and LV function were assessed with M-mode, two-dimensional echocardiography, Doppler, tissue Doppler velocity, and 2D strain (E) imaging. LV reverse remodeling was defined as a reduction in LV end-systolic volume of >10 %. Results: In responders (n = 16), significant improvements in left atrial (LA) functional and structural remodeling were observed. LA area and volumes decreased, the LA emptying fraction increased, LA global positive longitudinal strain (E) increased from 12.45 ± 6.12 to 16.59 ± 5.89 % (P < 0.001), and LA global negative longitudinal (E) −1.62 ± 1.2 to −3.3 ± 1.9 (P < 0.003). LA reverse remodeling was more frequent in patients with LV reverse remodeling (P < 0.005). We also noticed the LA area and volumes were significantly less in the responders group prior to CRT implantation. Conclusions: CRT induce LA structural and electrical reverse remodeling that could be assessed more accurately by LA 2D (E) strain as well as LA volumes and functions. Keywords: Cardiac resynchronization therapy, left atrium, remodeling

Model	AUC (CI)	p value	Correct prediction (%)	Nagelkerke R square
Clinical + wide QRS	0.794 (0.692;0.897)	<0.001	74	0.336
Clinical + wide QRS + ECHO	0.802 (0.699;0.806)	<0.001	79.3	0.35
Clinical + wide QRS + ECHO+ Lab	0.842 (0.728;0.955)	<0.001	81	0.423
Clinical + wide QRS + ECHO + Lab + HM	0.879 (.786;.972)	<0.001	84.5	0.478

Table 1. Comparison of risk assessment models. AUC area under the curve, CI, confidence interval, EF echocardiography, HM Holter monitoring, Lab laboratory data

15–10 Abstract 31–11

143 EFFECT OF LEFT VENTRICULAR REMODELING ON ENDOCARDIAL SENSED R WAVE AMPLITUDES

Omer Iqbal¹, Lee Joseph¹, Siva Krothapalli¹, Miriam Zimmerman¹, Michael Giudici¹, Kanu Chatterjee¹

¹ University of Iowa hospitals and clinics, Iowa City, IA, USA

Background: Low R-wave sensed amplitude (RWSA) has been noticed in dilated cardiomyopathy and other cardiac conditions like arrhythmogenic hypertrophy cardiomyopathy, arrhythmogenic right ventricular cardiomyopathy (ARVC), and sarcoidosis and has been associated with high incidence of inappropriate ICD shocks in these patients. Also, at the time of ICD implantation, low RWSA < 9 mV has been associated with an increased risk of all-cause mortality when compared with RWSA > 15 mV in primary prevention population. It has not been studied if left ventricular (LV) remodeling can result in changes in endocardial RWSA. We conducted this study to determine the effect of LV remodeling on endocardial RWSA. Methods: A retrospective single-center review of endocardial RWSAs from 212 ICD and pacemaker interrogations in total 132 patients with bipolar leads was done. Interrogations of pacemaker-dependent patients and those receiving advanced heart failure therapies (left ventricular assisted device; cardiac transplant) were excluded. LV stroke volume (SV) and ejection fraction (EF) were measured on TTE by Simpson’s equation. Endocardial RWSA were correlated with LV dynamic variables (SV and EF). RESULTS: RWSAs were similar when compared between device types (biventricular versus right ventricular device; p = 0.102), lead locations (apex, right ventricular outflow tract, septum; p = 0.186), EF [%] (<50 and >50, p = 0.618). In patients without coronary artery disease (CAD), there was a significant increase in RWSA with decrease in SV (p = 0.008) and a non-significant trend towards increase in RWSA with decrease in EF (p = 0.06) (Figure 1). In the presence of CAD, there was no significant correlation between RWSA versus SV (p = 0.32) or RWSA versus EF (p = 0.30). Conclusion: In the absence of CAD, RWSA changes are inversely related to the changes in stroke volume; however, no such association was noted in the presence of CAD.

Arrhythmia mechanisms

15–11 Abstract 02–15

144 TISSUE STRUCTURE FUNCTION RELATIONSHIPS - SIZE AND DIRECTION DO MATTER.

Junaid Zaman¹, Sayed Al-Aidarous¹, Samha Alayoubi¹, Pravina Patel¹, Cesare Terracciano¹, Nicholas Peters¹

¹ Imperial College London, London, UK

Intro: We tested whether structure (connexin43, Cx43/fibrosis) function (electrograms Eg, conduction velocity, CV) relations vary with size of electrode and direction of pacing. Methods: Macro: Function—paced (6–33 Hz) Langendorff perfused rat hearts (3–12 m, n = 80). Microelectrode array (MiEA) mean and max CV calculated by isochronal mapping. AF (>30s) dominant frequency (DF), organizational index (OI), Shannon entropy (ShEn) andmagnitude squared coherence (MSC) calculated with small (30 mm), medium (150 mm) and large (1.5 mm) electrodes. Structure—whole atrial Cx43 phosphofractions (P0, P1, P2) and fibrosis. Micro: Function—superfused isolated atria (3, 12 and 20 m n = 40) on glass MiEAs, orthogonal pacing (1–25 Hz), unipolar Eg time and frequency domain characterization, optical mapping using di-4-ANEPPS. Structure—overlay grid of electrodes and fibrosis. Results: (1) Mean CV is inversely correlated to fibrosis. (2) Max/mean CV is correlated to Cx43 P0/P12 ratios. (3) In AF MiEA recordings, ShEn and MSC correlate with fibrosis at the smallest scale whereas DF and OI correlate with Cx43 at the largest scale only. (4) Unipolar Eg morphology correlates with duration, amplitude, line length, fractionation score, DF, DF dv/vt and ShEn only in one direction of pacing. (5) APD90 is inversely correlated to Eg duration and fractionation score. Conclusions: (1) CV is linearly related to interstitial fibrosis and Cx43 phosphorylation ratio. (2) AF organization and fibrosis are related at the smallest scale whereas AF and Cx43 at the largest scale only. (3) Tissue anisotropy is a major factor in structure function relationships. (4) Fractionated Egs are not summated individual action potentials. (5) Accurate co-localisation and annotation are critical to identifying subtle structure function relationships and may be the limiting factor in human studies.

15–12 Abstract 17–17

145 ANTIARRHYTHMIC EFFECT OF THE CONSECUTIVE ISOPROTERENOL/ADENOSINE TREATMENT DURING REGIONAL ISCHAEMIA.

Igor Khaliulin¹, Andrew F. James¹, M.-Saadeh Suleiman¹

¹ University of Bristol, Bristol, UK

Background: We have recently found that consecutive isoproterenol/adenosine treatment (Iso/Ade), mediated by the consecutive activation of cAMP-PKA and PKC signalling pathways, is a potent cardioprotective pharmacological intervention, which significantly reduces necrotic damage and improves haemodynamic function recovery after global ischaemia. However, this intervention had no significant effect on the reperfusional arrhythmias after global normothermic ischaemia. The purpose of the present study was to assess the effects of Iso/Ade on cardiac function, including ventricular arrhythmias, and necrotic damage during regional ischaemia and reperfusion. Methods: Experiments were performed on isolated Lengendorff-perfused rat heart. All hearts were subjected to 30-min regional ischaemia and 2-h reperfusion. Regional ischaemia was induced by occlusion of the left anterior descending coronary artery (LAD). The hearts were divided into control and Iso/Ade groups according to the preischaemic protocol. Hearts of the Iso/Ade group were perfused with 10 nM isoproterenol for 2 min followed by 5 min perfusion with 30 μM adenosine. Electrocardiogram (ECG) and left ventricular pressure were monitored throughout the experiment. Ventricular arrhythmias (number of ventricular premature beats (VPBs), number and total duration of ventricular tachycardia and ventricular fibrillation (VT and VF)) were assessed using ECG. At the end of reperfusion, infarct size-to-area at risk ratio (IS/AAR) was determined in the hearts. In a separate series of experiments, mitochondria were isolated from Iso-perfused and control hearts, and the ability of mitochondria to retain Ca2+ was assessed fluorimetrically. Results: During LAD occlusion, arrhythmias were dramatically reduced in the treated hearts. Thus, in the control and Iso/Ade groups, the number of VPBs were 678 ± 172 vs. 135 ± 39, the number of VT and VF were 91 ± 24 vs. 7 ± 3, and the total duration of VT and VF were 243 ± 85 vs. 3 ± 1 s, respectively. During reperfusion, the number of VPBs was similar in the two groups. However, the number and duration of VT and VF were still significantly lower in the Iso/Ade group. Iso/Ade also considerably improved hemodynamic function recovery and reduced IS/AAR during reperfusion. Interestingly, that perfusion of hearts with Iso significantly enhanced ability of mitochondria to retain Ca2+. Conclusion: Thus, in contrast to the global ischaemia, consecutive isoproterenol/adenosine treatment effectively prevented the development of ventricular arrhythmias during regional ischaemia and reperfusion. This treatment also significantly improved functional recovery and reduced infarct size after the LAD ligation. This effect could be a result of the improved Ca2+ handling by the myocardium in the treated hearts during regional ischaemia and reperfusion.

15–13 Abstract 19–19

146 ASSOCIATION OF TERC RELATED GENETIC VARIATION AND TELOMERASE ACTIVITY WITH VENTRICULAR ARRHYTHMIAS IN ISCHAEMIC CARDIOMYOPATHY

Vinit Sawhney¹, Scott Brouilette², Niall Campbell¹, Steven Coppen², Victoria Baker¹, Claire Kirkby¹, Ross Hunter¹, Mehul Dhinoja¹, Mark Earley¹, Simon Sporton¹, Ken Suzuki², Richard Schilling¹

¹ St Bartholomew’s hospital, London, UK; ² William Harvey Heart Centre, London, UK

Introduction: Implantable cardioverter defibrillators (ICD) reduce mortality in ischaemic cardiomyopathy patients at a high risk of ventricular arrhythmias (VA). However, ICDs are associated with morbidity and mortality. There is need for better risk stratification. Telomere and telomerase activity (TA) in leukocytes have recently been shown to correlate with biological ageing and pathogenesis of cardiovascular diseases. Telomerase maintains telomere length and is composed of a reverse transcriptase, TERT, and an RNA template, TERC. Evidence suggests that genetic variation in key genes has a key impact on TA. Association of SNP12696304 on chromosome 3q26 (at a locus that includes TERC) with telomere length has been shown. We investigated the association between genetic variation in SNP12696304 and leukocyte TA with incidence of VA in ischaemic cardiomyopathy patients. Methods: Ninety ischaemic cardiomyopathy patients with primary prevention ICDs were recruited. Genomic DNA was isolated from venous blood samples. TA was measured telomere repeat amplification (TRAP) protocol and genotyping by Taqman SNP assay. Logistic regression was used to determine correlation of genotype and TA with VA. Results: There was no significant difference in baseline demographics including age, sex, lvef, and follow-up since ICD implant between patients with VA (cases, n = 35) and no-VA (controls, n = 55). TA was significantly higher in the cases and correlated with incidence of VA (p value 0.02). No significant correlation between the genotype and VA was identified (C/C OR 1; C/G OR 0.54, p value 0.343; G/G OR 0.80, p value 0.907). There was a significant correlation between risk of VA and TA increase in C/C genotype only (OR 7.5, CI1-56.6, p value 0.04) as shown in Figure 1. Conclusion: There is a significant correlation between TA and VA in ischaemic cardiomyopathy patients. Moreover, homozygosity for C allele of SNP 12696304 (encoding TERC) significantly effects telomerase expression. Thus, increased TA predisposes individuals with C/C genotype to a higher incidence of VA

15–14 Abstract 01–15

147 THE QT INTERVAL INCREASES WITH DECREASING PLASMA POTASSIUM IN THE DANISH GENERAL POPULATION

Jorgen Kanters¹, Claus Graff², Jimmi Nielsen², Lise Henriksen¹, Anne Sofie Petri¹, Michael Christiansen³, Jan Kvetny⁴, Christina Ellervik⁴

¹ University of Copenhagen, Copenhagen N, Denmark; ² Aalborg University, Aalborg, Denmark; ³ Statens Serum Institut, Copenhagen, Denmark; ⁴ Næstved Hospital, Næstved, Denmark

It is well known that hypokalemia is associated with prolonged QT interval. However, the relation between plasma potassium and the QT interval has not been established in a general population. Methods: As part of the Danish General Suburban Population Study (GESUS) in Naestved Municipality, a general population cohort was established. We examined 8779 individuals with digitally recorded ECGs on a MAC5000 (GE Healthcare, Milwaukee). QT and RR intervals were measured by the 12SL algorithm (GE Healthcare, Milwaukee, WI) and corrected with both Fridericia (QTcF) and Bazetts (QTcB) method. Persons with cardiovascular disease, diabetes, increased creatinine (>95 % percentile for gender and age) or pulmonary disease were assumed non-healthy, whereas the rest were assumed to be healthy. Statistics are given as mean ± SE or as 95 % confidence Interval. Results: QTcF was univariately correlated to potassium concentration r ² = 0.0. The relation was nicely linear even in the extremes of potassium concentration (range 2.7–4.9 mM). As seen in Table 1, assumed healthy subjects had slightly shorter corrected QT intervals and longer mean RR intervals than non-healthy. The corrected QT interval depended in a multivariate interval on age, sex and Se-potassium.

Mean ± SD		Full cohort	Assumed non-healthy	Assumed healthy
Demographics
n		8779	3438	5341
Age	years	56.45 ± 13.53	64.11 ± 11.62*	51.52 ± 12.32
Male	%	45.8 %	47.1 % (p = 0.052)	45.0 %
ECG parameters
QTcF	ms	416.5 ± 20.4	420.5 ± 21.8*	413.9 ± 19.0
QTcB	ms	420.9 ± 24.5	427.7 ± 25.2*	416.4 ± 22.9
RR	ms	956.0 ± 163.9	918.6 ± 159.8*	980.2 ± 162.0
Clinical chemistry
Se-Potassium	mM	3.883 ± 0.297	3.894 ± 0.342*	3.876 ± 0.264
Se-Sodium	mM	140.70 ± 2.24	140.52 ± 2.52*	140.82 ± 2.03
Creatinine	μM	77.39 ± 19.42	80.94 ± 25.45*	75.14 ± 13.83

Table 1. *p < 0.0001

QTcF	Univariate a	95 % CI	Multivariate a	95 % CI
Age (years)	0.21*	[0.17; 0.25]	0.26*	[0.21; 0.30]
Gender (M vs. F)	−7.4*	[−8.4;−6.4]	−6.7*	[−7.7; −5.7]
Se-potassium (mM)	−8.4*	[−10.3;−6.4]	−8.3*	[−10.2;−6.3]
Se-sodium (mM)	0.12	[−0.12; 0.38]
Creatinine (μM)	−0.17	[−0.21; −0.14]
Intercept			436*	[429; 443]

Table 2. *p < 0.0001. Conclusion: The corrected QT interval increases with 8.4 ms/mM decrease in potassium nearly independent of age and gender. Since FDA has a threshold of concern of DQTc = 5 ms, it seems necessary to take plasma levels of potassium into account when analyzing data in studies on drug-induced QTc- prolongation.

15–15 Abstract 04–10

148 LOCALISATION OF GANGLIONIC PLEXI SITES WITHIN THE LEFT ATRIUM

Belinda Sandler¹, Nick Linton¹, Michael Koa Wing¹, Saj Hayet¹, Norman Qureshi¹, Vishal Luther¹, Nicholas Peters¹, Wyn Davies¹, Louisa Malcome Lawes¹, Boon Lim¹, Prapa Kanagaratnam¹

¹ Imperial College London, London, UK

Background: The autonomic nervous system has been implicated in the pathogenesis of AF. High-frequency stimulation (HFS) can be used to identify endocardial ganglionated plexi sites. We studied the left atrial distribution of these sites in patients undergoing ablation for AF. Methods: Synchronised HFS delivering 15 V at 20 Hz was performed through a CARTO Smart Touch catheter during fixed rate pacing within the local refractory period (100 ms post-pacing spike). A positive site was a location where HFS produced either ectopy or AF reproducibly. A negative site was defined as a location where HFS did not initiate AF/ectopy. All sites were tagged using 3D geometry for analysis. Systematic testing was done throughout the left atrium. Results: Six patients were recruited. The mapping time was 76.3 ± 14 min with 80 ± 17 locations tested per patient. There were 19 ± 6 positive sites and 61 ± 25 negative HFS sites per patient. The positive HFS sites were located at the PV antrum in 10 ± 3 sites and non-antral regions were in 9 ± 4, respectively. Chi-squared analysis indicated no difference between antral and non-antral regions (p = 0.19). In the non-antral regions, 22/56 (39.2 %) sites were on the roof, 16/56 (28.6 %) at the septum and 18/56 (32.1 %) on the posterior wall. Conclusion: This study suggests that GP sites that trigger ectopy are not confined to the PV antrum as suggested by post-mortem studies.

