Long-term oral antiarrhythmic therapy with aprindine: effects on cardiac function and adverse effects.

The effects of long-term aprindine administration on cardiac function were clinically investigated in seven patients with supraventricular or ventricular arrhythmias associated with organic heart disease. Three patients had normal cardiac function and four had various degrees of cardiac dysfunction before treatment with aprindine. The drug was administered orally in doses of 25 to 75 mg daily (mean +/- SD, 54 +/- 14 mg/day). The duration of follow-up ranged from six to 23 months (mean +/- SD, 14 +/- 6 months). An antiarrhythmic effect was achieved in five cases. No worsening or newly acquired symptoms or signs of cardiac dysfunction were recognized. No significant changes in end-diastolic dimension or ejection fraction were observed echocardiographically. Results of this study suggest that aprindine, which has been reported to have a negative inotropic action, does not cause significant deterioration of cardiac function even when given as long-term antiarrhythmic therapy to patients with cardiac dysfunction.