Randomized double blind trial comparing sotalol and propranolol in chronic ventricular arrhythmia.

Sotalol is a beta-blocker which also prolongs repolarization. Its relative efficacy towards suppressing chronic ventricular arrhythmia was tested by comparison with propranolol. This double blind parallel comparison study involved 30 patients with or without coronary artery disease who had chronic symptomatic ventricular arrhythmia and more than an average of 30 premature ventricular complexes (PVCs) per hour. After the placebo baseline period patients received four weeks of active treatment with sotalol or propranolol. Responders were patients who had 75% or more reduction of PVCs during 24 h Holter monitoring. One patient in each treatment group had intolerable side effects on a low dose of the drug and were withdrawn. Side effects were present more frequently in the propranolol group compared with sotalol. Proarrhythmic effects were present in one patient on sotalol. There was no significant difference in suppression of ventricular extrasystoles (sotalol 65%, propranolol 44%), with reduction in ventricular couplets being 99% for sotalol and 49% for propranolol. There was a significant increase in QTc in patients on sotalol. Therefore, sotalol is a well tolerated drug and may be preferable to propranolol for control of chronic ventricular arrhythmia.