[Sotalol in supraventricular tachycardia. Electrophysiologic measurements in Wolff-Parkinson-White syndrome and AV node re-entry tachycardia].

The electrophysiologic effects of sotalol were studied in 11 patients with Wolff-Parkinson-White syndrome and 9 patients with AV nodal reentrant tachycardia. Electrophysiologic studies were performed before and after intravenous infusion of 80 mg sotalol over a period of 5 minutes. Sotalol prolonged the effective refractory period of the right atrium and the right ventricle. Both AV node and accessory pathway conduction were depressed by sotalol in antegrade and retrograde directions. Induction of reentrant tachycardia was prevented in 6 of 18 patients. The rate of reentrant tachycardia decreased from 182 +/- 29/min to 153 +/- 14/min (p less than 0.01) and the ventricular rate during atrial fibrillation from 148 +/- 14/min to 112 +/- 12/min (p less than 0.05). Sotalol exhibited a depressant effect on all parts of the reentrant circuit: atrium, ventricle, AV node, and accessory pathway. Thus, sotalol is effective in the therapy of patients with recurrent supraventricular tachycardias.