Effectiveness and safety of intravenous amiodarone in drug-resistant tachyarrhythmias of children

Experience with pediatric use of intravenous amiodarone is limited. In this study, our experiences with intravenous amiodarone in children with acute life-threatening or chronic tachyarrhythmias are reviewed. Twelve patients, with a mean age of 3.4 +/- 3.1 years, range 9 months-10 years (two with incessant ventricular tachycardia, one with ectopic atrial tachycardia, two with atrioventricular re-entrant tachycardia (three episodes), four with postoperative or congenital junctional ectopic tachycardia, two with bradycardia-tachycardia syndrome, one with atrial tachycardia) were treated with intravenous amiodarone during 13 tachycardia episodes. Left ventricular systolic functions were depressed in six patients. In 11 patients, a median of two drugs (range one-four), including adenosine infusion and in five cases direct current cardioversion were tried without success prior to intravenous amiodarone. The loading dose of amiodarone was 5 mg/kg in all episodes, infused over 1 h. Maintenance infusion was required in 12 episodes. In 10 episodes (77%), amiodarone was considered effective, in one (7.6%) partially effective (junctional ectopic tachycardia) and in two (15.4%) ineffective (sick sinus syndrome, atrial tachycardia). Therapeutic effect was obtained in a median period of 30 h (range 1-103 h). The mean effective maintenance dose was 10 +/- 4.7 micrograms/kg per min (range 5-15 micrograms/kg per min). In one patient, mild hypotension, and in three patients cellulitis occurred, but none of them necessitated termination of treatment. Intravenous amiodarone is found to be an effective and safe antiarrhythmic agent for children with acute life-threatening and chronic tachyarrhythmias and depressed left ventricular systolic functions.