Abstract 13471: Implantable Defibrillators Improve Survival in Mildly Symptomatic Heart Failure Patients Receiving Cardiac Resynchronization Therapy: Analysis of the 5-Year Follow-Up of REVERSE
INTRODUCTION: Cardiac resynchronization therapy (CRT) improves functional status and reduces heart failure (HF) hospitalizations. Multicenter studies with long term follow-up have demonstrated a mortality benefit with either CRT pacemakers (CRT-P) or defibrillators (CRT-D). However, there is a paucity of data directly comparing long term outcomes with these 2 types of devices. Accordingly, results from the 5 year follow-up of REVERSE were analyzed to compare all-cause mortality between CRT-P and CRT-D in mild HF.
METHODS and RESULTS: REVERSE was a double-blinded randomized 2:1 (CRT-ON vs CRT-OFF) study of patients with QRS prolongation (> 120 msec), systolic dysfunction (Ejection fraction < 40%) and mild HF (NYHA I-II). CRT-ON patients received CRT-P (n=74, 17.8%) or CRT-D (n=345, 82.3%) per current guidelines and physician discretion. Kaplan-Meier analysis with log rank statistic and multivariable Cox regression analyses were performed. CRT-D patients had larger hearts (LVESVi), lower ejection fraction, a lower percentage with LBBB, and were more likely to have ischemic cardiomyopathy compared to CRT-P. At 5 years, mortality rate was lower with CRT-D patients (n=40, 12.2%) compared with CRT-P (n=13, 19.2%). Over a mean follow up of 4.6+1.1 years, the hazard ratio was 0.66 ([95% CI 0.35-1.23]; p=0.18, Figure). Multivariable analysis showed improved survival with CRT-D (0.35 [0.17-0.69]; p=0.003) after adjusting for age, gender, ischemic etiology, EF, QRS duration and morphology, LVESVi, NYHA class, and diabetes.
CONCLUSIONS: The addition of defibrillator therapy to CRT in mild HF markedly reduced mortality compared with CRT pacing alone.
- © 2012 by American Heart Association, Inc.