Poster session C part 2: Sudden cardiac death and implantable cardioverter defibrillator

Monday, April 20, 2015

Posters exposed from 8:30 AM to 12:00 PM

Presenters and chairpersons present from 10:30 AM to 12:00 PM

15–16 Abstract 19–17

149 SUDDEN CARDIAC DEATH IN YOUNG WOMEN IN DENMARK

Bo Gregers Winkel¹, Bjarke Risgaard¹, Reza Jabbari¹, Thomas Hadberg Lynge¹, Charlotte Glinge¹, Henning Bundgaard¹, Stig Haunsø¹, Jacob Tfelt-Hansen¹

¹ Rigshospitalet, department of Cardiology, Copenhagen, Denmark

Introduction: Hitherto, sudden cardiac death (SCD) in the young—defined as SCD in 1–35 years old—has been described with no distinction between genders. Most data suggest a lower incidence rate of SCD in young women (SCDw) than in men (SCDm). However, causes of SCDw, as well as autopsy rates, and prior known disease have not been systematically investigated in a nationwide setting before. Methods: All deaths in persons aged 1–35 years in Denmark in 2000–2009 were included. To chart causes of death and incidence rates, death certificates, and autopsy reports were collected and read. By additional use of the extensive health care registries in Denmark, we were also able to investigate prior disease. SCDw were compared to SCDm. Results: During the 10-year study period, there was an average of 2.37 million persons aged 1–35 years (49 % women). There were a total of 8756 deaths from 23.7 million person-years. Of these, 10 % (n = 848) were sudden unexpected deaths. In total, 635 of sudden unexpected deaths were SCD, of which SCDw constituted 205 deaths (32 %). Compared to SCDm, women less often died in a public place (16 vs 26 %, p = 0.02). Women more often died during sleep, and less often during moderate- to high-intensity activity (40 and 3 vs 33 and 11 %, respectively, p = 0.036). There were no differences between genders in regard to age at death, witnessed deaths, ratio of autopsies, and ratio of sudden unexplained deaths. Likewise, there were no differences in comorbidity between SCDw and SCDm. Most common structural heart diseases in SCDw were ischemic heart disease (n = 17, 13 % of autopsied SCD), followed by myocarditis and ARVC (n = 9 each, 7 % of autopsied SCD). In the subgroup of SCD in children (1–18 years), females were less often autopsied (62 vs 81 %, p = 0.027). The incidence rate of SCDw was half of that of SCDm (1.8 vs 3.6 per 100,000 person-years, Incidence rate ratio 2.0 (95 % CI 1.7–2.4), p < 0.01). Conclusions: This nationwide study describes SCD in young women and gender differences. Young women only die half as often from SCD than young men. Causes of death were largely comparable with SCDm. Women die more often during sleep and less often during sports activity. This study will help better understand the role of gender in SCD in the young and put forward attention on the importance of these deaths being properly investigated by autopsy. This will help the subsequent familial cascade screening.

15–17 Abstract 19–21

150 SUDDEN CARDIAC DEATH PROTOCOL ANALYSIS OF POSTMORTEM AUTOPSIES

Sergey Mikhaylichenko¹, Vladimir Gorbunov², Egor Bogatikov², Maxim Mikhaylichenko²

¹ Bakoulev Center for Cardiovascular Surgery, Moscow, Russia; ² Chita State Medical Academy, Chita, Russia

Sudden cardiac death (SCD) occurs in case of various heart diseases, as well as in different types of arrhythmia. According to different studies, in all causes of death, the SCD rate is about 40 %. In all cases of SCD, less than 10 % of patients get hospitalized (less than 40,000); half of the patients die before discharge from the hospital (20,000); 20,000 patients stay alive but need treatment. Aim of study. To analyze cases of sudden cardiac death in Chita Area, Russia; to identify the percentage of the patients died suddenly of cardiovascular disease in the mortality structure in Chita Area in 2013; to evaluate the gender, age profile of the patients who died suddenly; to identify possible causes of sudden cardiac death; and to assess possible impact of alcohol on the risk of sudden cardiac death. Content and methods. Analysis of 500 postmortem autopsy protocols of cardiovascular disease cases in Chita in 2013. Statistical analysis was carried out by continuous sampling. Results. The postmortem autopsies analysis of patients died of cardiovascular disease in Chita Area in 2013 proved that 22 % of patients died suddenly. The average age was 54.3 ± 10.9 years. Of those who died suddenly, the largest percentage are males (78 %). It was found that 16 % of patients misused alcohol. The main cause of sudden cardiac death is coronary artery disease. Atherosclerotic coronary vessels disease was found in 88 % of cases. Dilatation of the left ventricle was stated in 12 % of deaths, 3 % had hypertrophic cardiomyopathy, hypertrophy of the left ventricle was found in 43 % of suddenly died. Among pathological diagnosis, 64 % was acute coronary insufficiency. Nineteen percent of the causes of death was a myocardial infarction of different localization. Eight percent of cases the cause of sudden cardiac death was defined as alcoholic cardiomyopathy. Conclusions. According to the study, a large percentage of sudden cardiac death cases are patients of working age (22 %). Males are in the greater risk of SCD. The main cause of sudden cardiac death is coronary heart disease. Alcoholic cardiomyopathy takes up a large percentage in SCD structure in Chita Area. The reports of autopsies prove that clinical diagnosis of sudden cardiac death was not identified in 98 % of cases.

15–18 Abstract 31–15

151 CLINICAL CHARACTERISTICS AND EVOLUTION OF PATIENTS WITH AN IMPLANTABLE CARDIOVERTER DEFIBRILLATOR THAT HAVE BEEN TRANSPLANTED.

Francisco Méndez Z¹, Enrique Rodriguez¹, Concepción Alonso¹, José Guerra¹, Eulalia Roig¹, Sonia Mirabet¹, Marcos Rodríguez G¹, Xavier Viñolas P¹

¹ Hospital de la Santa Creu i Sant Pau, Barcelona, Spain

INTRODUCTION. A high proportion of patients eligible for cardiac transplant (CT) also met criteria for an implantable cardioverter defibrillator (ICD). In Spain, 5 % of the patients die during the waiting time of a CT. The aim of this study was to evaluate the clinical characteristics, safety and therapies of patients with an ICD who were later transplanted. METHODS. Retrospective study. We included all patients with an ICD implanted in our center since 1998, which later received a CT. Clinical and echocardiographic characteristics, time from implant to CT, appropriate and inappropriate therapies, device related complications and mortality were analyzed. RESULTS. A total of 1132 ICD patients were evaluated. Fifty-nine patients (5.21 %) received a CT (age 52.2 ± 10.1 years, 83.1 % male). The cardiac etiology was ischemic in 39 % and non-ischemic in 44 %. The indication for primary prevention ICD was 64.4 %. The time from implant to CT was significantly lower in patients with primary prevention (773 vs. 982 ± 1607 ± 1461 days, p = 0.043). During this period, 39 % of patients received at least one appropriate therapy (31 % in primary prevention and secondary prevention 55 %, p = 0.064). Seventeen percent of patients received at least one inappropriate therapy (15 % primary and 20 % secondary prevention, p = 0.72). CONCLUSION. Among patients with an ICD who receive a CT, the percentage of appropriate therapies is high, particularly in patients with secondary prevention indication. The time to transplant is lower in patients with primary prevention. A low percentage of patients with ICD in our series received a CT. Table 1. Evolution of trasplanted patients according ICD indication

	Primary prevention	Secondary prevention	p value
Waiting time until CT (days)	982 ± 773	1607 ± 1461	0.043
Appropriate therapy	12/39	11/20	0–064
Inappropriate therapy	6/39	4/20	0.72

15–19 Abstract 25–10

152 IS IMPLANTABLE CARDIOVERTER-DEFIBRILLATOR REPLACEMENT NECESSARY IN THE PRIMARY PREVENTION PATIENT WHOSE LEFT VENTRICULAR EJECTION FRACTION HAS NORMALIZED?

JoEllyn Abraham¹, Deepa McGriff¹, C. Dennis O’Hare², Raed Abdelhadi¹, Jay Sengupta¹, Robert Hauser¹

¹ Minneapolis Heart Institute, Abbott Northwestern Hospital, part of Allina Health, Minneapolis, MN, USA; ² Abbott Northwestern Hospital, part of Allina Health, Minneapolis, MN, USA

Background: There are limited data on the need for implantable cardioverter-defibrillator (ICD) pulse generator (PG) replacement in primary prevention patients who have not received appropriate ICD therapy (ICD-Rx) and whose left ventricular ejection fractions (LVEF) have normalized. Accordingly, we assessed the outcomes of such patients at our center who did and did not undergo ICD replacement for battery depletion. Methods: This was a single-center retrospective study. Patients were age ≥18 years who had ischemic cardiomyopathy (ICM) or dilated cardiomyopathy (DCM) and who underwent primary prevention ICD implantation from 2000 to 2014. Patients who had received ICD-Rx for ventricular tachycardia (VT) or ventricular fibrillation (VF) were excluded. Results: The cohort included 82 patients (average age 65 ± 12 years; 66 % male) whose average LVEF was 24.2 ± 7.0 % at initial ICD implant (range 10–37 %) and 49.3 ± 3.9 % (range 45–55 %) when their PGs reached end-of-battery life. None had received ICD-Rx for VT or VF. The majority of patients had DCM (n = 48; 59 %) and the remaining patients had ICM (41 %). Of the 82 patients, 72 (88 %) underwent ICD replacement, 6 (7 %) were “downgraded” to a pacemaker, and 4 (5 %) patients had their ICDs removed or abandoned. During average follow-up of 19 ± 14.3 months, nine patients died, including seven in the replacement group, and one each in the pacemaker and removed/abandoned groups. No death was sudden or primarily arrhythmic. Four of 72 patients (5.6 %) in the ICD replacement group received appropriate device therapy for VT (n = 3) or VF (n = 1); two of these patients had DCM and two had ICM with %LVEFs of 60, 50, 45, and 45, respectively. Conclusions: These data suggest that LVEF normalization is not associated with complete freedom from VT/VF in primary prevention patients who present for elective ICD replacement. However, the risk of mortality/morbidity for such patients and the need for ICD-Rx appears to be low.

15–20 Abstract 25–11

153 IMPLANTED CARDIOVERTER DEFIBRILLATOR SHOCK RISK AND MORTALITY IN WOMEN WITH ADRIAMYCIN-INDUCED CARDIOMYOPATHY

Marc Lahiri¹, Arfaat Khan¹, Gurjit Singh¹, Claudio Schuger¹

¹ Henry Ford Hospital, Detroit, MI, USA

Background: The benefit of implanted cardioverter defibrillators (ICDs) for primary prevention of sudden death is established in patients with nonischemic dilated cardiomyopathy (NIDCM). However, frequency of ICD shocks and survival is unknown in the subset of such patients with adriamycin-induced cardiomyopathy (A-CM). Methods: Retrospective case control analysis was performed on 15 women with A-CM with primary prevention ICD implanted at Henry Ford Hospital from 2001 to 2012. Shocks were adjudicated by trained electrophysiologists. Wilcoxon and chi-squared tests were used to analyze continuous and nominal variables between the study group and a control of 60 women with ICD for “traditional” non-adriamycin NIDCM. Negative binomial modeling was used to analyze incidence of shocks delivered for the study vs. control groups. Results: Subjects and controls were well matched in demographics (table), follow-up duration, baseline left ventricular ejection fraction, and therapy rate cutoff. Women with A-CM were less likely to receive a shock than controls (rate ratio 0.06, p = 0.038) with a trend toward less appropriate shocks (rate ratio 0.13, p = 0.115). However, there was a near-significant trend toward higher mortality in the A-CM group vs. control (40 vs 15 %, p = 0.06). Conclusion: Women with ICDs for Ad-CM are less likely to receive shocks than those with “traditional” NIDCM, but have a nearly significant trend toward higher mortality. Further study is needed to determine the efficacy and appropriateness of primary prevention ICD use in women with A-CM.

	Adriamycin cardiomyopathy (n = 15)	Control group (n = 60)	p value
Demographics/baseline characteristics
Age (years)	63.5 ± 11.7	59.2 ± 12.9	0.33
LVEF at implant (%)	22.5 ± 6.9	22.5 ± 9.6	0.77
Months of follow-up	33.1 ± 22.6	34.3 ± 30.7	0.76
Clinical events
Patientss with appropriate shocks (%)	1 (6.7 %)	10 (16.7 %)	0.45
Mortality (%)	6 (40 %)	9 (15 %)	0.06

15–21 Abstract 19–10

154 INAPPROPRIATE SUBCUTANEOUS IMPLANTABLE CARDIOVERTER DEFIBRILLATOR SHOCKS DUE TO T-WAVE OVERSENSING CAN BE PREVENTED.

Kirsten M. Kooiman¹, Reinoud E. Knops¹, Louise R. Olde Nordkamp¹, Arthur A. Wilde¹, Joris R. de Groot¹

¹ Academic Medical Centre, Amsterdam, Netherlands

Introduction: Inappropriate shocks (IAS) complicate implantable cardioverter defibrillator (ICD) therapy. The management of IAS in patients with a subcutaneous ICD (S-ICD) differs from conventional ICDs because of different sensing and programming. We describe the management of IAS in patients with a S-ICD. Methods: Patients were implanted with a S-ICD 2009 and 2012. The prevalence and clinical determinants data of IAS were prospectively collected. In case of T-wave oversensing (TWOS), an exercise test was performed, and all possible sensing vectors were screened on TWOS. Absence of TWOS defined a suitable vector. Results: Eleven out of 69 patients (54 % male, age 39 ± 14 years, 73 % primary prevention) received IAS after 8.9 ± 10 months following implantation (10.8 % annual incidence rate). Bundle branch block or digoxin use was associated with IAS. In eight cases, TWOS caused IAS. Seven of these occurred during exercise and one during atrial fibrillation with a high ventricular rate, and an exercise test was performed. Additionally, in seven patients, the sensing vector and in five patients the (un)conditional zone was changed. Hereafter, IAS recurred in three of these 11 patients, in two due to human error. After optimization we observed no IAS during a follow-up of 14.1 ± 13 months. Conclusion: IAS due to TWOS in the S-ICD can be managed with reprogramming the sensing vector and/or the therapy zones of the device using a template acquired during exercise. Exercise-optimized programming can reduce future IAS, and standard exercise testing shortly after implantation of a S-ICD may be considered in patients at risk for TWOS.

15–22 Abstract 19–18

155 SUB-MAMMARY ICD IMPLANTATION: LEAD CHARACTERISTICS, LONGEVITY, AND COMPLICATIONS. A RETROSPECTIVE REVIEW.

Nicole E Worden¹, Lee Joseph¹, Chad C Ward¹, Samih L Khauli¹, Brodie R Marthalar¹, Musab N Alqasrawi¹, Michael C Giudici¹

¹ University of Iowa Hospitals and Clinics, Iowa City, AI, USA

Introduction: Infra-clavicular device implantation is standard. However, female patients can find this location troublesome. Devices rub against purse straps, seatbelts, and undergarments and can interfere with psychosocial functioning. Previous reports show significant satisfaction with sub-mammary device implantation. Lead longevity, characteristics, and complications have not been reported in a sizeable cohort. We hypothesized that lead pacing thresholds, intrinsic amplitudes, impedances, lead malfunction, ICD discharges, and peri-procedural complications would be similar to previously reported values at implant and most recent follow-up. Methods: We retrospectively reviewed medical records for demographic, medical, outcome, and complication data for patients who received sub-mammary ICD implantation between 01/01/1995 and 11/01/2014. Results: Thirty female patients underwent sub-mammary device implantation. They were followed for an average of 27.5 (20–101.8) months. Sixty percent of the patients had hypertension, 43 % had non-ischemic cardiomyopathy. The majority of the devices were implanted for primary prevention (66.7 %) due to hypertrophic cardiomyopathy, non-ischemic cardiomyopathy, and cardiac resynchronization therapy among others. Secondary prevention devices were 13.3 % of implantations. Indications for a secondary prevention device included the following: arrhythmogenic right ventricular dysplasia and ventricular tachycardia. Three patients received pacemakers for sick sinus syndrome, neurogenic syncope, or atrial arrhythmia. Capture threshold and intrinsic amplitude for the atrial lead was not significantly different between implantation and most recent interrogation. Atrial lead impedance was significantly less at follow-up (p = 0.04) although both were within the clinically acceptable range. Right ventricular lead baseline thresholds were significantly less than the most recent follow-up threshold (p = 0.000). Intrinsic amplitude for the right and left ventricular leads was not significantly different over time. Decrease in right ventricular lead impedance over time was significant (p = 0.018). None of the lead characteristics in the left ventricular leads were significant over time. Defibrillation impedance was significantly higher at follow-up (p = 0.01) although still within the clinically acceptable range. There were six complications including the following: one lead dislodgement (3.3 %), two device infections (6.7 %), and three explantations related to the previously mentioned complications. Two patients had appropriate shocks and one patient had an inappropriate shock. Conclusion: Sub-mammary device implantation is a durable alternative to traditional infra-clavicular device implantation as demonstrated by lead characteristics at implantation and follow-up which were well within the acceptable clinical range. There was only one case of lead dislodgement. There was higher percentage of infections than is typical. Prospective studies are needed to further elucidate lead performance and complications when placed in the sub-mammary location.

15–23 Abstract 19–20

156 INFLUENCE OF TELEMONITORING SYSTEMS ON QUALITY OF LIFE AND DEVICE-ACCEPTANCE IN PATIENTS WITH IMPLANTABLE CARDIOVERTER-DEFIBRILLATORS – 12 MONTHS FU DATA

Johannes Siebermair¹, Eimo Martens¹, Florian Leppert², Stefanie Fichtner¹, Stefan Sattler¹, Heidi Estner¹, Regina Freeden³, Alexander Balke³, Josef Lauter³, Wolfgang Greiner², Reza Wakili¹, Stefan Kääb¹

¹ Medizinische Klinik und Poliklinik I, LMU Klinikum der Universität München, München, Germany; ² Fakultät für Gesundheitswissenschaften, Universität Bielefeld, Bielefeld, Germany; ³ Medtronic, Meerbusch, Meerbusch, Germany

INTRODUCTION: Telemonitoring systems (TMS) for ICDs are gaining attention as a strategy to optimize patient care and to save costs. OBJECTIVES: This study prospectively investigated the influence of telemonitoring on the levels of depression, QoL and device acceptance in ICD patients over a period of 12 months. METHODS: In this prospective controlled randomized single-center trial, 180 patients (82 % male; age 62.9 ± 14.8; 47 % with coronary artery disease, 37 % with dilated cardiomyopathy, NYHA class 2.0 ± 0.7) were randomized at the day of ICD implantation to either telemonitoring (n = 91) or control group (n = 89). Patients in the intervention group were equipped with a telemonitoring system. In the control group, only conventional in-office follow-up (FU) visits were performed. Patients had to fill out three questionnaires at baseline; patients were followed up for 12 months, with postal surveys on a monthly basis. RESULTS: One hundred fifty-three patients finished at least the 3-month questionnaire and were included in the further analyses. The telemonitoring group showed a mean improvement in the health-related QoL (EQ-5D-Index) by 8.62 points compared to baseline levels after 12 months (p = .0234), while the QoL levels in the control group did not differ significantly vs. baseline over time (see figure). However, FPAS and HADS-D showed only a positive non-significant trend for beneficial effects for the telemonitoring group concerning device-acceptance and level of depression, respectively. CONCLUSIONS: Our results suggest that the use of TMS seems to improve QoL of ICD patients over time. In addition, the results indicate marginal effects on the levels of depression, anxiety, and device acceptance, which have to be further validated by in larger patient cohorts with longer FU periods.

