Dose-Response Effect of Propafenone in Patients with Ventricular Arrhythmias

Abstract

Propafenone has electrophysiologic properties which permit its classification as a class I antiarrhythmic agent (agents in this class have characteristics similar to quinidine and procainamide). These properties were reviewed in many presentations at an international symposium (Hochrein et al. 1977). In animal studies, propafenone increased both the ventricular fibrillation threshold and the functional refractory period in the isolated guinea pig atrium. In Purkinje and myocardial fibres, the compound reduced mainly the rate of rise of the action potential (Bergmann and Bolte 1977). In human studies, propafenone induced a relatively uniform slowing of the conduction rate of all sections of the heart (Seipel et al. 1975) and the delay in the atrioventricular node was markedly dose-dependent (Keller et al. 1978). In initial clinical studies propafenone was found to be effective in ventricular and supraventricular arrhythmias (Ivancic and Goldner 1977; Rutsch 1978; Wieser et al. 1979).