Conversion of atrial fibrillation and flutter by propranolol.

Abstract
Three cases of atrial fibrillation and 2 of atrial flutter, all of recent origin, were converted to sinus rhythm by propranolol. Digitalis, quinidine, and DC countershock were completely ineffective in 3 of the 5 cases. Propanolol may offer a safe and effective approach to this problem.