15–24 Abstract 19–22

157 REDUCTION OF INAPPROPRIATE THERAPIES: REMOTE MONITORING FOLLOW-UP OF 387 CRT-D

Peggy Jacon¹, Alix Martin¹, Natacha Pellet¹, Hager Rekik¹, Jean Jacques Ndjessan¹, Pascal Defaye¹

¹ CHU Grenoble, Grenoble, France

Purpose: Remote monitoring (RM) is now accepted as a safe alternative to standard follow-up (sFU) for ICD. Methods: We analyzed the long term arrhythmic events and device-related outcomes in the specific setting of CRT-D. Patients (pts) were equipped with Boston (52 %), Medtronic (36 %), St Jude Medical (10 %), Biotronik (1 %) and Sorin (1 %) RM systems. FU started after hospital discharge. Automatic FU with RM was performed every 3 months, with at least one sFU/year. In emergency cases, pts were invited for in-hospital control visits. ICDs were programmed with two zones (VT zone >180 bpm/VF zone > 220 bpm). All RM alerts and related EGMs as well as the reasons of therapies were reviewed by two physicians Results: Three hundred eighty-seven pts (83 % male, 67 ± 9 year olds) were enrolled. Forty-six percent had ischemic cardiomyopathy, 43 % previous history of AF. Seventy-eight percent were primary prevention ICDs. During a FU period of 32 ± 12 months, we noted 18 ± 14 automatic RM FU and 2 ± 1 sFU visits/patient. Fifty-two pts died during FU. Fifty-five pts had major alerts (26 for ICD lead dysfunction, 15 for ERI reached, 12 for electrical storm, two therapies off). Within 157 pts with minor alerts, 78 refers to AF, with for 28 pts early detection of unknown AF resulting in therapy modifications. One hundred one appropriate (app) shocks occurred in 33 pts (9 %). Thirty-two inappropriate shocks occurred in 11 pts (3 %) and were mainly due to AF (64 %, other: sinus tachycardia 18 %, lead dysfunction 9 %, T oversensing 9 %). Sixty-five pts had app ATP (17 % of the population). Fourteen pts with high LV lead impedance detected by RM had LV lead dislodgement and underwent early intervention. Conclusion: In a large single-center observational study, RM has demonstrated to be an effective method of FU for ICD-CRT recipients. Early diagnoses of AF or lead failure allow rapid management of patients and are associated with a very low rate of inappropriate shocks

15–25 Abstract 19–23

158 DEFIBRILLATION THRESHOLD TESTING—IS IT STILL NECESSARY FOR ANY PATIENT SUBGROUP? A LARGE REAL LIFE ANALYSIS

Eimo Martens¹, Johannes Siebermair¹, Regina Freeden², Carsten Koenig², Stefan Veith¹, Moritz Sinner¹, Stefan Kääb¹

¹ Klinikum der Universität Muenchen, Muenchen, Germany; ² Medtronic GmbH, Meerbusch, Germany

Background. Defibrillation threshold (DFT) testing for ICDs is an established procedure to assess the ICD’s ability to terminate VF or VT. DFT-testing is controversially discussed in the literature and is performed differently depending on the implanting facility. Several factors have been described affecting the success of DFT-testing. In fact, no survival benefit was shown if testing was performed or not. Predictors for the success of DFT-testing remain incompletely understood. Objective. The study aims to retrospectively investigate the DFT-test success or failure in dependence of disease, type of prevention and ejection fraction. Methods. Anonymized follow-up data of ICD and CRT-D of the time between 2002 and 2013 were collected and pooled from our clinic. Data were analyzed in a database that allows the collection of follow-up from ICD programmer as well as telemedicine transmissions. Within the database, all parameters as well as EGMs, episode and patient data are stored and can be analyzed. The occurrence of successful vs. unsuccessful DFT-test was classified by trained physicians. Results. Data were analyzed from 8300 follow-ups of 704 patients (952 ICD/CRT-D devices). We specified 79 % male, mean age 66 ± 13 years, 62.7 % primary prevention, 55 % ICM, 39 % DCM and 6 % other diseases. The cohort encompassed 446 (47 %) single chamber, 232 (24 %) dual chamber, and 274 (29 %) three chamber devices. The devices’ shock energy was 35 J (n = 746), 34 J (n = 7, models included 7221 and InSync), or 30 J (n = 199). During the implantation procedures, 238 DFT-tests were performed (25 %) with a mean safety-margin of 11.69 J. Thereof, 165 tests had stored electrograms available for the assessment of success. DFT-tests with available electrograms were performed with 15 J (n = 11 (6.8 %)), 20 J (n = 43 (25.9 %)), 35 J (n = 96 (58.0 %)), 30 J (n = 2 (1.3 %)), and 35 J (n = 13 (7.9 %)). The mean RV-shock-impedance was 55Ω in the test-group and 56Ω in the no-DFT-test-group (not significant). In 12 (7.5 %) cases, we adjudicated DFT-test-failure. All test-failures occurred with 35-J devices. For the test failures, there was no statistically significant difference between primary or secondary prevention as well as different diseases or ejection fraction. Conclusion. DFT-testing is still controversially discussed. In our cohort, DFT-testing failure was a rare but relevant problem. In our analysis, clinical parameters have no influence of success or failure of DFT-Test. Further data is necessary to identify other relevant predictors of DFT-test failure.

15–26 Abstract 19–28

159 PROJECTED NUMBERS OF REPLACEMENTS REQUIRED DURING NATURAL LIFESPAN OF CRTD/ICD RECIPIENTS

Ernest Lau¹, Eric Hammill², Nicholas Wold²

¹ Royal Victoria Hospital, Belfast, UK; ² Boston Scientific Corp, St Paul, MN, USA

Introduction: Patient life expectancy and device longevity together determine the number of replacements required during the natural lifespan of CRTD/ICD recipients. Device longevity can be extended by increasing the battery capacity, at the expense of a larger can size. An attempt was made to define the optimal device longevity based on the known life expectancy of CRTD/ICD recipients by age at first implantation. Methods: The Device Tracking Database at Boston Scientific was interrogated for patients implanted with a CRTD (>115,000) or an ICD (>300,000) over 18 years between 1993 and 2011. The life expectancy of the cohort up to 1/1/2012 stratified by age at first implantation was used to project the numbers of replacements required for different device longevities during the lifespan of CRTD/ICD recipients (based on the 25 % percentile of life expectancy). Results: CRTD/ICD recipients < 40 years at first implantation had life expectancy ≥30 years, requiring 2–7 CRTD or 1–4 ICD replacements during their lifespan with contemporary device longevities. Recipients >70 years at first implantation had life expectancy ≤10 years. Device longevities of 9 years and 12 years for CRTD and ICD, respectively, will eliminate replacement for >75 % of patients during their natural lifespan. Conclusions: Based on actuarial data, longevity of 9 and 12 years for CRTDs and ICDs, respectively, may strike a reasonable balance between avoidance of device replacement and can size for patients >70 years old.

15–27 Abstract 19–29

160 IMPLANTABLE CARDIAC DEFIBRILLATOR AMONG ADULTS WITH TRANSPOSITION OF THE GREAT ARTERIES AND ATRIAL SWITCH OPERATION

Abdeslam Bouzeman¹, Eloi Marijon¹, Maxime De Guillebon², Magalie Ladouceur, Guillaume Duthoit³, Raphael Martins⁴, Pierre Bordachar², David Celermajer⁵, Jean-Benoit Thambo², Laurence Iserin¹, Nicolas Combes⁶

¹ European Georges Pompidou Hospital, Cardiology Department, Paris, France Paris Cardiovascular Research Center, Paris, France; ² CHU Haut Leveque, Cardiology Department, Bordeaux, France; ³ CHU La Pitie Salpetriere Hospital, Cardiology Department, Paris, France; ⁴ CHU Pontchaillou, Cardiology Department, Rennes, France; ⁵ Sydney Medical School, Sydney, Australia; ⁶ Clinique Pasteur, Toulouse, France

Background—The experience with the implantable cardiac defibrillator (ICD) in patients with transposition of the great arteries (TGA) and history of atrial switch surgery remains limited. Methods—Retrospective evaluation aiming to assess characteristics and outcomes of consecutive TGA patients with history of atrial switch surgery implanted with an ICD between January 2005 and June 2012 in four French centers. Results—Of the 12 patients (median 34 years [28, 40]; 67 % male), four patients (33 %) were implanted for secondary prevention after symptomatic documented sustained ventricular tachycardia or sudden cardiac arrest. ICDs were implanted for primary prevention in 8 patients (67 %), including cardiac resynchronization in three patients; severe systemic ventricle dysfunction was present in all cases (median ejection fraction 27 % [20, 40]). Overall, one patient died during the ICD implantation secondary to refractory cardiac arrest after defibrillation testing. Over a median follow-up of 19 months [10, 106], six patients out of 11 (54 %) experienced worsening of congestive heart failure, including five who were eventually transplanted. Overall, three patients (27 %) experienced significant ICD-related complications, whereas only one patient (primary prevention indication) developed appropriate ICD therapy (successful anti-tachycardia pacing without shock). Half of patients presented with at least one episode of sustained (≥5 min) atrial arrhythmia during follow-up. Conclusions—Our findings underline the key role of progressive heart failure in dictating outcomes among TGA patients with prior atrial switch repair. Our results also underline the need of better risk-stratification for sudden cardiac death in those patients.

15–28 Abstract 19–11

161 AZYGOS VEIN COIL: AN ATRACTIVE ALTERNATIVE

Andrew Behunin¹, Michael Giudici¹, Prashant Bhave¹, Alexander Mazur¹, Dwayne Campbell¹

¹ University of Iowa Hospitals and Clinics, Iowa City, IA, USA

Introduction: In spite of improvements in implantable cardioverter-defibrillators (ICD) such as biphasic waveforms and increased delivered shock outputs, some patients, often those with high BMI and/or dilated cardiomyopathies, will still have inadequate defibrillation with a standard lead-to-can vector. In these patients, a subcutaneous array (SQA) may be required which adds substantial morbidity to the implant procedure. The azygos vein (AV) courses behind the left ventricle and may provide an improved shock vector with lower defibrillation thresholds (DFT) and avoid the procedural risks and morbidity of a SQA. Methods: Four male patients with failed defibrillation for ventricular tachycardia or ventricular fibrillation (VT/VF) underwent AV coil placement without procedural complications. In two patients, the elevated DFT was detected at initial implant, whereas the remaining two patients were shocked three and seven times, respectively, for clinical VT/VF before the arrhythmia terminated.

Age	BMI	Heart disease	EF (%)	LVEDD (cm)	DFT before	DFT after
40	42.8	ICM	30	7.7	Fail 40 J	41 J
29	53.1	NICM	35	6.7	Fail 30 J	28 J
52	44.3	NICM	30	6.7	3 shocks of 35 J	20 J
62	29.9	NICM	20	6.4	7 shocks of 41 J	21 J

Results: In all cases, placement of the AV coil resulted in a successful decrease in the defibrillation threshold. In one case, the defibrillation threshold remained at maximum output of his device; however, previous DFT testing on two separate occasions were unsuccessful at aborting induced VT/VF and external rescue was required. Conclusion: Azygos vein coils offer an attractive alternative for patients with high defibrillation thresholds. The AV runs posterior to the heart allowing for a true anterior-posterior defibrillation vector. This coil can be placed at the time of initial implant without significant additional procedure time or patient morbidity. While subcutaneous arrays are also efficacious, they may expose the patient to additional risk of bleeding, infection, pneumothorax, extra scars, and post-procedural pain.

15–29 Abstract 19–13

162 REDUCTION OF INAPPROPRIATE SHOCK THERAPY IN S-ICD PATIENTS THROUGH INTRAOPERATIVE SELECTION OF IMPLANTATION SITE ACCORDING TO NEUROANATOMICAL CRITERIA OF SENSORY NERVE SUPPLY IN ADJACENT THORACIC MUSCLE

Ulrich Backenkoehler¹

¹ Praxis für Kardiologie, Hamburg, Germany

Background: Implantation of subcutaneous ICD (S-ICD) has become a routine intervention in patients in whom out of distinct reasons the deployment of a conventional intracardiac lead system is impossible or contraindicated. However, the implantation of the S-ICD-can and the subcutaneous lead with a wide field of detection may typically lead to inappropriate myopotential detection and S-ICD-therapy as caused by ICD-movement or externally applied mechanical muscle irritation. Myopotentials are mediated by proprioceptive sensory nerve receptors (SNR). Therefore, we searched for number, location and structure of SNR in the adjacent thoracic tissue of the anterior serratus muscle (ASM) in order to identify optimal implantation sites allowing for improvement of postoperative results. Methods: Topography and ultrastructure of SNR in the anterior serratus muscle were analyzed in 12 models of adult female NMRI-mice. Three SNR-types were identified using light and electron microscopy: muscle spindles (MSP), lamellated Pacini corpucles (PC) and Golgi tendon organs (GTO). Their location within the skeletal muscle was determined by 3D-image processing of three complete thorax section series. Results: Within the relevant structure of the anterior serratus muscle (ASM), a total amount of n = 27 ± 5 MSP were found per thorax. The vast majority of SNR of the MSP-type were identified either within the area of tendinous origin (n = 11 ± 4) or the fibromuscular tissue of muscle insertion (n = 13 ± 4), respectively; in all samples, only a very small number of MSP were located within the central portions of the ASM (n = 3 ± 1). GTO (n = 3 ± 1) and rare PC were exclusively found within the fibrous tissue of the tendinous muscle insertions Conclusion: To avoid SNR irritation near the tendinous zones of origin and insertion of the ASM that are richly supplied with a large number of MSP as well as GTO and PC, special attention should be paid to the implantation of the S-ICD-can within the anterolateral central muscle region close to the landmark of the anterior axillary line. Thus, the risk of electrical noise and thoracic myopotential interference resulting in inappropriate S-ICD therapy may be reduced by a neuroanatomically guided implantation site

15–30 Abstract 19–15

163 IMPLANTABLE CARDIOVERTER DEFIBRILLATOR IN PRIMARY PREVENTION FOR CHRONIC HEART FAILURE: INCIDENCE AND PREDICTORS OF APPROPRIATE THERAPY.

Arsène Monnier¹, François Lesaffre¹, Jean Pierre Chabert¹, Pierre Nazeyrollas¹, Damien Metz¹

¹ Service de Cardiologie CHU de Reims, Reims, France

Background: implantable cardioverter defibrillator (ICD) has been shown to be associated with a significant reduction in the risk of sudden cardiac death. Despite this benefit, considering the morbidity related to implantation and the financial impact on the health care system, it may be helpful to distinguish patients who would most benefit from primary ICD treatment and thus improve patient selection. The aim of this study was to assess the prevalence and to identify the clinical predictors of appropriate ICD therapy in patients with chronic heart failure following implantation of an ICD for primary prevention. Methods: A monocenter retrospective analysis was performed and all consecutive patients undergoing implantation of ICD for primary prevention were included. Baseline patient demographic and medical data was collected from our institutional database. Device interrogations during visits were performed and appropriate therapies, either ATP or shock, were recorded. The endpoint follow-up was the last available device interrogation in our center. Results: Of 317 primary prevention patients undergoing ICD implantation, 203 (64 %) had ischemic cardiomyopathy (ICM) and 114 had non-ischemic dilated cardiomyopathy (NIDCM). After a mean follow-up time 760 ± 599 days, 56 (17.7 %) had received appropriate ICD therapies. Mean LVEF was 26 ± 6 %. By univariate comparison, left ventricular diastolic diameter (LVDD) ≥ 65 mm (p = 0.035) and lack of diuretic (p = 0.024) were predictors for ICD therapy. Absence of cardiac resynchronization therapy device (CRTD) was close to be significant (p = 0.055). ICM and NIDCM patients benefit from ICD implantation did not differ (p = 0.941). By multivariate analysis, elderly patients ≥ 65 years (HR 1.92 CI 95 % 1.06–3.51, p = 0.032), LVDD ≥ 65 mm (HR 2.01, CI 95 % 1.11–3.65, p = 0,022) and lack of diuretic (HR 0.31, CI 95 % 0.16–0.61, p < 0.001) were all significant independent predictors for ICD therapy. Overall, the absence of CRTD device was close to be significant (HR 0.53, CI 95 % 0.28–1.03, p = 0.062), but was significant in NIDCM population (p = 0.007). During follow-up, the onset of atrial fibrillation (p = 0.027) and hospitalization for acute heart failure (p = 0.002) were significantly associated with ICD-delivered therapy. Conclusions: ICD therapy occurred in 17.7 % of primary prevention patients without any difference between ischemic and non-ischemic dilated cardiomyopathy. Older age, left ventricular dilatation and absence of diuretic were predictive factors for ICD therapy and presence of CRTD was close to be significant.

