Cardiac Resynchronization Therapy in continuous flow Left Ventricular Assist Device Recipients: A Systematic Review and Meta-analysis from ELECTRAM Investigators.

Dhanunjaya Lakkireddy

doi:10.4022/jafib.2441

Abstract

Whether cardiac resynchronization therapy (CRT) continues to augment left ventricular remodeling in patients with the continuous-flow left ventricular assist device (cf-LVAD) remains unclear. We performed a systematic review and meta-analysis of all clinical studies examining the role of continued CRT in end-stage heart failure patients with cf-LVAD reporting all-cause mortality, ventricular arrhythmias, and ICD shocks. Mantel-Haenszel risk ratio (RR) random-effects model was used to summarize data. Eight studies (7 retrospective and 1 randomized) with a total of 1,208 unique patients met inclusion criteria. There was no difference in all-cause mortality (RR 1.08, 95% CI 0.86 - 1.35, p = 0.51, I2=0%), all-cause hospitalization (RR 1.01, 95% CI 0.76-1.34, p = 0.95, I2=11%), ventricular arrhythmias (RR 1.08, 95% CI 0.83 - 1.39, p = 0.58, I2 =50%) and ICD shocks (RR 0.87, 95% CI 0.57 - 1.33, p = 0.52, I2 =65%) comparing CRT versus non-CRT. Subgroup analysis demonstrated significant reduction in ventricular arrhythmias (RR 0.76, 95% CI 0.64 - 0.90, p = 0.001) and ICD shocks (RR 0.65, 95% CI 0.44 - 0.97, p = 0.04) in "CRT on" group versus "CRT off" group. CRT was not associated with a reduction in all-cause mortality or increased risk of ventricular arrhythmias and ICD shocks compared to non-CRT in cf-LVAD patients. It remains to be determined which subgroup of cf-LVAD patients benefit from CRT. The findings of our study are intriguing, and therefore, larger studies in a randomized prospective manner should be undertaken to address this specifically.

Highlights

Whether cardiac resynchronization therapy (CRT) continues to augment left ventricular remodeling in patients with the continuous-flow left ventricular assist device remains unclear
When comparing “CRT on” vs.“CRT off ”10,11, “CRT on” group was associated with a lower incidence of ventricular arrhythmias as compared to “CRT off ”group in continuous-flow left ventricular assist device (cf-Left ventricular assist device (LVAD)) patients (57.9% vs. 75.7%, risk ratio (RR) 0.76, 95% CI 0.64 – 0.90, p = 0.001)
The incidence of implantable cardioverter-defibrillator (ICD) shocks did not differ between CRT and non-CRT group in cf-LVAD patients (35.86% vs 33.58%, RR 0.87, 95% CI 0.57 – 1.33, p = 0.52)

Summary

Introduction

Whether cardiac resynchronization therapy (CRT) continues to augment left ventricular remodeling in patients with the continuous-flow left ventricular assist device (cf-LVAD) remains unclear. Studies have shown that cardiac resynchronization therapy (CRT) improves the quality of life, decreases heart failure hospitalization, reduces left ventricular dimensions and overall mortality in patients left ventricular ejection fraction (LVEF) ≤ 35%, NYHA functional class I-III and wide QRS in addition to guideline-directed medical therapy[2,3,4]. Left ventricular assist device (LVAD) has been a viable alternative and has been increasingly used as destination therapy (DT), bridge to transplant (BT), and bridge to recovery in end-stage www.jafib.com. The Newcastle Ottawa Risk bias assessment tool was used to appraise the quality of non-randomized studies (Supplement Table[2]). The Cochrane – Risk bias assessment tool was used to appraise the quality of a randomized controlled trial (Supplement Table[3])

Results

Discussion

Conclusion