Clinical Research
Assessment of Right Ventricular Function in Obstructive Sleep Apnea Syndrome and Effects of Continuous Positive Airway Pressure Therapy: A Pilot Study

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Abstract

Background

It is known that obstructive sleep apnea syndrome (OSAS) can affect right ventricular (RV) performance even in the absence of systemic hypertension and other known cardiac or obstructive pulmonary disease. The purpose of the present study was to assess RV function in OSAS using 3-D echocardiography and speckle tracking echocardiography (STE) and evaluate changes after continuous positive airway pressure (CPAP) treatment.

Methods

Thirty-seven patients with OSAS without comorbidities and thirty control subjects were studied using 3-D echocardiography and STE. Fifteen patients underwent CPAP therapy and were studied before and after treatment. RV 3-D ejection fraction was calculated. Peak systolic strain was determined. RV dyssynchrony was defined as SD of the 6 time to peak systolic strain values.

Results

3-D RV ejection fraction was lower and RV dyssynchrony was greater in patients with moderate-severe OSAS compared with control subjects in the presence and absence of pulmonary hypertension. 3-D RV ejection fraction and RV dyssynchrony were independently associated with apnea-hypopnea index. Patients treated with CPAP had significant changes in RV parameters.

Conclusions

3-D RV ejection fraction and RV dyssynchrony were abnormal in OSAS patients compared with control subjects and associated with OSAS severity. RV 3-D STE abnormalities improved after chronic application of CPAP.

Résumé

Introduction

On sait que le syndrome de l’apnée obstructive du sommeil (SAOS) peut affecter la performance du ventricule droit (VD) même en l’absence d’hypertension systémique et d’autres maladies cardiaques ou pulmonaires obstructives. Le but de la présente étude était d’évaluer la fonction du VD lors du SAOS à l’aide de l’échocardiographie 3D et de l’échocardiographie Speckle Tracking (suivi de pixel; EST) et les changements après le traitement par pression positive expiratoire continue (CPAP).

Méthodes

Trente-sept patients souffrant du SAOS sans comorbidités et 30 sujets témoins ont été étudiés à l’aide de l’échocardiographie 3D et de l’EST. Quinze patients ont subi la thérapie CPAP et ont été étudiés avant et après le traitement. La fraction d’éjection du VD en 3D a été calculée. La déformation systolique maximale a été déterminée. La dyssynchronie du VD a été définie comme étant suérieure de 6 fois l'ET des valeurs maximales de déformation systolique.

Résultats

La fraction d’éjection du VD en 3D était plus faible et la dyssynchronie du VD était plus grande chez les patients souffrant du SAOS modéré à grave que chez les sujets témoins en présence ou en l’absence d’hypertension pulmonaire. La fraction d’éjection du VD en 3D et la dyssynchronie du VD étaient indépendamment associées à l’index d’apnées-hypopnées. Les patients traités par CPAP montraient des changements significatifs dans les paramètres du VD.

Conclusions

La fraction d’éjection du VD en 3D et la dyssynchronie du VD étaient anormales chez les patients souffrant du SAOS comparativement aux sujets témoins et associées à la gravité du SAOS. Les anomalies du VD en 3D à l’EST s’amélioraient après l’application à long terme du CPAP.

Section snippets

Methods

For detailed methodological information and statistical analysis, see the Methods section of the Supplementary Material.

A cohort of 37 sleep apnea patients without comorbidities and 30 control subjects were examined with polysomnography15 and echocardiography. Established echocardiographic criteria were used for assessment of right chambers.16, 17, 18, 19, 20, 21, 22, 23 Three-dimensional echocardiographic images (Fig. 1) were stored digitally for off-line analysis using dedicated software. STE

Results

Thirty-seven of 44 initially evaluated OSAS patients were included in the study. 3DE images of the right ventricle were successfully analyzed in 41 of 44 patients. Longitudinal 2D RV strain measurement from all segments because of adequate tracking quality was possible in 42 of 44 patients. 3-D feasibility was 93%, and 2D strain feasibility was 95%. Tricuspid regurgitation to estimate right-sided pressure was found in 37 of 44 patients (84%). The intraobserver and interobserver reproducibility

Discussion

The results of the present study are as follows: (1) overall in patients with OSAS, RV longitudinal strain and 3-D RVEF decreased and volumes increased in parallel with changes in segmental dyssynchrony in the presence and absence of PH; (2) RV dyssynchrony and 3-D RVEF had a greater association with OSAS severity compared with other echocardiographic indices of RV dysfunction; and (3) CPAP therapy tended to restore the uniformity of RV wall contraction with reduction of RV volumes.

Conclusions

Early impairment of RV mechanics in patients with isolated OSAS suggests that it is a response to overload caused by this disease independently of confounders. STE-determined RV dyssynchrony and 3-D volumes were the parameters most closely related with OSAS severity and ventricular subclinical dysfunction. CPAP therapy might prevent the progression of RV abnormalities and reverse these changes before severe structural alterations occur.

Disclosures

The authors have no conflicts of interest to disclose.

References (43)

  • A.J. Teske et al.

    Echocardiographic assessment of regional right ventricular function: a head-to-head comparison between 2-dimensional and tissue Doppler-derived strain analysis

    J Am Soc Echocardiogr

    (2008)
  • A. Vitarelli et al.

    Right ventricular function in acute pulmonary embolism: a combined assessment by three-dimensional and speckle tracking echocardiography

    J Am Soc Echocardiogr

    (2014)
  • A.P. Kalogeropoulos et al.

    Evaluation of right intraventricular dyssynchrony by two-dimensional strain echocardiography in patients with pulmonary arterial hypertension

    J Am Soc Echocardiogr

    (2008)
  • A. Romero-Corral et al.

    Decreased right and left ventricular myocardial performance in obstructive sleep apnea

    Chest

    (2007)
  • B. Shivalkar et al.

    Obstructive sleep apnea syndrome: more insights on structural and functional cardiac alterations, and the effects of treatment with continuous positive airway pressure

    J Am Coll Cardiol

    (2006)
  • D. Sajkov et al.

    Obstructive sleep apnea and pulmonary hypertension

    Prog Cardiovasc Dis

    (2009)
  • F. Chung et al.

    Serum bicarbonate level improves specificity of STOP-Bang screening for obstructive sleep apnea

    Chest

    (2013)
  • N. Kawata et al.

    Daytime hypercapnia in obstructive sleep apnea syndrome

    Chest

    (2007)
  • N. Risum et al.

    Variability of global left ventricular deformation analysis using vendor dependent and independent two-dimensional speckle-tracking software in adults

    J Am Soc Echocardiogr

    (2012)
  • K. Yamanaka Funabiki et al.

    Single beat determination of regional myocardial strain measurements in patients with atrial fibrillation

    J Am Soc Echocardiogr

    (2006)
  • Sleep-related breathing disorders in adults: recommendations for syndrome definition and measurement techniques in clinical research. The report of an American Academy of Sleep Medicine Task Force

    Sleep

    (1999)
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