Objectives: This study sought to compare the effects of metoprolol and carvedilol in the MADIT-CRT (Multicenter Automatic Defibrillator Implantation Trial With Cardiac Resynchronization Therapy) study. Background: The impact of beta-blockers in heart failure (HF) patients with devices is uninvestigated. Methods: All patients receiving either metoprolol or carvedilol in the MADIT-CRT study were identified and compared. Time-dependent Cox proportional hazard regression analyses were performed to assess differences in hospitalization for HF or death and ventricular arrhythmias. Results: Hospitalization for HF or death occurred in 30% of the patients on metoprolol and in 23% on carvedilol. Treatment with carvedilol was associated with a significantly decreased risk of hospitalization for HF or death when compared with metoprolol (hazard ratio [HR]: 0.70, [95% confidence interval (CI): 0.57 to 0.87], p = 0.001). This reduction in risk was further attenuated in the subgroup of cardiac resynchronization therapy with implantable cardioverter-defibrillator (CRT-D) patients (HR: 0.61 [95% CI: 0.46 to 0.82], p = 0.001) and CRT-D patients with left bundle branch block (LBBB) (HR: 0.51 [95% CI: 0.35 to 0.76], p < 0.001). Ventricular arrhythmias occurred in 26% and in 22%, respectively, of the patients receiving metoprolol or carvedilol (HR: 0.80 [95% CI: 0.63 to 1.00], p = 0.050). General use of beta-blockers and adherence in this study was high, and a clear dose-dependent relationship was found in carvedilol, but not in metoprolol. Conclusions: In HF patients in New York Heart Association functional class I and II and with wide QRS complexes, carvedilol was associated with a 30% reduction in hospitalizations for HF or death when compared with metoprolol. A novel beneficial and synergistic effect of carvedilol was seen in patients with CRT-D and LBBB. Furthermore, we found a pronounced dose-dependent relationship in carvedilol, but not in metoprolol. (MADIT-CRT: Multicenter Automatic Defibrillator Implantation Trial With Cardiac Resynchronization Therapy; NCT00180271) © 2013 American College of Cardiology Foundation.
Ruwald, M. H., Ruwald, A. C. H., Jons, C., Alexis, J., McNitt, S., Zareba, W., & Moss, A. J. (2013). Effect of metoprolol versus carvedilol on outcomes in MADIT-CRT (Multicenter Automatic Defibrillator Implantation Trial with Cardiac Resynchronization Therapy). Journal of the American College of Cardiology, 61(14), 1518–1526. https://doi.org/10.1016/j.jacc.2013.01.020