Poster session D part 1:

Monday, April 20, 2015

Posters exposed from 2:00 PM to 5:00 PM

Presenters and chairpersons present from 02:00 PM to 3:30 PM

Pacing and related complications

16–1 Abstract 22–10

164 LIMITED VASCULAR ACCESS AND CARDIAC PACEMAKER IMPLANTATION – A NEW APPROACH

Niall Campbell¹, Ross Hunter¹, Richard Schilling¹

¹ Queen Mary, University of London, London, UK

INTRODUCTION: Patients with long venous lines frequently have occlusion of veins in the upper mediastinum. This is the first description of leadless pacing technology utilized in a patient with limited vascular access and at risk of recurrent device infection. CASE: A sixty-six-year-old man had recurrent unexplained episodes of sepsis over 8 months, which clinically responded to broad spectrum antibiotics. He had a history of end-stage renal disease secondary to diabetes mellitus, requiring hemodialysis and a dual chamber pacemaker implanted in 2004 for complete AV block. Blood cultures grew Staphylococcus aureus. Transoesophageal echocardiography showed vegetations on his RV lead. LV systolic function was good. All leads and generator were then extracted; the leads were removed percutaneously using mechanical sheaths, although the distal tip of the RA lead remained in situ. He received intravenous antibiotics for 3 weeks until infection had clinically and biochemically resolved. Selective contract injection via subclavian vein showed venous occlusion at SVC to RA junction. Decision was made to implant a leadless pacemaker (Nanostim, St Jude Medical). Delivery system was administered via the right femoral vein (Figure: marked ‘a’) and device was placed at the RV apex (‘b’). Procedure and screening times were 24.0 and 3.8 min respectively, with no complications. Device parameters at 1 year follow-up were stable with no evidence of infection recurrence. DISCUSSION: Options for permanent cardiac pacemaker implantation are limited in patients with occlusion of the superior mediastinal veins. In patients with limited access via the superior approach, leadless pacemaker technology provides a novel, alternative novel approach. This has the potential to be the first line-approach for patients on hemodialysis requiring pacing.

16–2 Abstract 23–12

165 THE PROBABILITY OF FORMATION OF VEGETATIONS IN PATIENTS WITH LEAD DEPENDENT INFECTIVE ENDOCARDITIS

Anna Polewczyk¹, Wojciech Jacheć², Andrzej Tomaszewski³, Wojciech Brzozowski³, Maranna Janion¹, Andrzej Kutarski³

¹ Swietokrzyskie Cardiology Center, II Department of Cardiology,The Jan Kochanowski University, Department of Health Sciences, Kielce, Poland; ² Silesian Medical University, II Cardiology Department, Zabrze, Poland; ³ Medical University, Department of Cardiology, Lublin, Poland

Background. Lead dependent infective endocarditis (LDIE) is a serious disease with very often incidence of right heart vegetations (RHV). Factors affecting vegetations development are relatively little known. Methods. Multivariable analysis of factors potentially related to risk of vegetations development in group 414 patients with LDIE (280 with confirmed RHV presence) was conducted. This group was separated from 1426 consecutive subjects underwent transvenous lead extraction (TLE) procedures in years 2006–2013 in the TLE single Reference Center. Results. The results were demonstrated in the figure (Fig 1). Multivariable Cox analysis effect of test parameters on the probability of the formation of vegetations in LDIE patients Conclusions: ICD leads presence was a key positive factors in formation of RHV (HR 2746; 95 %CI (1914–3938)). Other prognostic factors were amount of leads (increased risk by 22 %) and previous pocket interventions (increased risk by 21.5 %). Bigger left ventricle ejection fraction was considered with lower probability of vegetation presence It is problematic why the previously procedures of pacemaker implantations were also a protective factor (decreased risk by 53.5 %). Both previously antibiotic and antiplatelet therapy had statistically borderline impact

16–3 Abstract 23–17

166 IS TRANSVENOUS LEADS EXTRACTION MORE RISKY IN PATIENTS WITH VEGETATIONS?

Anna Polewczyk¹, Andrzej Tomaszewski², Wojciech Brzozowski², Marianna Janion¹, Andrzej Kutarski²

¹ Swietokrzyskie Cardiology Center, II Department of Cardiology; The Jan Kochanowski University, Department of Health Sciences, Kielce, Poland; ² Medical University, Department of Cardiology, Lublin, Poland

Background. Transvenous lead extraction (TLE) is the key procedure in management of lead-dependent infective endocarditis (LDIE). Right heart vegetations (RHV) are probably a risk factor of procedural complications. The aim of this study is assessment of efficacy and safety of TLE in patients with the RHV. Methods. The comparative retrospective analysis of efficacy and safety of TLE procedures in 280 patients with right heart vegetations and 134 subjects without RHV was conducted. Patients were underwent TLE due to LDIE in years 2006–2013 in single Reference Center. Results are demonstrate in the table and figures

Patients/procedures	LDIE patients with RHV	LDIE patients without RHV	P
Number	280 (67.6 %)	134 (32.4 %)	–
Age of pts (years)	65.5 ± 14.4	67.5 ± 14.8	0.2
Sex, male (%)	186 (66.4 %)	98 (73.1 %)	0.17
Number of leads extracted (mean) (SD)	2.12 ± 0.93	2.07 ± 0.90	0.61
ICD lead	65 (23.21 %)	22 (16.4 %)	0.11
CS lead	58 (20.71 %)	22 (16.42 %)	0.30
Lead dwell time—in months (mean) (SD)	84.65 ± 61.33	77.24 ± 58.74	0.24
Unecessary loops of the leads (%)	25 (8.93 %)	10 (7.46 %)	0.61
Number of procedures before extraction (mean) (SD)	2.25 ± 1.43	2.27 ± 1.21	0.89
Procedure time—in minutes (mean) (SD)	111.43 ± 48.68	110.07 ± 61.21	0.80

Conclusions: Both groups of patients with LDIE were comparable in terms of procedural risk factors. TLE in patients with LDIE was safety and efficacy, but presence of vegetations increased the risk of procedure. Nevertheless, clinical success and frequency of major and minor complications were also comparable.

16–4 Abstract 23–20

167 DRY PERFORATION—FREQUENT MECHANISM OF ICD LEAD DYSFUNCTION

Andrzej Kutarski¹, Andrzej Tomaszewski¹, Wojciech Brzozowski¹, Krzysztof Oleszczak¹

¹ Dept. of Cardiology, Medical University, Lublin, Poland

Theoretically increased risk of perforating lead extraction inclined us for attempt to localize tip of lead in relation to epicardium and the commonness of the observed phenomenon was surprising. Methods: TEE and TTE and other preoperative findings from computer clinical data of patients underwent transvenous leads extraction (TLE) in single reference center were analyzed. Results: We have extracted 2574 ingrown leads from 1536 patients; in 390 ICD leads were extracted due to infection (39.4 %) or different form of lead dysfunction (63,6 %). In 86 patients (22 %), we diagnosed different forms of perforation of right ventricle wall with ICD lead. ECHO: dry perforation (tip in epicardial space, no fluid) 64 (74 %), small “lens” of dense fluid round the lead tip 6 (7 %), wet perforation (thin layer of fluid 5 (6 %), deep subepicardial tip penetration 4 (5 %) but in 3 (%) of patients diagnosis was based on other symptoms (P/S/I abnormalities). Indications for TLE: “lead dysfunction” 54 (62 %), diagnosed perforation 13 (15 %) and infection 13 (15 %). In 18 patients, all parameters of pacing/sensing/impedance were normal (21 %) but in other drop of sensing 41 (47 %) or sizzles 15 (18 %) were noted, rise of Pth or loss of pacing in 41 (47 %) were observed as rise or drop in 3 of impedance in 42 (52 %) were noted in different combinations. Atypical chest pain was presented by 6 patients (7 %). Perforating lead location: RVA 80 (93 %), “RVOT” 7 %. Lead’s model: active fixation 45 (52 %), passive −41 (48 %). Time implantation—diagnosis: aver. 51.0 (1–146) months; 5 years 35. Fifty-nine of 86 (69 %) perforations were diagnosed >3 years after implantation. Dry perforation was rarely visible in standard chest X-ray, standard ECHO showed very low sensitivity; the tip of lead must to be search using additional projections. Conclusion: 1. “Dry” perforation (without cardiac tamponade or marked volume of fluid in pericardial space) consists relatively frequent finding in ICD pts referred fort TLE (86/390, 22 %). It demonstrates usually as “lead dysfunction” mask but in remaining pts is asymptomatic. 2. Exact ECHO examination using additional projections and careful evaluation of evolution of P/S/I conditions permit to put more accurate diagnosis 3. Dry perforation consist late complication of ICD therapy and manner of lead implantation seems to play important role.

16–5 Abstract 23–13

168 LONG-TERM FOLLOW RELIABILITY OF SWEET-TIP TYPE SCREW-IN LEADS IN A SINGLE JAPANESE HEART CENTER

Hidemori Hayashi¹, Richard Schlling¹, Asuka Takano², Gaku Sekita², Hiroyuki Daida², Yuji Nakazato³

¹ St Bartholomew’s Hospital, London, UK; ² Juntendo University Hospital, Tokyo, Japan; ³ Juntendo Urayasu Hospital, Chiba, Japan

Introduction: According to recent increase of patients with cardiac implantable devices, the implanting number of pacing leads has also been increased. Although active-fixation leads made stable atrial and ventricular pacing feasible, the pacing lead longevity is affected by various factors such as insulation materials, lead structures and the methods of venous approach. The purpose of this study is to investigate long-term reliability of active-fixation leads and stability of electrical characteristics. Methods and results: A total of 1196 pacing leads were implanted in 830 patients consecutively from 2006 to 2013 in a single implanting center in Japan. In this retrospectively study, we could trace 1092 leads in 750 patients for investigating the prognosis of implanted leads. The measurements value of pacing thresholds, sensing amplitudes of the atrial or ventricular activities, and lead impedances were obtained from the medical records at the time of implantation and during follow-up at the device clinic. All pacing leads were FINELINE II Sterox EZ Leads (Boston Scientific, MN, USA) except for shock lead in ICD patients. The mean follow-up period was 51.3 ± 29.2 month (median 48 month). Six hundred eighty-two leads were implanted in the atrium, and 410 leads in the ventricle. The cephalic vein cut down access was 914 leads and subclavian puncture approach was 178 leads. The overall survival rate was 99.6 % at 5 years, and 99.6 % at 10 years. The electrical characteristics of both atrial and ventricular leads have slightly changed after implantation but all of them remained stable during follow-up period. Verified complete lead fractures were observed in 3 out of 1092 leads (0.27 %), and incomplete fracture in 1 lead (0.09 %) all of which were implanted by the subclavian puncture method. The device-related infection was observed in 4 patients (0.37 %) but all devices and leads were extracted and then re-implanted safely. Conclusion: The overall reliability of Sweet-tip type screw-in leads is satisfactory and electrical characteristics also clinically acceptable through long-term follow up period. The cut-down access from cephalic vein should be recommended as the first-line approach if considering the long-term durability of pacing leads.

16–6 Abstract 23–11

169 THE INFLUENCE OF VEGETATIONS ON CLINICAL PRESENTATION OF LEAD DEPENDENT INFECTIVE ENDOCARDITIS

Anna Polewczyk¹, Andrzej Tomaszewski², Wojxiech Brzozowski², Marianna Janion¹, Andrzej Kutarski²

¹ Swietokrzyskie Cardiology Center II Department of Cardiology The Jan Kochanowski University, Department of Health Sciences, Kielce, Poland; ² Medical University, Department of Cardiology, Lublin, Poland

Background. Right heart vegetations (RHV) are the serious signs of lead dependent infective endocarditis (LDIE) and one of the big diagnostic criteria of LDIE. Clinical presentation of LDIE is very differentiated and RHV probably influence the some symptoms and laboratory or echocardiographic parameters. Methods. The comparative analysis of clinical presentation of 280 patients with RHV with 134 subjects without confirmed vegetations presence was conducted. These groups were underwent transvenous leads extraction (TLE) procedure due to LDIE in single Reference Center in years 2006-2013. Results. The results were demonstrated in the table.

Patients / clinical presentations		LDIE with RHV	LDIE without RHV	p
		n = 280	n = 134
Clinical symptoms	Fever, chills (%)	66.1	34.4	0.0001
	Pocket infection (%)	58.7	85.6	0.0001
	Pulmonary infections (%)	28.3	17.8	0.02
	Positive blood cultures (%)	66.1	75.3	0.06
Laboratory parameters	Leucocytes WBC (/μl) (mean ± SD)	9918 ± 4852	9050 ± 5818	0.12
	ESR (mm after1 h) (mean ± SD)	44.3 ± 30.2	39.6 ± 28.5	0.41
	CRP (mg/dl) (mean ± SD)	52.5 ± 66.2	35.0 ± 52.8	0.01
	Proalcitonin (pg/ml) (mean ± SD)	1.9 ± 4.8	0.2 ± 0.2	0.09
Echocardio-graphy findings	LVEF (%) (mean ± SD)	49.4 ± 14.4	52.5 ± 13.5	0.05
	LVDD (mm) (mean ± SD)	53.7 ± 10.5	54.4 ± 9.4	0.55
	PASP (mmHg) (mean ± SD)	34.7 ± 17.1	29.7 ± 17.0	0.06

Conclusions: RHV presence is connected with more acute clinical manifestations of LDIE: fever, chills and pulmonary infections are significantly more frequent in these patients. Conversely, the pocket infections (PI) are less often in LDIE with RHV—probably patients with PI are earlier treated. From inflammatory parameters, only high CRP level is specific for RHV occurrence. Patients with RHV have also more often systolic dysfunction of left ventricle..

16–7 Abstract 23–10

170 UNDECIDED ABOUT GETTING A PACEMAKER? TAKE ONE FOR A TEST-DRIVE

Michael Giudici¹

¹ University of Iowa Hospitals, Iowa City, IA, USA

Background: Bradycardia due to sinus node disease or slow conduction of atrial fibrillation may be a slowly progressive problem that occurs over years. Some patients, and implanters, are ambivalent about proceeding with pacemaker implantation where there may not be clear evidence of benefit. We offer these patients a 2-week test-drive to allow them to assess the potential benefit of a permanent pacemaker implantation. Methods: Over a 42-month period, five patients (3 F/2 M, aged 40–82 years) with sinus bradycardia-4 and slow conduction of atrial fibrillation-1 underwent percutaneous placement of a permanent pacing lead via a subclavian approach in either the right atrium-4 or right ventricular septum-1. The lead was then attached to a non-sterile permanent pacemaker which was sewn to the skin and an occlusive dressing was applied. The device was then programmed to a rate-responsive mode at appropriate heart rates for each patient. After 2 weeks, the devices were removed. Results: All five patients subsequently chose to undergo permanent pacemaker placement. There were no complications associated with the initial implantation procedure, the 2-week trial period, or device removal. Conclusions: In bradycardic patients who are undecided about pacemaker implantation, a 2-week test-drive with percutaneously placed temporary permanent pacemaker allows the patient to experience the clinical impact of pacing therapy and may aid in their decision to proceed with the permanent implant.

16–8 Abstract 23–24

171 POLYPROPYLENE BYRD DILATOR SHEATH FRACTURE—MAY LEAD TO SERIOUS PROBLEMS IF NOT IDENTIFIED ON TIME.

Andrzej Kutarski¹, Maciej Polewczyk², Aneta Polewczyk², Anna Polewczyk³

¹ Dept of Cardiology Medical University, Lublin, Poland; ² District Hospital, Kielce, Poland; ³ II Dept. of Cardiology Swiektokrzyskie Cardiology Center; Dept. of Health Scientes The Jan Kochanowski University, Kielce, Poland

Byrd dilator sheath fracture (BDF) during transvenous lead extraction (TLE)—is not a complication if recognized by the operator immediately and eliminated by replacing a damaged sheath with a new one. Objective: The evaluation of BDF prevalence, circumstances and its impact on TLE efficacy. Methods: The retrospective analysis of 1728 TLE procedures (2901 extracted leads) in Reference Centre in Lublin. Results: Fracture or even rupture of mechanical sheath occurred relatively rarely (2.25 % procedures, 1.34 % extracted leads). BDF was identified in: superior vena cava (45 %), right atrium (20 %), right brachiocephalic vein (20 %), left subclavian vein (13 %) and right ventricle (3 %). Green sheaths (10 F) used in pacemaker leads extraction were most often damaged (51 %), white (11.5 F) frequently needed for ICD leads removal were second (31 %), orange (13 F) used as an option if procedural difficulties arose, were broken rarely (15 %). In 20 % of procedures fracture of another sheath occurred in the same location. Eighty percent of damages were eliminated by covering the broken inner sheath with outer sheath and their removal. In 10 % cases, wider dilator was introduced over the damaged one and extracted at the end of the procedure with the lead. BDF was observed more frequently in younger patients, in those with more implanted leads, with longer lead body dwelling time, with unnecessary lead loops and with leads on both sides of the chest. Fractures may be connected with the phenomenon of lead-to-lead adherence and TLE from right subclavian approach. Although BDF concerned more difficult procedures, complications rate in these cases was not significantly higher. Full radiological success rate was slightly lower probably because the leads were strongly ingrown in vessel walls. Conclusion: Byrd dilator fracture phenomenon should be well known to the operator. To prevent serious consequences, a whole sheath ought to be observed all the time during procedure. Keywords: lead extraction, lead extraction technical problems, Byrd dilator fracture, sheath fracture, extracting damaged sheath, complications of lead extraction

16–9 Abstract 31–13

172 TIME COURSE AND CHARACTERISTICS OF TACHYARRHYTHMIAS AFTER IMPLANTATION OF THE HEARTMATE II

Ameeta Yaksh¹, Charles Kik¹, Paul Knops¹, Korinne Zwiers¹, Maarten J.B. Van Ettinger¹, Marcel C.J. De Wijs¹, Peter Van de Kemp², Olivier C. Manintveld¹, Alina A. Constantinescu¹, Ad J.J.C. Bogers¹, Natasja N.M. De Groot¹

¹ Erasmus MC, Rotterdam, Netherlands; Sorin, Rotterdam, Netherlands

Background: Ventricular tachyarrhythmias (VTA) have been frequently reported after implantation of left ventricular assist devices but there is no information on supraventricular tachycardias. The goal of this study was to examine not only the frequency and characteristics of ventricular tachycardias (VT) after implantation of the Heartmate II but also (supra) ventricular ectopic beats ((S)VEB) and atrial flutter (AFL)/fibrillation (AF). Methods: Continuous rhythm registrations were obtained from 8 patients (7 male; 43 ± 12 years) during the first 5 days after Heartmate II implantation. Hospital records were analysed to examine late postoperative tachyarrhythmias. Hemodynamic parameters (mean arterial pressure (MAP), right atrial pressure (RAP), heart rate (HR) and ST-deviation (d-ST)) prior to VT episodes were compared with sinus/pacing rhythms (reference periods). Results: VT (N = 6), AF (N = 3) and AFL (N = 1) were pre-operatively present in 6 patients. VEBs were postoperatively observed in all patients. Frequent single VEBs (>10/H,N = 90.111), ventricular-couplets, runs, single SVEBs, SV-couplets, runs occurred in, respectively, 42.2, 34, 20, 3.9, 2.6 and 1.4 % of the recording time. Prior to VT episodes (N = 121), MAP decreased, HR, d-ST increased and RAP remained unaltered. Postoperatively, 5 patients developed either VT (N = 2), AF (N = 1) or both VT/AF (N = 2) during a follow-up of 18 ± 14 months. PoVT were mainly preceded with sinus rhythm (46 %) or short-long-short-sequence (43 %) and initiated by V-run (43 %). Conclusion: Both atrial and ventricular tachyarrhythmias are frequently observed in patients after Heartmate II implantation despite improvement in cardiac hemodynamics caused by cardiac unloading.

