Treatment of supraventricular arrhythmias with intravenous and oral verapamil.

Verapamil or placebo was administered as a bolus infusion in a double-blind fashion to 24 patients with either atrial fibrillation or flutter and to ten patients with paroxysmal supraventricular tachycardia. Patients whose heart rate did not decrease below 100 beats/min were given a second dose. Of the 24 patients with atrial fibrillation or flutter, 11 received placebo first. Control heart rate and blood pressure were not modified by placebo; however, verapamil significantly reduced heart rate and systolic blood pressure in the 24 patients. Of the ten patients with paroxysmal supraventricular tachycardia, one reverted to sinus rhythm after administration of placebo. For the remaining nine, the heart rate was not modified by placebo but was significantly reduced by verapamil administration. Blood pressure was not modified by verapamil or placebo in these ten patients. Long-term oral verapamil treatment was maintained without interruption in 18 patients for a mean of 16 +/- 7.5 months, and 15 patients required concomitant therapy with other antiarrhythmic drugs for rhythm control. All patients reported symptomatic improvement, and the number of hospitalizations required for arrhythmia control decreased significantly. Verapamil is safe and effective for acute control of supraventricular arrhythmias. Long-term oral administration, alone or with other antiarrhythmic drugs, is an important contribution to the management of recurrent supraventricular arrhythmias.

RCT Entities:   Population Interventions Outcomes