Antiarrhythmic effectiveness of alprenolol, a new beta adrenergic receptor blocking agent

Abstract

Summary A double blind placebo-controlled (cross-over) study of the antiarrhythmic efficacy of alprenolol, a new beta receptor blocking agent, was carried out in patients with supraventricular and ventricular arrhythmias. Alprenolol was found to produce a statistically significant reduction in the incidence of ventricular premature contractions whereas no significant reduction in the incidence of ventricular premature contractions whereas no significant reduction in the incidence of premature contractions was observed with placebo therapy. A statistically significant reduction in ventricular rate also was observed following alprenolol therapy in patients with supraventricular tachyarrhythmias. No significant effect on ventricular rate was observed following administration of saline. A slight, but statistically significant, reduction in systolic blood pressure was observed during alprenolol therapy but not during placebo therapy. No change was observed in diastolic blood pressure with either solution. In 1 patient during alphrenolol infusion systolic and diastolic blood pressure fell to such a degree that the infusion was interrupted. The hypotension was transient, returning to control level without any therapy. Thus, the results of this controlled investigation indicate that alprenolol is an effective antiarrhythmic agent for the treatment of ventricular premature contractions and for the reduction of ventricular rate in patients with supraventricular arrhythmias, notably atrial fibrillation. No conclusion can be made regarding the effectiveness of alprenolol in nodal tachycardia since only 1 case was encountered and, in this instance, therapy was ineffective.