16–10 Abstract 23–16

173 TRANSVENOUS LEADS EXTRACTION IN DIABETIC PATIENTS- SAFETY AND EFFECTIVENESSESS, SINGLE CENTER ANALYSIS AMONG 1715 PROCEDURES

Anna Polewczyk¹, Andrzej Tomaszewski², Wojciech Brzozowski², Marianna Janion¹, Andrzej Kutarski²

¹ Swietokrzyskie Cardiology Center, II Department of Cardiology; The Jan Kochanowski University, Department of Health Sciences, Kielce, Poland; ² Medical University, Department of Cardiology, Lublin, Poland

Background. The relationship between diabetes mellitus and risk of transvenous leads extraction (TLE) procedure has not been investigated thoroughly. Methods. Analysis of clinical data two groups of patients: 323 diabetic and 1392 non-diabetic underwent TLE in single Reference Center in years 2006–2013 was conducted. Clinical and procedural risk factors were assessed with comparison of safety and efficacy of TLE in these patients. Results. The results are demonstrated in the table

Patient/system/procedure information	Diabetes	No diabetes	P
Number of patients	323	1392	–
Patient’s age (SD)	69.00 ± 10.28	63.70 ± 16.85	<0.0001
Sex (female)	11,134.37 %	56640.66 %	0.04
Infective indications (LDIE)	6319.50 %	21,715.59 %	0.09
Vegetations	7924.46 %	26,819.25 %	0.04
Infective indications (pocket infection)	8526.32 %	32,323.20 %	0.23
Infective indications (total)	14,845.82 %	54,038.79 %	0.03
Non-infective indications	17,554.18 %	85,261.21 %	0.03
Prior sternotomy	4915.17 %	20,214.51 %	0.75
Renal failure (crea >2.0) or hemodialysis	154.64 %	332.37 %	0.03
BMI	29.4 ± 5.0	26.9 ± 8.0	<0.0001
Number of leads in heart before lead extraction (SD)	1.93 ± 0.76	1.99 ± 0.80	0.22
Number of extracted leads in one patient (SD)	1.64 ± 0.82	1.65 ± 0.79	0.84
Number of leads in the system	1.78 ± 0.67	1.80 ± 0.63	0.61
Number of abandoned leads	0.16 ± 0.50	0.23 ± 0.57	0.04
CS lead extraction	4513.93 %	19,514.01 %	0.97
ICD lead extraction	9629.72 %	846.03 %	<0.0001
Overmuch of lead length in right atrium—too long loops or long loop in tricuspid valve	5115.79 %	34,124.50 %	<0.01
Number of procedures before lead extraction	1.75 ± 1.03	1.92 ± 1.19	0.02
Mean extracted lead body dwelling time (months)	71.8 ± 57.9	84.3 ± 60.6	0.0008
Intracardiac abrasion of the leads	5517.03 %	27,019.40 %	0.31
Operating room stay-in time (whole procedure duration) (minutes)	106.9 ± 39.7	109.2 ± 46.7	0.41
Major complications	20.62 %	221.58 %	0.18
Minor complications	61.86 %	201.44 %	0.58
Technical problems during TLE	4012.38 %	22,616.24 %	0.09
Full radiological success	31,296.59 %	132,094.83 %	0.18
Clinical success	32,099.07 %	136,297.84 %	0.15
Full procedural success	31,296.59	131,994.76 %	0.17
Death during periprocedural period	20.62 %	60.43 %	0.63

Conclusion. Safety and efficacy of TLE procedures were comparable in two groups of patients but—paradoxically—patients with diabetes had less potential procedural risk factors. Especially, the lead dwelling time was significantly longer in non-diabetic population. Additionally, abandoned leads and loops of the leads, often ingrown, were also more often in patients without diabetes mellitus. Probably, these differences balanced the risk of TLE in patients with vegetations—more often in diabetic subjects.

Atrial fibrillation and anticoagulant therapy

16–11 Abstract 15–18

174 A CROSS-SECTIONAL SURVEY ON THE PERCEPTION OF THE ANTICOAGULANT TREATMENT IN ATRIAL FIBRILLATION IN PHYSICIANS FROM COUNTY HOSPITALS

Yihong Sun¹, Changying Wang², Yitong Wang¹, Dayi Hu³, Lina Wang³

¹ Heart Center, Peking University People’s Hosiptal, Beijing, China; ² Department of Cardiology,The First Affiliated Hosiptal of Chongqing Medical University, Chongqing, China; ³ Peking University People’s University, Beijing, China

Objective: Warfarin was underused in Chinese patients with atrial fibrillation (AF) especially in low-level hospitals. The purpose of this survey was to investigate the perceptions of the prevention from stroke by giving warfarin in physicians from county hospitals. Methods: A cross-sectional survey was conducted in a convenience sample of physicians from 9 county hospitals in Jiangsu, Henan, Zhejiang provinces. The questionnaire consisted of questions on physicians’ knowledge, awareness and concerns regarding atrial fibrillation diagnosis, risk score of thrombosis and hemorrhage and warfarin treatment, including the rate of anticoagulation, CHADS2score, CHA2DS2-VASC score, HAS-BLED score and the target of international normalized ratio (INR),etc. Results: From Jun to Nov in 2013, 292 questionnaires were returned from 9 county hospitals. Most of physicians 83.2 % (173) were from tier 1 and 2 hospitals. The median percentage of the anticoagulant treatment self-reported was 30.0 %(10.0 %～60.0 %) in patients with rheumatic valvular AF, 20.0 %(10.0%～50.0 %) in patients with non valvular AF and80.0 %(40.0%～100.0 %) with post mechanical heart valve replacement. The most common concerns of prescribing warfarin were about the bleeding adverse reactions related to warfarin 74.0 % (154), regular assessment of monitor coagulation 65.4 % (136) and advanced age 44.7 %(93). Half 51 % (106) of the physicians will use ECG for the diagnosis of AF and only 28.3 % (59) will use both ECG and Holter. Among the physicians who reported using INR to monitor warfarin, 62.5 % (130) indicated a target range between 2 and 3 and lower target were indicated in one third of the participants. The proportion of the physicians who were aware of CHADS2 score and CHA2DS2-VASC score were 51.0 % (106) and 41.3 %(86), but the correct answer to the risk factors only accounted for 15.4 %(32ï¼ ‰and 6.3 %(13) respectively. Although 34.6 % (72) of the physicians were aware of HAS-BLED score, only 5.3 % (11) correctly selected the 9 parameters. 68.3 % (142) of the physicians indicated the Vitamin K is the antidote for warfarin. Conclusions: This study highlighted physicians’ concerns and deficits in knowledge regarding the risk stratification and anticoagulant treatment in AF patients. Concerns about the risks of bleeding and INR monitoring appeared to be the biggest barriers for anticoagulant. Keywords: Atrial fibrillation, Anticoagulation; Knowledge; Warfarin;

16–12 Abstract 15–17

175 APIXABAN 2.5 MG BID CAN REVERSE LEFT ATRIAL APPENDAGE CLOT.

Magdi Sami¹, Beatriz Vaquerizo¹

¹ McGill University, Montreal, Canada

This is the case presentation of a 63-year-old woman who sustained a massive right hemispheric stroke on Nov 7, 2013. She had presented with persistent atrial fibrillation and mild hypertension in 2008 at age 57 (CHADSVASC score of 2) and was started on warfarin. Later that year, she was fitted with a DDD pacemaker because of severe symptomatic bradycardia induced by beta blockers used for rhythm control. She was paced at 80 BPM and free of atrial fibrillation for at least 6 months prior to her presentation to the emergency (ER) Nov 2, 2013, with acute appendicitis. Her INR was reversed with vitamin K; she underwent appendectomy later that day and was discharged on warfarin, Nov 4, with an INR of 1.4. On Nov 7, she had a massive right hemispheric stroke and was given immediate thrombolysis which resulted in a hemorrhagic transformation of the stroke; warfarin was stopped. Dec 2, she presented again to ER with deep vein thrombosis and was fitted with an inferior vena cava (IVC) filter. For stroke prevention, she was considered for a left atrial occlusive device (LAOD). A transoesophageal echo (TEE), however, revealed two left atrial clots. A CT scan revealed only partial resolution of the right hemispheric hematoma. The patient was started on apixaban 2.5 mg BID. Two months later, there was a complete resolution of all left atrial clots. Her repeat CT scan had also shown continuous resolution of the right hemispheric clot and the dose of apixaban was increased to full dose, 5 mg BID. Nov 2015, the patient has made a substantial recovery of her left hemiplegia is able to talk and walk unaided. She remains in SR on apixaban 5 mg BID, sotalol and anti-hypertensive. Conclusion: Apixaban 2.5 mg can resolve left atrial clots without increasing pre-existing brain hematoma. Vitamin K may result in a pro-thrombotic state, when used to reverse warfarin anticoagulation.

16–13 Abstract 14–14

176 A CROSS-SECTIONAL SURVEY ON THE PERCEPTION OF THE ANTICOAGULANT TREATMENT IN ATRIAL FIBRILLATION IN PHYSICIANS FROM COUNTY HOSPITALS

Yihong Sun¹, Changying Wang², Yitong Wang¹, Dayi Hu¹, Lina Wang¹

¹ Heart Center, Peking University People’s Hosiptal, Beijing, China; ² Department of Cardiology,The First Affiliated Hosiptal of Chongqing Medical University, Chongqing, China

Background: Warfarin was underused in Chinese patients with atrial fibrillation (AF) especially in low-level hospitals. The purpose of this survey was to investigate the perceptions of the prevention from stroke by giving warfarin in physicians from county hospitals. Methods: A cross-sectional survey was conducted in a convenience sample of physicians from 9 county hospitals. The questionnaire consisted of questions on physicians’ knowledge and concerns regarding atrial fibrillation diagnosis and warfarin treatment, including anticoagulation rate, CHADS2score, CHA2DS2-VASC score, HAS-BLED score and the target of international normalized ratio (INR). Results: From Jun to Nov in 2013, 292 questionnaires were returned from 9 county hospitals. The median percentage of the anticoagulant treatment self-reported was 30.0 % (10.0%～60.0 %) in patients with rheumatic valvular AF, 20.0 % (10.0%～50.0 %) with non-valvular AF and80.0 % (40.0%～100.0 %) with post mechanical heart valve replacement. The most common concerns of prescribing warfarin were about the bleeding adverse reactions related to warfarin 74.0 % (154), regular assessment of monitor coagulation 65.4 % (136) and advanced age 44.7 % (93). Half 51 % (106) of the physicians will use ECG for the diagnosis of AF. Among the physicians who reported using INR to monitor warfarin, 62.5 % (130) indicated a target range between 2 and 3. The proportion of the physicians who were aware of CHADS2 score and CHA2DS2-VASC score were 51.0 % (106) and 41.3 % (86), but the correct answer to the risk factors only accounted for 15.4 % (32ï¼ ‰and 6.3 % (13)), respectively. Although 34.6 % (72) of the physicians were aware of HAS-BLED score, only 5.3 % (11) correctly selected the 9 parameters. Of the physicians, 68.3 % (142) indicated the vitamin K is the antidote for warfarin. Conclusions: This study highlighted physicians’ concerns and deficits in knowledge regarding the risk stratification and anticoagulant treatment in AF patients. Concerns about bleeding risks and INR monitoring appeared to be the biggest barriers for anticoagulant.

16–14 Abstract 15–50

177 DIFFERENT ORAL ANTICOAGULANTS IN REAL-LIFE PATIENTS WITH ATRIAL FIBRILLATION : CLINICAL ASPECTS AND PROBLEMS

Olga Litunenko¹, Baiba Lurina¹, Marina Kovalova², Gita Rancane, Iveta Sime⁴, Valters Stirna⁴, Galina Dormidontova⁵, Janis Guslens⁶, Biruta Tilgale⁷, Davis Polins¹, Janis Raibarts, Janis Pudulis⁷, Evija Miglane⁸, Aivars Lejnieks⁷, Oskars Kalejs⁸

¹ Riga Stradins University, Riga, Latvi; ² Jelgava Regional Hospital, Jelgava, Latvia; ³ Ventspils Regional Hospital, Ventspils, Latvia; ⁴ Liepaja Regional Hospital, Liepaja, Latvia; ⁵ Daugavpils Regional Hospital, Daugavpils, Latvia; ⁶ Riga Technical University, Riga, Latvia; ⁷ Riga East University Hospital, Riga, Latvia; ⁸ P. Stradins Clinical University Hospital, Riga, Latvia

Background. Oral anticoagulants (OAC) have been the first-line medication for prevention of thromboembolic events in patients with non-valvular atrial fibrillation (NVAF) for a long time, although the usage of vitamin K antagonists (VKA) causes many problems for patients and physicians. Novel OAC (NOAC) implementation in practice is undergoing slowly. Methods. The study enrolled 3542 patients with NVAF under OAC therapy in Latvian hospitals and praxis. Side effects, drug interactions, and complexity of OAC usage were analysed. Events of bleeding were defined as clinically relevant major bleeding (CRMB) and clinically relevant non-major bleeding (CRNMB) according to international guidelines. The second study group included 245 medical practitioners with clinical experience in care of NVAF patients. Results. There were 2214 (62.5 %) users of VKA and 1328 (37.5 %) users of NOAC. According to CHA2DS2-VASc, in VKA group, scale median was 3.9, in NOAC group—it was 2.8. Significantly higher incidence of side effects was detected among VKA compared to NOAC users. All cases of bleeding were reported as follows: 31 % in VKA vs 3.3 % in NOAC users (p < 0.001); CRMB in VKA group had 52 patients (2.3 %) vs 3 (0.2 %) CRMB were observed in NOAC (702 dabigatran and 626 rivaroxaban). CRNMB in VKA group had 194 patients (8.76 %) vs 21 (1.6 %) in NOAC (p < 0.01). No significant difference between dabigatran 150 mg and Rivaroxaban 20 mg, but only one CRNMB in dabigatran 110 mg. More than 50 % of the VKA users had difficulties to adjust OAC dose and to keep the INR between 2.0 and 3.0 and 31.8 % had problems with INR control. Dabigatran was preferred in electrical cardioversion subgroup 64.7 vs. 35.3 % VKA with significantly lower rates of adverse events (p < 0.001) and bleeding. In physicians’ group, 13.9 % cardiologists, 20.8 % internal specialties, 23.8 % general practitioners, 8.9 % surgeons and others, 32.7 % resident physicians—48.5 % did use NOAC in practice. Not sufficient clinical experience was mentioned as main problems for NOAC. The main problems for VKA are lack of compliance, poor INR control and difficulties in dose adjustment. Conclusions. Clinical usage of OAC for AF patients is more complicated in VKA group due to side effects and complexity of use. NOAC are more safety and have significantly less complications and bleeding rate. In electrical cardioversion group, NOAC are preferable for use before and after procedure. Physicians find the usage of NOAC less problematic and they would be ready to use NOAC in practice more often.

