Comparison of acebutolol and propranolol for treatment of chronic ventricular arrhythmia: a placebo-controlled, double-blind, randomized crossover study.

Abstract

The effects on ventricular arrhythmia of acebutolol were compared with those of propranolol in 31 patients who averaged more than 30 ventricular premature complexes (VPCs) per hour during 72 hours of ambulatory ECG recording during a placebo-controlled baseline period. The study consisted of an initial 2- week placebo-controlled baseline period followed by two 6-week double-blind treatment periods consisting of incremental dose-titration, maintenance and dose-tapering schedules. The treatment during the double-blind period was randomized to either oral acebutolol or propranolol given three times daily. Twenty-four-hour am- bulatory ECGs and maximal (symptom-limited) treadmill exercise tests were performed after 1 and 5 weeks of treatment with either acebutolol (1587 397 mg/day) or propranolol (202 63 mg/day) in each patient. The effects of acebutolol and propranolol on the frequency and grade of ventricular arrhythmia during rest and ex- ercise were compared.