Successful management of atrial flutter in a newborn with verapamil

Abstract

Summary:Verapamil has become a popular antiarrhythmic drug for the acute management of supraventricular tachycardia in infants and children. A fullterm, 1 -hour-old infant presented with supraventricular tachycardia and hypotension that did not respond to vagal maneuvers and direct current cardioversion. After intravenous verapamil, the heart rate slowed and the underlying rhythm was atrial flutter.Key words: newborn infants, verapamil, supraventricular tachycardia Case ReportThis I-hour-old, 3.31 kg, full-term male infant was born by vaginal delivery to an 18-year-old mother following a pregnancy complicated by pre-eclampsia. Fetal monitoring revealed a fast heart rate. Because of preeclampsia and fetal tachycardia, labor was induced. Apgars were 6 and 8 at 1 min and 5 min, respectively, and the initial heart rate was 280 beatdmin. The infant's perfusion was poor. Blood pressure was 50/42 mmHg and failed to improve after plasmanate infusion, Heart exam was normal, but all peripheral pulses were equally weak. No hepatosplenomegaly was present. An electrocardiographic rhythm strip (Fig. 1 A) demonstrated supraventricular tachycardia which did not respond to vagal maneuvers. Direct current cardioversion was attempted three times without conversion. Three minutes after intravenous verapamil (0.075 mg/kg), the heart rate fell to 160 beats/min and atrial flutter was seen to be the underlying rhythm (Fig. IB). A second dose of verapamil (total dosage 0.15 mg/kg) resulted in sinus rhythm (Fig. 1C). The blood pressure rose to 62/42 mmHg and peripheral perfusion improved. A 12-lead electrocardiogram during sinus rhythm showed no evidence of pre-excitation. The chest radiogram was normal. Two-dimensional echocardiography showed no structural abnormalities. The infant was started on digoxin for maintenance therapy but another dose of verapamil (0.075 mg/kg) for recurrent supraventricular tachycardia was necessary 24 h after digitalization. This resulted in sinus rhythm. The infant was discharged at age 8 days in sinus rhythm with a digoxin blood level of 2.2 ng/ml. At 1 month, he was readmitted in shock as a result of recurrent supraventricular tachycardia (300 beatdmin). On admission his blood pressure was 45/27 mmHg . Intravenous verapamil (0.15 mg/kg) slowed the heart rate to 150 beats/min and atrial flutter with variable block was again noted. The blood pressure increased to 70/40 mmHg. During hospitalization, he had several nonsustained (duration of less than 20 min) episodes of atrial flutter with varying degrees of atrioventricular block. He was started on oral propranolol which prevented any recurrence of supraventricular tachycardia. The infant was discharged on digoxin (level 1.4 ng/ml) and propranolol. At follow-up (age 3 months) he was still in sinus rhythm.

Management of intractable supraventricular tachycardia unresponsive to primary therapy with Verapamil in a neonatal case

“…[4][5][6] Verapamil is a class IV anti arrhythmic agent that acts as a selective inhibitor of myocardial calcium channels. It is used for the acute termination of SVT when first therapeutic options fail with a strong effectiveness in over 90% of children, although it is unlikely to be indicated in infants due to the risk for circulatory hypo perfusion 2,4,7 Many articles have recommended Verapamil for infants as a second-line agent for unresponsive-to-first-line therapies for SVT. [8][9][10] Here, we report a case of an intractable Supraventricular tachycardia successfully managed with intravenous Verapamil in a newborn unresponsive to multiple first-line therapies.…”