16–15 Abstract 01–18

178 ASSESSMENT OF THE SPATIO-TEMPORAL STABILITY OF VOLTAGE DURING ATRIAL FIBRILLATION: QUANTIFYING THE TIME COUSE OF MEAN PEAK-TO-PEAK AF VOLTAGE ALLOWS FOR MEANINGFUL SPATIAL DIFFERENTIATION FOR THE PERSISTENT AF SUBSTRATE

Norman Qureshi¹, Matt Shun-Shin¹, Steve Kim², Chris Cantwell¹, Rheeda Ali¹, Caroline Roney¹, Fu Siong Ng¹, Arunashis Sau¹, Sajad Hayat¹, Michael Kao-Wing¹, Elaine Lim¹, Ian Wright¹, Nick Linton¹, David Lefroy¹, Zachary Whinnett¹, D Wyn Davies¹, Prapa Kanagaratnam¹, Nicholas Peters¹, Phang Boon Lim¹

¹ Imperial College, London, UK; ² St Jude Medical, St Paul, MN, USA

Background. Voltage mapping in atrial fibrillation (AF) has been largely ignored due to its spatiotemporal variability and limitations of current 3D mapping systems. Although varying with time, AF voltage may inform us of the underlying AF substrate. We sought to systematically characterize voltages in AF over varying sampling windows in patients with persistent AF (PsAF). Methods. Patients undergoing PsAF ablation underwent sequential voltage mapping of the entire left atrium (LA) using a 20-pole spiral catheter. The mapping catheter was held stable at each LA site for at least 8 s. Data acquired was exported into a custom-written software for analysis of the mean AF peak-to-peak voltage (AF-V) over multiple sampling windows. Results. We analyzed 51,706 AF cycles (AFCY) from 1113 electrode positions from 8 patients [62 ± 11 years, LA 41 ± 6 mm, CHADSVASC 1.8 (0–3)]. The cycle-to-cycle AF-V variability of a single AFCY was large, with a coefficient of variation (CoV) of 62 %. Increasing the number of AFCY sampled improved the CoV (2 AFCY 40 %, 40 AFCY 8 %). Figure 1 shows the crossover of mean AF-V between the top and bottom quartiles of 172 electrograms sampled over approximately 50 AFCY in a single patient. Across 8 patients, this trend was consistent, with clear separation of the bottom and top AF-V quartiles when sampling was above 10–15 AFCY. In addition, the mean AF-V tends to “settle” to a stable baseline over a similar sampling window. Conclusion. Peak-to-peak voltage in AF is highly variable but increasing its sampling window allows for meaningful spatial differentiation. Further interrogation of these distinct sites may yield crucial insights into the underlying mechanisms of AF maintenance.

Arrhythmias in childhood

16–16 Abstract 01–22

179 ENDOGENOUS INTOXICATION IN CHILDREN WITH HEART RHYTHM DISTURBANCES AND DISELEMENTOSIS

Ann Dubova¹

¹ Donetsk national medical university named after M. Gorky, Donetsk, Ukraine

The study purpose is the assessment of endogenous intoxication rates in children with heart rhythm disturbance having diselementosis. The main group included 59 children (36 girls and 23 boys) in the age from 6 to 18 years old with different heart rhythm disturbances. The control group consisted of 35 health children of the same age (18 girls and 17 boys). Functional state of cardiovascular system was assessed by the standard ECG data, 24-h monitoring by Holter ECG. The biochemical markers of endogenous intoxication were as follows: the concentration of malonic dialdehyde in blood plasma, reduced glutathione (GSH) in red blood cells, lactate dehydrogenase activity in red blood cells. The content of 17 chemical elements (9 toxic and 8 potentially toxic) in children bodies was determined by its level in hair with the help of atomic absorption spectrometry and atomic emission spectrometry. The statistic processing of study results was made by the variational statistics and alternative statistics methods by rate calculation of Spearman rank correlation. In 44 (74.6 %) patients with arrhythmia was documented the exceeding of acceptable concentration of the following toxic chemical elements: barium, cadmium, lead, quicksilver, strontium, aluminium, bismuth (in healthy, ones it was 17.1 %, р < 0.01). In 29 (49.2 %) patients was stated an excess of potentially toxic microelements: strontium, nickel, lithium, arsenic. In all the patients with clinical signs of endotoxicosis was fixed a raised lactate level that was reliably more frequent in comparison with the health controls (11.4 %, р < 0.001). At the same time, the lactate dehydrogenase activity decrease was notable in 36 (61.0 %) persons with arrhythmia (in healthy controls, it was 31.4 %). It is important to notice that in 48 (81.4 %) patients with arrhythmia, the GSН level was decreased whereas in the healthy control group, this decrease had only 8 (25.7 %) persons (р < 0.05). Increase grade of lactate in patients with arrhythmia highly correlated with the severity of clinical signs of endogenous intoxication (r = 0.88), the concentration of toxic chemical elements (r = 0.86), life-threatening nature of the arrhythmia (r = 0.84). All the patients with arrhythmia and diselementosis the clinical manifestations of chronic endogenous intoxication, confirmed by laboratory studies, are identified that reliably distinguished from the health control rates. The lactate increase grade in patients with arrhythmia was highly correlated with the severity of clinical signs of endogenous intoxication, the concentration of toxic chemical elements, life-threatening nature of the arrhythmia.

Poster session D part 2:

Monday, April 20, 2015

Posters exposed from 2:00 PM to 5:00 PM

Presenters and chairpersons present from 03:30 PM to 05:00 PM

Syncope

16–17 Abstract 10–15

180 CARDIONEUROBLATION IN THE RIGHT ATRIUM AS THERAPY FOR CARDIOINHIBITORY NEUROCARDIOGENIC SYNCOPE

Marco Rebecchi¹, Luigi Sciarra¹, Ermenegildo De Ruvo¹, Alessio Borrelli¹, Antonella Sette¹, Antonio Scarà¹, Domenico Grieco¹, Marianna Sgueglia¹, Alessandro Politano¹, Annamaria Martino¹, Giacomo Strano², Stefano Strano², Leonardo Calò¹

¹ Policlinico Casilino, ASL RMB, Rome, Italy; ² Università of Rome “La Sapienza”, Rome, Italy

Introduction. Clinical management of cardio-inhibitory neurocardiogenic syncope (CNS) is often considered difficult especially in young patients with frequent refractory episodes also considering the problematic choice regarding an eventual pacemaker (PMK) implant. Background. Considering that a significant number of ganglionated plexi (GP) are placed in the right atrium (RA), we hypothesized that transcatheter radiofrequency ablation of these selected areas could be an effective treatment to abolish or to reduce CNS episodes. Methods. Seven patients (mean age 47 ± 7 years) affected by frequent typical CNS episodes associated a physical trauma and with a positive response during HU tilt test (T) underwent to RA vagal denervation. An extensive ablation approach at anatomical site of GP (previously described in anatomical study) was performed until atrial electrical activity was completely eliminated (<0.1 mV) and/or vagal reflexes disappeared. Heart rate variability (HRV) and HUT evaluation was assessed at baseline, at 1 day after ablation and at 1,3, 6 and 12 months follow-up. Results. Six patients were free from new syncopal episodes (and cardioinhibitory response at HUT) at a mean FU of 13.2 ± 4.4 months. The patient with early vagal tone restoration suffering from 3 episodes of nausea and dizziness, not followed by the loss of consciousness for effective counter-pressure maneuvers. Conclusions. Cardioneuroablation in RA could be considered an alternative and safe strategy to reduce CNS episodes especially in young patients avoiding or delaying as much as possible PMK implant. A study including a greater number of patients and long term FU is necessary to understand the real efficacy of this procedure.

16–18 Abstract 10–10

181 THE IMPACT OF GENDER ON THE FREQUENCY OF SYNCOPE PROVOKING FACTORS AND PRODROMAL SIGNS IN PATIENTS WITH VASOVAGAL SYNCOPE

Piotr J. Stryjewski¹; Agnieszka Kuczaj²; Jadwiga Nessler³; Bohdan Nessler³; Ryszard Braczkowski⁴; Ewa Nowalany-Kozielska²

¹ Cardiology Department, Chrzanow City Hospital, Poland

² 2nd Department of Cardiology, Zabrze, Medical University of Silesia, Katowice, Poland

³ Coronary Disease Department, Institute of Cardiology, Medical School of Jagiellonian University, John Paul II Hospital, Cracow, Poland

⁴ Department of Public Health, Medical University of Silesia, Katowice, Poland

Background: The aim of the study was a comparative analysis of syncope provoking factors and prodromal signs in patients with vasovagal syncope with consideration given to gender. Materials and methods: We investigated 80 patients (40 men and 40 women), aged 18–75 years with previously diagnosed vasovagal cause of syncope. History was obtained from all the patients, with consideration given to the total number of syncopal and presyncopal episodes and age at first syncope. Special attention was paid to the frequency of precipitating factors such as a supine, sitting or standing position, activity and prodromal signs. Results. In the studied group, the mean age at first syncope was significantly lower in women (23.2 ± 10.7) as compared to men (30.7 ± 17.4). The mean total number of syncopal and presyncopal episodes was higher in women (13.3 ± 11.0 vs. 7.8 ± 6.6, p = 0.02; 26.6 ± 22.9 vs. 13.8 ± 26.9, p = 0.01) (Table 1). In the group of men, syncopal episodes were more frequent after urination and defecation. The remaining circumstances related to syncope were more prevalent in women, but only the occurrence of a syncopal episode during walking achieved statistical significance. All the prodromal signs that were analysed occurred more frequently in the group of women compared to men. Statistical significance was achieved for the analysed signs such as generalized weakness, dyspnea, heart palpitations, cold sweats, feeling of cold or heat, visual disturbances, tinnitus, headache (Table 2). Conclusions. Syncope provoking factors and prodromal signs occur more frequently in women.

Table 1. Clinical characteristics of the study group

Parameter	Whole studied group n = 80X ± SD	Men n = 40X ± SD	Women n = 40X ± SD	p (women vs. men)
Age (±SD) in years	43 ± 16.5	44.6 ± 16.6	42.1 ± 16.6	0.01
Weight	72.4 ± 14.0	81.5 ± 11.7	63.7 ± 10.5	<0.0001
Height	168.4 ± 9.5	177.3 ± 6.8	162.7 ± 5.9	<0.0001
BMI	24.6 ± 4.0	25.7 ± 3.8	23.9 ± 4.1	NS
Age at first syncope (years)	27.1 ± 14.2	30.7 ± 17.4	23.2 ± 10.7	0.01
Number of syncopal episodes before admission	11.1 ± 10.4	7.8 ± 6.6	13.3 ± 11.0	0.02
Number of presyncopal episodes	18.3 ± 25.6	13.8 ± 26.9	26.6 ± 22.9	0.01

Table 2. Frequency of triggering factors in the studied groups

Parameter	Whole studied group n = 80n (%)	Men n = 40n (%)	Women n = 40n (%)	p (women vs. men)
Syncope in a standing position n (%)	62 (77.5)	30 (75)	32 (80)	NS
Syncope in a sitting position n (%)	34 (42.5)	15 (37.5)	19 (47.5)	NS
Syncope in a standing position n (%)	3 (3.8)	1 (2.5)	2 (5)	NS
Syncope during walking n (%)	34 (42.5)	12 (30)	24 (55)	0.01
Syncope after urination n (%)	3 (3.8)	3 (7.5)	0	0.001
Syncope after Defecation n (%)	7 (8.8)	4 (10)	3 (7.5)	NS
Prodromal signs n (%)	73 (91.3)	36 (90)	37 (92.5)	NS
General weakness n (%)	49 (61.3)	22 (55)	27 (67.5)	0.02
Dyspnea n (%)	46 (57.5)	20 (50)	26 (66)	0.01
Heart palpitations n (%)	45 (56.3)	19 (47.5)	26 (65)	0.01
Cold sweats n (%)	37 (46.3)	11 (27.5)	26 (65)	0.001
Feeling of hot/cold n (%)	42 (52.5)	18 (45)	24 (60)	0.002
Visual disturbances n (%)	56 (70)	27 (67.5)	29 (72.5)	0.01
Dizziness n (%)	43 (53.8)	21 (52.5)	17 (42.5)	NS
Tinnitus n (%)	35 (43.8)	13 (32.5)	22 (55)	0.01
Headache n (%)	27 (33.8)	11 (27.5)	16 (40)	0.02
Stomachache n (%)	13 (16.3)	5 (12.5)	8 (20)	NS
Nausea n (%)	28 (35)	13 (32.5)	15 (37.5)	NS

16–19 Abstract 10–16

182 COMPARISON OF SYNCOPE PRODROMAL SIGNS REPORTED DURING HEAD-UP TILT TEST WITH OCCURRING BEFORE SPONTANEOUS SYNCOPAL EPISODES IN PATIENTS WITH VASOVAGAL SYNCOPE

Piotr Stryjewski¹, Agnieszka Kuczaj², Ryszard Braczkowski³, Jadwiga Nessler⁴, Bohdan Nessler⁴, Ewa Nowalany-Kozielska²

¹ Cardiology Department, Chrzanow City Hospital, Poland, Chrzanow, Poland; ² 2nd Department of Cardiology, Zabrze, Medical University of Silesia, Katowice, Poland, Zabrze, Poland; ³ Silesian Medical University, School of Public Health, Department of Public Health Bytom, Poland, Bytom, Poland; ⁴ Coronary Disease Department, Institute of Cardiology, Medical School of Jagiellonian University, John Paul II Hospital, Cracow, Poland, Krakow, Poland

Background. The aim of the study was a comparative analysis of syncope prodromal signs in patients with vasovagal syncope during head-up tilt test (HUTT) and their relationships with those reported before spontaneous episodes. Materials and methods. We investigated 80 patients (40 men and 40 women), aged 18–75 years with previously diagnosed vasovagal cause of syncope. In all the patients, clinical history according prodromal signs occurring before spontaneous syncopal episode and during HUTT was taken. Frequencies of occurrence of prodromal signs such as the following were analysed: general weakness, dyspnea, heart palpitation, cold sweats, feeling of hot/cold, visual disturbances, dizziness, tinnitus, headache and stomachache. Results. Prodromal signs were reported more frequently during HUTT when compared with spontaneous syncopal episode (91.3 vs. 98.8 %, p = 0.001). All the prodromal signs that were analysed occurred more frequently during head-up tilt test. Statistical significance was achieved for the analysed signs such as heart palpitations, dizziness and tinnitus (Table 1). Conclusions. Prodromal signs occur more frequently during HUTT when compared with spontaneous syncopal episodes.

Table 1. Occurrence of prodromal signs before spontaneous syncopal episode and during tilt test in patients with vasovagal syncope

Parameter	Spontaneus syncope (%)	HUTT n (%)	p
Prodromal signs n (%)	73 (91.3)	78 (98.8)	0.001
Dyspnea n (%)	46 (57.5)	52 (65)	NS
Heart palpitations n (%)	45 (56.3)	66 (82.5)	0.001
Cold sweats n (%)	37 (46.3)	43 (53.8)	NS
Feeling of hot/cold n (%)	42 (52.5)	48 (60)	NS
Visual disturbances n (%)	56 (70)	59 (73.8)	NS
Dizziness n (%)	43 (53.8)	61 (76.25)	0.001
Tinnitus n (%)	35 (43.8)	52 (65)	0.001
Headache n (%)	27 (33.8)	31 (38.8)	NS
Stomachache n (%)	13 (16.3)	17 (21.3)	NS
Nausea n (%)	28 (35)	32 (40)	NS

Ablation of ventricular arrhythmias

16–20 Abstract 28–17

183 ROLE OF NEGATIVE CONCORDANCE OF UNIPOLAR AND BIPOLAR ELECTROGRAMS IN THE SINGLE CATHETER DETERMINATION OF SITE OF ORIGIN OF FOCAL ARRHYTHMIAS

Gianluca Epicoco¹, Antonio Sorgente¹, Hussam Ali¹, Gianluca Bonitta¹, Sara Foresti¹, Guido De Ambroggi¹, Cristina Balla¹, Pierpaolo Lupo¹, Riccardo Cappato¹

¹ IRCCS Policlinico San Donato, San Donato Milanese, Italy

Introduction. The relevance of the temporal relationship between unipolar (UEGM) and bipolar electrograms (BEGM) in determining the site of origin of focal arrhythmias has been largely demonstrated. We sought to demonstrate that also a negative concordance in the initial forces of EGM is helpful in predicting the success of radiofrequency (RF) catheter ablation of these arrhythmias. Methods. Mapping and RF ablation were performed in 29 patients with focal premature ventricular contractions (PVC). At 201 mapping sites, where RF application was attempted, simultaneous recordings of minimally filtered UEGM (0.5–500 Hz) and filtered BEGM (30–500 Hz) were analyzed. A negative concordance between UEGM and BEGM was defined as the presence of a negative deflection during the first 20 ms of each EGM (black arrows, Figure 1). Two-sided Fisher exact test compared mapping sites with concordance with those without it. Results. RF ablation obtained PVC suppression in 23 sites (23/201, 11 %). At 22 out of 23 sites, a negative concordance of the initial forces of UEGM and BEGM was found (22/23 sites vs 1/169, p < 0,005) with a sensitivity of 96 % and a specificity of 97 %. The positive predictive and negative predictive values were 76 and 100 %, respectively. Conclusion. A negative concordance between initial forces of UEGM and BEGM on top of EGM temporal relationship assessment may be considered a valid technique useful to identify the site of origin of focal arrhythmias.

