The effect of sotalol on exercise-induced ventricular arrhythmias.
Sotalol is a non-selective beta-adrenergic blocking agent with class III antiarrhythmic properties. Our study was intended to assess the efficacy of sotalol on exercise-inducible arrhythmias by oral administration to out patients. Thirty patients with exercise-inducible arrhythmias (80% coronary artery disease, 20% congestive cardiomyopathy) were studied after two baseline bicycle ergometric stress tests performed in upright position. Twenty-five patients (including nine crossover cases of the lower dose protocol) were given sotalol in a daily dose of 320 mg (group 1) and 14 patients in a dose of 160 mg (group 2). After 2 and 8 weeks, respectively, group 1 showed a mean reduction of the total number of inducible ventricular premature beats (VPBs) of 50% (P = 0.0042) and 61% (P = 0.0107), respectively and a significantly improved Lown score (P = 0.0002 and 0.0006, respectively). A significant antiarrhythmic response was not demonstrable for group-2 patients. Because of inefficacy, nine patients were changed from group 2 to group 1. Reduction of arrhythmias on the higher dose was significant (P = 0.0147) in this group. There was the same significant reduction of the heart rate pressure product with the low and high dosage indicating that the beta-blocker effect is achieved with the lower dosage. We conclude that sotalol is a powerful drug for reducing the number and complexity of ventricular arrhythmias in a dose of 320 mg daily. As the beta-blocking effect in both groups was the same, we assume that the reduction of arrhythmias is mainly due to class III action.
Petzl
D H
DH
University of Vienna, Clinic of Cardiology, Austria.
Probst
P
P
Glogar
D
D
Schuster
E
E
D000293:Adolescent; D000328:Adult; D000368:Aged; D001145:Arrhythmias, Cardiac / Q000188:drug therapy*; D001794:Blood Pressure / Q000187:drug effects; D009202:Cardiomyopathies / Q000150:complications; D003327:Coronary Disease / Q000150:complications; D004305:Dose-Response Relationship, Drug; D004562:Electrocardiography; D005080:Exercise Test; D005260:Female; D006339:Heart Rate / Q000187:drug effects; D006801:Humans; D008297:Male; D008875:Middle Aged; D013015:Sotalol / Q000627:therapeutic use*
D013015:Sotalol