Antiarrhythmic Effects of L-Penbutolol and DL-Propranolol

Comparison of the Effects of These Two Drugs on Conductivity and Excitability in Canine Heart in Vivo

抄録

The effects of l-penbutolol and dl-propranolol on A-V conduction, on excitability of ventricular muscle, and on ventricular tachycardia threshold in acute ischemia were compared, using anesthetized dogs
1. L-penbutolol (100μg/Kg) and dl-propranolol (100μg/Kg) prolonged A-V conduction and reduced excitability of ventricular muscle significantly. L-penbutolol less prolonged A-V conduction than dl-propranolol
2. Both l-penbutolol (50μg/Kg) and dl-propranolol (50μg/Kg) significantly prevented the lowering of ventricular tachycardia threshold in acute ischemia
These beta-blocking drugs are effective in the treatment of arrhythmia and l-penbutolol could be used safely, because of its weaker inhibition on A-V conduction