16–21 Abstract 17–11

184 RELATION BETWEEN SITE OF ORIGIN OF MONOMORPHIC VENTRICULAR ARRHYTHMIAS AND MYOCARDIAL TISSUE CHARACTERISTICS IN NON-ISCHEMIC LEFT VENTRICULAR HEART DISEASE

Daniele Muser¹, Piergiorgio Masci², Gianluca Piccoli¹, Luca Rebellato¹, Domenico Facchin¹, Mauro Toniolo¹, Massimo Lombardi², Alessandro Proclemer¹, Gaetano Nucifora¹

¹ Azienda Ospedalieera Santa Maria della Misericordia, Udine, Italy; ² Gabriele Monasterio Foundation-CNR Region Toscana, MRI Laboratory, Pisa, Italy

Purpose: Left ventricular (LV) scar is a potential substrate for ventricular arrhythmias (VAs). Analysis of QRS morphology on ECG during VA has been demonstrated to accurately identify the site of origin of monomorphic VA among patients with ischemic LV scar. The aim of the present study was to investigate the relation between site of origin of monomorphic VA and myocardial tissue characteristics among pts with non-ischemic LV structural heart disease. Methods: Twenty-six consecutive patients (96 % males, mean age 48 ± 13 years) with monomorphic VAs (i.e. frequent ventricular premature beats, recurrent non-sustained and sustained ventricular tachycardia) and non-ischemic LV structural heart disease were included in the study. Non-ischemic LV structural heart disease was defined on the basis of (1) cardiac magnetic resonance imaging (cMRI) evidence of LV late gadolinium enhancement (LGE), a surrogate of scar, with non-ischemic (intramyocardial or subepicardial) distribution, and (2) absence of significant coronary artery disease on exercise stress testing, multi-slice computed tomography or invasive coronary angiography. Site of origin of VA was identified analyzing QRS morphology on ECG during VA as previously suggested by Segal and colleagues (J Cardiovasc Electrophysiol. 2007;18:161–168). The relation between site of origin of VA and myocardial tissue characteristics as evaluated by cMRI was investigated. Results: Mean LVEDV and mean RVEDV were 96 ± 24 ml/m² and 80 ± 13 ml/m², respectively. LV dilatation was observed in 10 (38 %) patients; none had RV dilatation. Mean LVEF and mean RVEF were 57 ± 12 and 67 ± 8 %, respectively. Reduced LV and RV systolic function were observed in 14 (54 %) and 1 (4 %) patients, respectively. Mean number of LV segments with LGE per patient was 4.8 ± 3.8. A total of 127 (28 %) LV segments showed LGE; 42 LV segments had intramyocardial LGE and 71 LV segments had subepicardial LGE. Site of origin of VA was located at basal- or mid-posterior LV wall in 17 (65 %) patients, posteroapical LV wall in 4 (15 %) patients, mid-anterior LV wall in 1 (4 %) patient and basal- or mid-septum in 4 (15 %) patients. Site of origin of VA matched with the presence of LV LGE in 22 (85 %) patients. At the site of origin of VA, LGE was intramyocardial in 6 and subepicardial in 16 patients. Conclusions: In patients with non-ischemic LV structural heart disease, VAs usually originate from scar zone. In these patients, identification of scar using cMRI with LGE technique may be of value for mapping and ablation procedures.

16–22 Abstract 28–21

185 PROCEDURAL BENEFIT OF SUBSTRATE BASE ABLATION VERSUS CONVENTIONAL MAPPING AND ABLATION OF CLINICAL STABLE VENTRICULAR TACHYCARDIA: RESULTS FROM THE VISTA RANDOMIZED TRIAL

Luigi Di Biase¹, J. David Burkhardt², Dhanujaya R. Lakkireddy³, Corrado Carbucicchio⁴, Sanghamitra Mohant² Chintan Trivedi², Prasant Mohanty², Pasquale Santangeli², Rong Bai², Giovanni Forleo⁵, Rodney Horton² Shane Bailey², Javier Sanchez², Amin Al-Ahmad² Patrick Hranitzky², Gemma Pelargonio⁶, Richard Hongo, Salwa Beheiry⁷, Steven Hao⁷, Madhu Reddy³, Antonio Rossillo⁸, Sakis Themistoclakis⁸, Antonio Dello Russo⁴, Claudio Tondo⁴, Andrea Natale²

1 . Albert Einstein Coll of Med at Montefiore Hosp And Texas Cardiac Arrhythmia Inst at St David’s Medical Ctr, New York and Austin, TX, USA; 2 . Texas Cardiac Arrhythmia Inst at St. David’s Medical Ctr, Austin, TX, USA; 3. Univ of Kansas Medical Ctr, Kansas City, KS, USA; 4 Cardiac Arrhythmia Res Ctr, Ctr Cardiologico Monzino, IRCCS, Milan, Italy; 5 . Univ of Tor Vergata, Rome, Italy; 6 . Catholic Univ of the Sacred Heart - Insitute of Cardiology, Rome, Italy; 7 . California Pacific Medical Ctr, San Francisco, CA, USA; 8. Ospedale Dell’Angelo - Mestre, Mestre-Venice, Italy

Introduction: Catheter ablation of ventricular tachycardia (VT) in patients with ischemic cardiomyopathy (IC) represents a valid therapeutic option to AADs to reduce ICDs shocks and freedom from VT.

We sought to evaluate whether a substrate based ablation approach produce procedural benefit when compared to conventional ablation of the clinical VT in a randomized prospective trial.

Methods: This was an open-label, randomized, multicenter study. Patients were randomly assigned (1:1 ratio) to undergo ablation only of the presenting clinical VT at the site of the critical isthmus (group 1) versus a substrate-based ablation approach (group 2). Substrate ablation was empirically extended throughout the entire scar to target all “abnormal” electrograms. Procedural parameters were collected and analyzed.

Results: The final study population was composed by 118 patients (60 patients assigned to group 1, and 58 to group 2). The clinical baseline characteristics were not different between groups. The mean cycle length of the induced clinical VTs was 410 ± 90 ms in group 1 and 399 ± 86 ms in group 2 (p = 0.49). In group 2, pre ablation induction was not required by protocol and was performed in 22 patients. The procedural (4.6 ± 1.6 and 4.2 ± 1.3 h [p = 0.14]) and fluoroscopy time (28 ± 16 and 35 ± 32 min, p = 0.13) were not statistically different between groups. However, after removing group II patients where induction of VT was performed (22 cases), the procedural time decreased to 3.4 ± 1.7 h, which was significantly shorter than in group I [(4.2 ± 1.3 vs. 3.4 ± 1.7), p = 0.018]. Radiofrequency time was substantially longer in group 2 (35 ± 27 and 68 ± 21 min [p < 0.001]). In addition, cardiopulmonary support for hemodynamically unstable patients was used in 8 patients in group 1 and none in group 2.

Conclusion: This is the first randomized trial showing that a substrate based ablation approach allows ablation in sinus rhythm with a shorter procedural time and better hemodynamic stability for the patients.

16–23 Abstract 18–29

186 CATHETER-INDUCED MECHANICAL TRAUMA DURING ABLATION OF OUTFLOW TRACT VENTRICULAR ARRHYTHMIAS: INCIDENCE AND CLINICAL IMPLICATIONS.

Jeremy Ben-Shoshan¹, Yoav Michowitz¹, Aharon Glick¹, Bernard Belhassen¹

¹ Tel-Aviv Medical Center, Tel-Aviv, Israel

INTRODUCTION: The incidence and significance of catheter-induced trauma to ventricular arrhythmias (VA) originating from the outflow tract (OT) area during radiofrequency ablation (RFA) have not been described yet. METHODS: Consecutive patients (n = 340; 48 % females, aged 57 ± 11.6 years) undergoing RFA of right/left OT-VA (total 364 RFA procedures; 290 RVOT-VA and 74 LVOT-VA) were closely monitored for appearance of mechanical block of VA during catheter manipulation. RESULTS: Mechanical trauma to OT-VA was observed in 9 (2.4 %) patients (55 % females, aged 53.2 ± 12 years): in 8 patients during RVOT ablation (2.8 % procedures) and in 1 patients during LVOT ablation (1.3 % procedures) (p = NS). Catheter-induced trauma was due to the ablation catheter in all pts. In 3 patients who underwent >1 procedure, catheter-mechanical trauma occurred in only 1 procedure. In 3 patients (group I), the arrhythmia recurred spontaneously within a few minutes and was subsequently successfully ablated. In the remaining 6 patients (group II), RF was delivered at the site of the presumed catheter-induced trauma. In all 9 patients, the RFA procedure was acutely successful. However, the arrhythmia recurred during follow-up in 3 of 6 group II patients while no recurrence was recorded in all 3 group I patients. CONCLUSIONS: Catheter-induced mechanical trauma occurs in a small percentage of pts with OT-VA during RFA. Its occurrence may influence the results of the course of the ablation procedure. RFA of OT-VA guided by catheter-induced trauma may correlate with a high rate of long-term VA recurrence.

16–24 Abstract 18–27

187 REMOTE MAGNETIC NAVIGATION VERSUS MANUALLY CONTROLLED CATHETER ABLATION OF RIGHT VENTRICULAR OUTFLOW TRACT VENTRICULAR ARRHYTHMIAS: A RETROSPECTIVE SINGLE CENTER EXPERIENCE

Ayelet Shauer¹, Jorge Palazzolo¹, Mohammed Shurrab¹, Sheldon Singh¹, Ilan Lashevsky¹, Irvin Tiong¹, David Newman¹, Eugene Crystal¹

¹ Sunnybrook Health Sciences Centre, Toronto, Canada

BACKGROUND: Remote magnetic navigation (RMN) has been introduced as an alternative to manual catheter control (MCC) radiofrequency ablation of right ventricular outflow tract (RVOT) arrhythmia. The comparative data to support RMN approach are limited, especially so for the novel platform of RMN EpochTM. OBJECTIVE: The aim of this study was to retrospectively evaluate the clinical and procedural outcomes in a cohort of patients undergoing RVOT PVCs/VT ablation procedures using RMN vs. MCC. METHODS: Thirty-seven consecutive patients (mean age 53, range 23–84 years, 16 females) who had RVOT PVCs/VT ablation were included (RMN 20 patients vs MCC 17 patients). Endocardial mapping using CARTOXPTM or CARTO3 (Biosense Webster) was used in 6/20 (30 %) in RMN group and 6/17 (35 %) in MCC group; EnSiteTM NavXTM (St. Jude Medical) system was used in the rest of the cohort. NiobeTM II EpochTM platform (Stereotaxis Inc, St. Louis, MO) was used for RMN approach. RESULTS: The procedural time was 109 ± 66 min in the RMN group and 109 ± 71 min MCC (p = 0.98). However, total fluoroscopic time was 10.0 ± 7.1 min in RMN vs. 17.6 ± 8.8 in MCC group (p = 0.01). Total ablation energy application time was 9.4 ± 5.2 min in RMN vs. 9.7 ± 6.0 min in RCC (p = 0.88). There were no complications in the RMN group and four tamponade events in the MCC group (p = 0.04). Acute procedural success rate was 75 % in RMN vs 76 % in MCC group (p = 1.0). Long-term success was available for 32 of the 37 patients. The success rate during median follow-up of 10.2 ± 5.9 months was 63 % in both groups (P = 1.0) CONCLUSION: RVOT arrhythmia ablation using novel platform of RMN demonstrates lower fluoroscopic time and lower tamponade rate than ablation with manual approach. Acute and long-term success rate are not significantly different.

16–25 Abstract 18–23

188 SIMULTANEOUS UNIPOLAR RADIOFREQUENCY ABLATION OF VENTRICULAR TACHYCARDIA USING TWO ABLATION CATHETERS

Vivek Iyer¹, Alok Gambhir¹, Shalin P. Desai¹, Hasan Garan¹, William Whang¹

¹ Columbia University Medical Center, New York, NY, USA

Catheter ablation of ventricular tachycardia (VT) has become a cornerstone in the management of patients with refractory episodes. However, incomplete penetration into the VT substrate may account for a large proportion of acute procedural failure. We present a case of incessant VT mapped to the ventricular septum, which was initially unsuccessfully controlled with an attempt at endocardial catheter ablation. Subsequently, in a repeat procedure, the VT was targeted using simultaneous unipolar radiofrequency (SURF) ablation with an ablation catheter on each side of the ventricular septum, with acute procedural success and long-term control of arrhythmia. To our knowledge, this is the first report of successful arrhythmia termination with SURF in a patient. RF delivery in this configuration produces intramural heating via synchronous resistive tissue heating at each catheter-myocardium interface (which can be optimized by tissue contact force and power delivery) and conductive heating to the midpoint of the muscle wall from opposing directions. This theoretically differs from sequential unipolar delivery in that the “heat sink” on the opposing tissue aspect (as occurs with sequential unipolar ablation) is replaced with another heat “source” (namely, simultaneous heating via the second catheter), which may produce higher intramural tissue temperatures during an application. Possible risks and limitations of the approach are discussed, and SURF ablation is placed in the context of alternative options in the management of the inaccessible substrate (including the bipolar configuration, intramyocardial techniques such as the needle electrode, and ethanol delivery). We conclude that SURF ablation may be an effective option in the management of VT refractory to conventional unipolar ablation.

16–26 Abstract 14–13

189 EFFICACY AND SAFETY OUTCOMES OF VARIOUS RATE CONTROL STRATEGIES FOR PATIENTS WITH ACUTE DECOMPENSATED HEART FAILURE WITH REDUCED EJECTION FRACTION AND ATRIAL FIBRILLATION OR FLUTTER WITH RAPID VENTRICULAR RESPONSE

Lee Joseph¹, Siva Krothapalli¹, Omer Iqbal¹, Olurotimi Mesubi¹, Hardik Doshi¹, Nicole Worden¹, Jayasheel Eshcol¹, Musab Alqasrawi¹, Prashant Bhave¹, Michael Giudici¹

¹ University of Iowa, Iowa City, IA, USA

Background: There is no current evidence regarding the safety and efficacy of various rate control strategies for rapid atrial fibrillation or atrial flutter (AF/AFL; heart rate >100 bpm) in hospitalized patient with acute decompensated heart failure with reduced ejection fraction (ADHFrEF). Methods: Single center retrospective study of hospitalized patients with ADHFrEF and rapid AF/AFL. Results: We included 52 patients with ADHFrEF and rapid AF/AFL (mean age, 64.3 ± 13.9 years; 39 (75 %) males; mean left ventricular EF [%], 29.4 ± 8.1; median follow up duration [months], [13] (IQR, 5.3–19): 42 (80.8 %) received beta blockers (BB), 10 (19.2 %) calcium channel blockers (CCB), 22 (42.3 %) digoxin and 2 (3.8 %) had AV node ablation and pacemaker (PPM) implantation. Patients treated with BB had significant higher rates of survival to hospital discharge, median follow-up and lower procedural complications. There was an increase in survival rate to discharge in those treated with digoxin. There were no significant differences in symptom control, thromboembolism, worsening heart failure and mean length of hospital stay between patients treated with and without BB, CCB, digoxin and AV node ablation followed by PPM implantation (Table 1). Conclusion: Treatment with BB and digoxin for acute control of rapid AF/AFl appears to improve survival to hospital discharge and median follow up in hospitalized patients with ADHFrEF.

Table 1: Efficacy and safety outcomes of various rate control strategies for patients with acute decompensated heart failure with reduced ejection fraction and atrial fibrillation or flutter with rapid ventricular response (N = 52)

Outcome	Beta blocker			Calcium channel blocker			Digoxin [PB1]			Atrioventricular node ablation and permanent pacemaker placement
	Yes	No	P value	Yes	No	P value	Yes	No	P value	Yes	No	P value
Survival to mean follow up, N (%)	33 (78.6)	4 (40)	0.016	9 (90)	25 (56.8)	0.275	18 (81.8)	19 (63.3)	0.146	2 (100)	35 (70)	0.358
Survival to hospital discharge, N (%)	34 (80.9)	5 (50)	0.042	10 (100)	25 (56.8)	0.068	20 (90.9)	19 (63.3)	0.023	2 (100)	37 (74)	0.405
Symptom control, N (%)	34 (80.9)	5 (50)	0.501	10 (100)	29 (65.9)	0.248	17 (77.3)	22 (73.3)	0.230	2 (100)	37 (74)	0.643
Length of hospitalization, median (IQR)	5 (6)	5.5 (11)	0.935	6.5 (8)	4 (6)	0.288	6 (11)	5 (5)	0.448	0.5 (−)	5 (6)	0.541
Major bleeding event, N (%)	1 (2.4)	1 (10)	0.260	0 (0)	2 (4.5)	0.432	0 (0)	2 (6.7)	0.217	0 (0)	2 (4)	0.773
Systemic embolism, N (%)	3 (7.1)	0 (0)	0.384	1 (10)	1 (2.3)	0.346	0 (0)	3/(10)	0.127	0 (0)	3 (6)	0.721
Worsening heart failure, N (%)	17 (40.5)	4 (40)	0.826	5 (50)	14 (31.8)	0.673	11 (50)	10 (33.3)	0.174	2 (100)	19 (38)	0.085
Procedure related complication, N (%)	0 (0)	2 (20)	0.000	0 (0)	2 (4.5)	0.401	0 (0)	2 (6.7)	0.193	0 (0)	2 (4)	0.724

16–27 Abstract 31–12

190 RHYTHM VERSUS RATE CONTROL FOR PATIENTS WITH ACUTE DECOMPENSATED HEART FAILURE WITH REDUCED EJECTION FRACTION AND ATRIAL FIBRILLATION OR FLUTTER WITH RAPID VENTRICULAR RESPONSE

Lee Joseph¹, Nicole Worden¹, Jayasheel Eshcol¹, Hardik Doshi¹, Siva Krothapalli¹, Omer Iqbal¹, Olurotimi Mesubi¹, Musab Alqasrawi¹, Prashant Bhave¹, Michael Giudici¹

¹ University of Iowa, Iowa City, IA, USA

Background: The best approach for acute control of rapid atrial fibrillation or flutter (AF/AFL; heart rate >100 bpm) in hospitalized patients with acute decompensated heart failure with reduced ejection fraction (ADHFrEF) has not been previously studied, and remains a challenge owing to the neutral results of prior studies comparing rhythm versus rate control strategies. Objectives: The study aims to compare the safety and efficacy of rhythm versus rate control strategies for acute control of rapid AF/AFL in hospitalized patients with ADHFrEF. Methods: A single center retrospective study of hospitalized patients with ADHFrEF and rapid AF/AFL. Results: We identified 52 patients with ADHFrEF and rapid AF/AFL (age, 64 ± 14 years; 39 (75 %) males; left ventricular EF [%], 29.4 ± 8.1; median follow-up duration [months], 13 [IQR, 5.3–19]): 40 (76.9 %) received a rhythm control strategy and 12 (23.1 %) a rate control strategy. There was no significant differences in the survival rates at follow-up, survival to hospital discharge, symptom control, major bleeding event, systemic embolism, worsening heart failure, procedure-related complications, and mean length of hospital stay between the rate and rhythm control groups (Table 1). Conclusion: Acute control of rapid AF/AFL in hospitalized patients with ADHFrEF using a rhythm control strategy does not improve the survival and morbidity outcomes over a rate control strategy in this study, and both may have similar safety and efficacy profiles in this critically ill population.

