Session 4: pulsatile implantable devicesThe totally implantable Novacor Left Ventricular Assist System☆
Section snippets
Stanford clinical experience
The records of patients supported with the Novacor LVAS at Stanford University Medical Center from September 5, 1984 until September 10, 2000 were reviewed. The inflow conduits and outflow grafts that connect the pump between the left ventricular apex and ascending aorta were made of low porosity, woven polyester (Cooley, Meadox Medical, Oakland, NJ) from 1984 through 1997. Since 1998, a gelatin-sealed, knitted polyester graft with integral wall reinforcement, manufactured by Vascutek (Sulzer
Totally implantable LVAS preclinical animal studies
The totally implantable configuration of the Novacor LVAS was placed in 4 sheep. All animals received humane care in compliance with the “Guide for the Care and Use of Laboratory Animals” published by the National Institutes of Health (NIH Publication No. 85–23, revised 1985). The system consisted of a pump/drive unit, volume compensator, belt skin transformer, and controller/battery. The system was placed through a posterior-lateral thoracotomy with the inflow conduit inserted into the left
The Novacor II
Information on the Novacor II LVAS was obtained from World Heart Inc (Oakland, CA, US base of World Heart Corporation, Ottawa, Canada). The Novacor II LVAS concept represents an attractive approach for a totally implantable, definitive treatment of end-stage congestive heart failure. It has a dual-chambered pump (four total valves) and a shared pusher plate (Fig 2). The pusher plate is suspended and driven directly by a magnetic drive obviating the need for bearings, cams, or linkages. The
Comment
The objective of the initial design of the Novacor LVAS was to develop a totally implantable system to provide definitive therapy for end-stage congestive heart failure. The electrically powered, pulsatile Novacor LVAS has provided reliable, efficacious support as a bridge to transplantation. Worldwide, more than 1,170 patients have received the Novacor LVAS, 84 of whom have been supported for more than 1 year, with the longest duration of support being 4.1 years. Confirming reliability
References (3)
- et al.
Improved outcomes with an implantable left ventricular assist systema multicenter study
Ann Thorac Surg
(2001)
Cited by (43)
Evolving trends in mechanical circulatory support: Clinical development of a fully magnetically levitated durable ventricular assist device
2020, Trends in Cardiovascular MedicineCitation Excerpt :Initial devices included the TCI Heartmate 1000 IP and the Novacor device. The first generation devices attempted to mimic the pulsatility of a native heart and as such, were bulky and less durable due to numerous moving parts including valves within the inflow and outflow pathways [2]. These were followed by the Heartmate IP and subsequently, the Heartmate XVE, both of which afforded patients the ability to mobilize and rehabilitate [3].
Circulatory Assist Devices in Heart Failure
2011, Heart FailureCirculatory Assist Devices in Heart Failure
2010, Heart Failure: A Companion to Braunwald's Heart Disease Expert ConsultVentricular Assist Devices. The Challenges of Outpatient Management
2009, Journal of the American College of CardiologyCitation Excerpt :The entire VAD is susceptible to infection including the surgical site, device pocket, driveline, valves, and conduits. The most common site of infection is the percutaneous driveline, which can often be managed successfully with wound care and antibiotics (69). However, a driveline infection can spread to other components of the VAD resulting in bacteremia, sepsis, and endocarditis (Fig. 5)(70).
Mechanical Devices
2007, The Johns Hopkins Manual of Cardiac Surgical Care: Mobile Medicine SeriesVentricular assist device-related infections
2006, Lancet Infectious DiseasesCitation Excerpt :Prevention of ventricular assist device-related infections may help make ventricular assist device implantation more cost-effective.27 Ventricular assist device-related infections occur in 18–59% of patients after ventricular assist device implantation.17–23 In a literature review by Baddour and colleagues,29 infections have been reported to occur in 13–80% of cases.
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Drs Oyer and Portner are consultants to World Heart Inc, manufacturer of the Novacor assist system.