Role of Cardiac Resynchronization in End-Stage Heart Failure Patients Requiring Inotrope Therapy

Abstract

Background Outcomes among inotrope-treated heart failure (HF) patients receiving cardiac resynchronization therapy (CRT) have not been well characterized, particularly in those requiring intravenous inotropes at the time of implant. Methods We analyzed 759 consecutive CRT-defibrillator recipients who were categorized as never on inotropes (NI; n = 585), weaned from inotropes before implant (PI; n = 124), or on inotropes at implant (II; n = 50). Survival free from heart transplant or ventricular assist device and overall survival were compared using the Social Security Death Index. A patient cohort who underwent unsuccessful CRT implantation and received a standard defibrillator (SD; n = 94) comprised a comparison group. Propensity score analysis was used to control for intergroup baseline differences. Results Compared with the other cohorts, II patients had more comorbidities. Both survival endpoints differed significantly ( P < .001) among the 4 cohorts; II patients demonstrated shorter survival than NI patients, with the PI and SD groups having intermediate survival. After adjusting for propensity scores, overall differences and patterns in survival endpoints persisted ( P < .01), but the only statistically significant pairwise difference was overall survival between the NI and II groups at 12 months (hazard ratio 2.95, 95% confidence interval 1.05-8.35). CRT recipients ever on inotropes (PI and II) and SD patients ever requiring inotropes (n = 17) experienced similar survival endpoints. Among II patients, predictors of hospital discharge free from inotropes after CRT included male gender, older age, and ability to tolerate β-blockade. Conclusions Inotrope-dependent HF patients show significantly worse survival despite CRT than inotrope-naïve patients, in part because of more comorbid conditions at baseline. CRT may not provide a survival advantage over a standard defibrillator among patients who have received inotropes before CRT. Weaning from inotropes and initiating neurohormonal antagonists before CRT should be an important goal among inotrope-dependent HF patients.