Table 1. Rhythm versus rate control for patients with acute decompensated heart failure with reduced ejection fraction and atrial fibrillation or flutter with rapid ventricular response

Outcome	Rate control (N = 12)	Rhythm control (N = 40)	P value
Survival to mean follow up, N (%)	8 (66.7)	29 (72.5)	0.696
Survival to hospital discharge, N (%)	9 (75.0)	30 (75)	1.000
Symptom control, N (%)	8 (66.7)	31 (77.5)	0.834
Length of hospitalization, median days (IQR)	4.0 (10)	5.0 (7)	0.980
Major bleeding event, N (%)	0 (0)	2 (0.05)	0.430
Systemic embolism, N (%)	1 (8.3)	2 (0.05)	0.664
Worsening heart failure, N (%)	5 (41.7)	16 (40)	0.969
Procedure related complication, N (%)	0 (0)	2 (0.05)	0.515

16–28 Abstract 06–10

191 THE LUNG IMPEDANCE MONITORING IN TREATMENT OF CHRONIC HEART FAILURE: PRELIMINARY RESULTS FROM THE LIMIT-CHF STUDY

Giulia Domenichini¹, Cveta Rahneva¹, Ihab Diab¹, Onkar Dhillon¹, Victoria Baker¹, Ross Hunter¹, Mark Earley¹, Richard Schilling¹

¹ Department of Cardiology, St Bartholomew’s Hospital, London, UK

Background: The study aims to assess the usefulness of intra-thoracic impedance monitoring (IIM) alerts in guiding medication therapy in chronic heart failure (CHF) patients to prevent hospitalisations. Methods: CHF patients with OptiVol® or CorVue™ capable ICDs were randomised to either the active group (IIM alarm turned on and diuretic dose increased by 50 % for 1 week) or the control group (IIM alarm turned off). The primary endpoint was the number of hospitalisations or acute unscheduled care episodes at 1 year. The NYHA class, 6-min walk test (6MWT), BNP and Minnesota Living with HF (MLWHF) questionnaire score were collected at baseline and follow-up. Results: Eighty patients were included and 71 reached 1-year follow-up (7 patients died, 1 patient was lost at follow-up and 1 patient was excluded from analysis since the congestion data were not collected by the device). The baseline characteristics and study outcomes are shown in the Table. In the active group, 55.9 % (33/59) of alerts lead to increasing the diuretic dose. There was a total of 14 endpoint episodes in the active group vs. 8 in the control group without significant differences in the number of episodes per patient (0.4 ± 1.0 vs. 0.2 ± 0.4, p = 0.70). There was a moderate but significant reduction in heart failure-related quality of life scores. Conclusion: In this study, IIM did not reduce emergency treatment of heart failure; however, there was a positive impact on quality of life. This technology may have a useful role in managing heart failure patients with implantable devices.

	Active group (n = 36)	Control group (n = 35)	p
Age (years)	70 ± 11	66 ± 12	0.20
LVEF (%)	29 ± 8	28 ± 7	0.39
CRT-devices (%)	61	71	0.50
No. of alerts/patient	16 ± 1.4	1.2 ± 1.0	0.19
ΔNYHA	0.0 (−2.0–1.5)	0.0 (−1.0–1.0)	0.61
Δ6MWT (m)	−35 ± 97	−14 ± 57	0.78
ΔBNP (pg/mL)	−3 ± 193	2 ± 144	0.80
ΔMLWHF	−5 ± 16	5 ± 12	0.005

16–29 Abstract 15–23

192 OUTCOMES OF RHYTHM CONTROL FOR ATRIAL FIBRILLATION/FLUTTER IN ACUTE DECOMPENSATED HEART FAILURE

Jayasheel Eshcol¹, Michael Giudici¹, Lee Joseph¹, Nicole Worden¹, Musab Alqasrawi¹, Hardik Doshi¹, Omer Iqbal¹

¹ University of Iowa Hospitals and Clinics, Iowa City, IA, USA

Background: The safety and efficacy of rhythm control strategies for the management of atrial fibrillation or flutter (AF/AFL) in patients with acute decompensated heart failure with reduced ejection fraction (ADHFrEF) has not been established. It is unclear if there is a difference in outcomes between various rhythm control strategies such as amiodarone and other anti-arrhythmic drugs (AAD), electrical cardioversion, catheter-based ablation and permanent pacemaker (PPM) placement with AAD. Objectives: The study aims to report the safety and efficacy outcomes of different rhythm control strategies for acute control of rapid AF/AFL in hospitalized patients with ADHFrEF. Methods: A retrospective cohort study of patients hospitalized with ADHFrEF and rapid AF/AFL in a single center over a 2-year period, median follow-up 13 months [interquartile range, 5.3–19]. Results: Fifty-two patients hospitalized with ADHFrEF and rapid AF/AFL managed with a rhythm control strategy were identified [mean age 64.3 ± 13.9 years; 39 (75 %) males; mean left ventricular EF 29.4 ± 8.1 %]. Thirty patients (57.7 %) received amiodarone, 1 (1.9 %) received other AAD, 19 (36.5 %) received electrical cardioversion, and none received PPM. There were 10 (19.2 %) patients who received catheter ablation, all of which had AFL. No differences were observed between rhythm control strategies for AF in time to effective symptom control, in-hospital survival, worsening heart failure, mean length of stay, systemic embolism, major bleeding event or procedure related complications (Table 1). Patients who were treated with catheter-based ablation had significantly higher rates of survival to discharge and to median follow-up. New onset AF/AFL, new onset heart failure, left ventricular ejection fraction, New York Heart Association functional class, and loading with AAD did not predict response to electrical cardioversion (Table 2). Conclusion: Catheter-based ablation of atrial flutter improved survival in patients hospitalized with ADHFrEF. Rhythm control strategy is a reasonable choice with few adverse events in the management of rapid AF/AFL in these patients.

Table 1. Rhythm control strategies for patients with acute decompensated heart failure with reduced ejection fraction and atrial fibrillation or flutter with rapid ventricular response

Outcome	Amiodarone			Electrical cardioversion			Catheter ablation (AFL)
	Yes	No	P value	Yes	No	P value	Yes	No	P value
Survival to mean follow up, N (%)	19 (63.3)	18 (81.8)	0.146	15 (78.9)	22 (66.7)	0.347	10 (100)	27 (64.3)	0.025
Survival to hospital discharge, N (%)	20 (66.7)	19 (86.4)	0.105	17 (89.5)	22 (66.7)	0.067	10 (100)	29 (69.0)	0.042
Symptom control, N (%)	22 (73.3)	17 (77.3)	0.473	15 (78.9)	24 (72.7)	0.653	8 (80)	31 (73.8)	0.834
Length of hospitalization, median days (IQR)	5.5 (7)	5 (7)	0.713	4 (7)	6 (6)	0.463	2.5 (5)	5.5 (10)	0.431
Major bleeding event, N (%)	2 (6.7)	0 (0)	0.217	1 (5.3)	1 (3.0)	0.687	0 (0)	2 (4.8)	0.482
Systemic embolism, N (%)	1 (3.3)	2 (9.1)	0.379	2 (10.5)	1 (3.0)	0.264	0 (0)	3 (7.1)	0.384
Worsening heart failure, N (%)	12 (40)	9 (40.9)	0.973	10 (52.6)	11 (33.3)	0.200	4 (40)	17 (40.5)	0.933
Procedure related complication, N (%)	2 (6.7)	0 (0)	0.274	1 (5.3)	1 (3.0)	0.806	0 (0)	2 (4.8)	0.401

AUTHORS INDEX BY ABSTRACT NUMBER (original number given at submission)

Abraham J. et al. Abs. 25–10 Session C part 2

Al Anany AA. et al. Abs. 24–27 Session C part 1

Al Khiami B. et al. Abs. 24–18 Session C part 1

Ali RL. et al. Abs. 15–54 Session A part 2

Alonso-Martin C. et al. Abs. 18–17 Session A part 1, 15–22 Session A part 2

Aman W. et al. Abs. 18–18 Session B part 2

Anderson S. et al. Abs. 15–37 Session 5

Ang R. et al. Abs. 18–32 Session 1

Ardashev A. et al. Abs. 08–12 Session A part 1, 01–20 Session B part 2

Artyukhina E. et al. Abs. 14–17 Session A part 1

Backenkoehler U. et al. Abs. 19–13 Session C part 2

Bars C. et al. Abs. 18–26 Session 1

Bastian D. et al. Abs. 15–20 Session A part 2

Batalov R. et al. Abs. 14–16 Session 12

Baykaner T. et al. Abs. 04–13 Session 5

Behunin A. et al. Abs. 19–11 Session C part 2

Benova T. et al. Abs. 17–13 Session 4

Ben-Shoshan J. et al. Abs. 18–29 Session D part 2

Bisleri G. et al. Abs. 15–31 Session B part 2

Bonora A. et al. Abs. 15–24 Session A part 2

Bouzeman A. et al. Abs. 19–30 Session 2, 19–29 Session C part 2

Bunz B. et al. Abs. 15–14 Session B part 2

Campbell N. et al. Abs. 22–10 Session D part 1

de Groot N. et al. Abs. 28–10 Session B part 1

de Ruvo E. et al. Abs. 15–41 Session 5

Derndorfer M. et al. Abs. 17–14 Session 7

Dhanjal T. et al. Abs. 02–14 Session 4

Di Biase L. et al. Abs. 15–57 Session 3, 28–21 Session D part 2

Domenichini G. et al. Abs. 06–10 Session D part 2

Domenichini G. et al. Abs. 24–20 Session 6

Dooijes D. et al. Abs. 07–19 Session 8

Dubova A. et al. Abs. 01–22 Session D part 1

Efimova E. et al. Abs. 01–10 Session A part 1

Eichhorn C. et al. Abs. 02–13 Session 9

Epicoco G. et al. Abs. 28–17 Session D part 2

Eremeeva M. et al. Abs. 02–10 Session 10

Eshcol J. et al. Abs. 15–23 Session D part 2

Finlay M. et al. Abs. 04–14 Session B part 1

Fumagalli F. et al. Abs. 19–25 Session 2

Galati F. et al. Abs. 03–10 Session B part 1

Giudici M. et al. Abs. 23–10 Session D part 1

Goldenberg G. et al. Abs.14-11 Session 12

Gregers Winkel B. et al. Abs. 19–17 Session C part 2

Grett M. et al. Abs. 24–13 Session 6

Guiraudon G. et al. Abs. 15–26 Session 9

Guliaeva E. et al. Abs. 01–17 Session B part 1

Haber T. et al. Abs. 18–13 Session B part 1

Härtig J. et al. Abs. 24–16 Session C part 1

Hayashi H. et al. Abs. 23–13 Session D part 1

Hodes AR. et al. Abs. 07–18 Session 8

Höltgen R. et al. Abs. 15–34 Session 11

Houck C. et al. Abs. 07–10 Session A part 1, 07–17 Session B part 1

Iqbal O. et al. Abs. 15–25 Session 3,31-11 Session C part 1

Iyer V. et al. Abs. 18–23 Session D part 2

Jacon P. et al. Abs. 19–22 Session C part 2

Jacquemet V. et al. Abs. 15–21 Session A part 2

Joseph L. et al. Abs. 14–13, 31–12 Session D part 2

Kalejs O. et al. Abs. 15–51 Session 3

Kanters J. et al. Abs. 01–15 Session C part 1

Khaliulin I. et al. Abs. 17–17 Session C part 1

Kim TH. et al. Abs. 31–10 Session 6, 09–10 Session A part 2

KIS Z. et al. Abs. 24–19 Session 6

Konrad T. et al. Abs. 15–42 Session A part 2

Kooiman KM. et al. Abs. 19–10 Session C part 2

Kumarathurai P. et al. Abs. 15–47 Session A part 2

Kutarski A. et al. Abs. 23–20, 23–24 Session D part 1

Lahiri M. et al. Abs. 25–11 Session C part 2

Lanters E. et al. Abs. 15–55 Session B part 1

Larsen B. et al. Abs. 14–20 Session 9

Lau E. et al. Abs. 24–24 Session C part 1, 19–28 Session C part 2

Lavanga S. et al. Abs. 15–44 Session A part 2

Le Bloa M. et al. Abs. 10–13 Session 2

Lee HC. et al. Abs. 02–12 Session 10

Levy W. et al. Abs. 19–26 Session 2

Ling Lh. et al. Abs. 15–36 Session 3

Litunenko O. et al. Abs. 15–52, 15–48 Session A part 2, 15–50 Session D part 1

Luik A. et al. Abs. 05–12 Session B part 1

Luther V. et al. Abs. 28–14, 18–19 Session 7, 28–13 Session A part 1

Mahjoub M. et al. Abs. 20–11 Session A part 1, 15–43 Session A part 2

Maines M. et al. Abs. 18–31 Session A part 1, 24–26 Session C part 1

Manani K. et al. Abs. 15–19 Session 9

Marchenko R. et al. Abs. 14–15 Session A part 1

Marrakchi S. et al. Abs. 15–56 Session B part 2

Martens E. et al. Abs. 19–23 Session C part 2

Martens E. et al. Abs. 19–24 Session 2

Martino A. et al. Abs. 14–19 Session A part 1, 07–16 Session B part 2

Mast TP. et al. Abs. 07–14 Session 8

Méndez Z F. et al. Abs. 31–15 Session C part 2

Michowitz Y. et al. Abs. 18–30 Session 11, 13–12 Session A part 1

Mikhaylichenko S. et al. Abs. 19–21 Session C part 2

Ming Wei Leong K. et al. Abs. 04–11, 04–12 Session B part 1

Möllenhoff C. et al. Abs. 15–33 Session 3

Monnier A. et al. Abs. 19–15 Session C part 2

Mouws E. et al. Abs. 17–12 Session B part 1

Muser D. et al. Abs. 17–10, Session 7, 24–14 Session 6,18-12 Session 12, 17–11 Session D part 2

Nagy-Baló E. et al. Abs. 15–12 Session 11

Ng FS. et al. Abs. 01–16 Session 4, 01–14 Session 10

Noseworthy P.et al. Abs. 18–21 Session 1

Park J. et al. Abs. 15–11 Session 11, 15–10 Session B part 2

Peyrol M. et al. Abs. 15–39 Session B part 2

Poci D. et al. Abs. 15–49 Session B part 1

Polewczyk A. et al. Abs. 23–12, 23–17, 23–11, 23–16 Session D part 1

Qureshi N. et al. Abs. 28–16 Session 5, 01–19 Session 10, 01–18 Session D part 1

Ragunath Shunmugam S. et al. Abs. 15–40 Session 5

Rebecchi M. et al. Abs. 10–15 Session D part 2

Revishvili A. et al. Abs. 15–32 Session 11, 28–15 Session A part 1

Roney CH. et al. Abs. 01–21, 14–21 Session 9, 15–53 Session A part 2, 05–14 Session B part 1

Saksena S. et al. Abs. 31–16 Session 6, 21–11 Session A part 2

Sami M. et al. Abs. 15–17 Session D part 1

Sandler B. et al. Abs. 04–10 Session C part 1

Sattler S. et al. Abs. 18–25 Session 1

Sawhney V. et al. Abs. 19–19 Session C part 1

Sciarra L. et al. Abs. 01–12 Session 4, 24–22 Session C part 1

Sebag F. et al. Abs. 24–23 Session C part 1

Selvadurai S. et al. Abs. 02–11 Session 4

Shauer A. et al. Abs. 18–27 Session D part 2

Shurrab M. et al. Abs. 18–14 Session 12

Siebermair J. et al. Abs. 18–24 Session B part 2, 19–20 Session C part 2

Sikkel M. et al. Abs. 28–19 Session B part 2

Skibsbye L. et al. Abs. 01–11 Session 10

Sorrel J. et al. Abs. 15–27 Session 11

Spaziani D. et al. Abs. 24–12 Session C part 1

Stryjewski PJ.et al. Abs. 10–10, 10–16 Session D part 2

Stute F. et al. Abs. 13–10 Session A part 1

Sugihara C. et al. Abs. 15–28 Session 3

Sugihara C. et al. Abs. 20–10 Session A part 2

Sun Y. et al. Abs. 15–18, 14–14 Session D part 1

te Riele AS. et al. Abs. 07–12 Session 8

Teres C. et al. Abs. 17–18 Session 7

Termosesov S. et al. Abs. 18–35 Session 7

Teunissen C. et al. Abs. 18–15 Session B part 2

Teunissen C. et al. Abs. 18–33 Session 12

Teuwen C. et al. Abs. 07–11 Session A part 1, 17–15 Session B part 1

Tordini A. et al. Abs. 18–28 Session 12

Ullah W. et al. Abs. 18–22 Session 1, 05–13 Session B part 2

Vado A. et al. Abs. 24–11 Session C part 1

Varlet E. et al. Abs. 07–15 Session 8

Varotto L. et al. Abs. 15–30 Session B part 2

Visser M. et al. Abs. 19–16 Session 2

Wakili R. et al. Abs. 15–35 Session B part 2

Winkle R. et al. Abs. 18–16 Session 1, 28–11 Session A part 1

Wolf CM. et al. Abs. 03–12 Session 8

Worden NE. et al. Abs. 19–18 Session C part 2

Yahalom M. et al. Abs. 08–14 Session B part 1

Yaksh A. et al. Abs. 14–12 Session B part 1

Yaksh A. et al. Abs. 31–13 Session D part 1

Yeoh A. et al. Abs. 01–23 Session 4

Zaman J. et al. Abs. 01–13 Session 10, 15–11 Session C part 1

Zaman J. et al. Abs. 15–46 Session 5, 28–18 Session B part 2