SAN FRANCISCO, CA—At ACC.13, the American College of Cardiology’s 62nd Annual Scientific Session, study authors presented that carvedilol compared to metoprolol was associated with a significant reduction in heart failure hospitalizations, death, and ventricular arrhythmias.

Optimal pharmacologic therapy is considered a prerequisite to consideration for cardiac resynchronization therapy (CRT),” stated Martin Huth Ruwald, MD, from University of Rochester Medical Center, Rochester, NY. Currently, metoprolol and carvedilol are the beta-blockers most often used in the management of patients with heart failure (HF). 

Dr. Ruwald and colleagues conducted a study to compare the effects of carvedilol and metoprolol in patients with HF receiving cardiac resynchronization therapy – defibrillation (CRT-D) or implantable cardioverter-defibrillator (ICD) therapy in The Multicenter Automatic Defibrillator Implantation Trial – Cardiac Resynchronization Therapy (MADIT-CRT) Trial. MADIT-CRT is the largest randomized NYHA Class I/III CRT-D that showed early intervention with CRT reduced the relative risk of all-cause mortality or first heart failure event by 57% when compared to ICD therapy (P<0.001).

The team used multivariate time-dependent Cox proportional hazard regression analyses to compare all patients receiving carvedilol or metoprolol (n=1,515) on the endpoints of hospitalizations for heart failure or death and ventricular arrhythmias.

Results showed that hospitalization for heart failure or death occurred in 30% of metoprolol patients and in 23% of carvedilol patients.  Treatment with carvedilol was associated with a 49% decreased risk of hospitalization for heart failure or death when compared to metoprolol (HR 0.7, CI 0.57-0.87; P=0.001). The risk reduction was further attenuated in the sub-group of CRT-D patients (HR 0.62, CI 0.46-0.83; P=0.001) and CRT-D patients with left bundle branch block (HR 0.51, CI 0.35-0.76; P<0.001).

Ventricular arrhythmias occurred in 26% of metoprolol patients and in 22% of carvedilol (HR 0.80, CI 0.63-1.00; P=0.050). A dose-dependent relationship with decreasing risk of hospitalization for heart failure or death was linked to carvedilol but not to metoprolol.

Dr. Ruwald also concluded that carvedilol proved a “pronounced beneficial and synergistic effect in patients with CRT-D and left bundle branch block.”