Safety and efficacy of short- and long-term verapamil therapy in children with tachycardia

Abstract

Six children aged 3 months to 11 years were treated with verapamil because of resistant symptomatic supraventricular tachycardia or complications of conventional therapy. Two of the three patients with congenital heart disease were in the postoperative state. The other three had no gross cardiac anomalies. Two patients had supraventricular tachycardia with Wolff-Parkinson-White syndrome, three had ectopic supraventricular tachycardia and one had atrial flutter. Intravenous verapamil was given in a dose of 0.15 to 0.25 mg/kg body weight to four patients, three of whom had successful conversion to sinus rhythm. One patient was given oral verapamil only. Treatment failed in the patient with atrial flutter. Five patients were maintained on oral verapamil therapy. Of these, one patient died of postoperative complications while receiving verapamil, and the remaining four have continued oral verapamil therapy for 1 to 3 1 2 years . The dose is 80 mg every 6 or 8 hours depending on response. Two of the latter four patients have ectopic supraventricular tachycardia that recurs when therapy is stopped. Of the two patients with Wolff-Parkinson-White syndrome, one has had no recurrence of supraventricular tachycardia and the other has had a decrease in both the duration of attacks and their number (from one to two per week to one to two per month). There have been no adverse effects with long-term drug administration. None of the five patients who received intravenous verapamil showed any untoward effects during its administration. This experience indicates that verapamil, which has not been used extensively in children, is an effective and safe antiarrhythmic drug capable of controlling both ectopic and reentrant supraventricular tachycardia when conventional methods fail. The presence of underlying congenital heart disease should not be a contraindication to its use.