Efficacy of sotalol in controlling reentrant supraventricular tachycardias.

Sotalol is unique among beta-blocking agents having significant Class III antiarrhythmic action. In a series of 22 patients with Wolff-Parkinson-White (WPW) syndrome and seven patients with atrioventricular nodal reentry tachycardia (AVNRT) resistant to multiple drugs, sotalol was studied by acute electrophysiologic means, as well as by long-term clinical follow-up ranging from 1 to 47 months. Sustained reciprocating tachycardia was rendered noninducible in 13 of 18 patients with WPW and in 5 of 6 with AVNRT. Long-term control of symptomatic tachycardia was achieved in 77% of patients with WPW and in 57% of patients with resistant AVNRT. Side effects were those associated with beta blockade. Two patients developed ventricular irritability associated with excessive QT prolongation.