Objective: The purpose of this study was to analyze the efficacy and safety of intravenous amiodarone in young patients with critical, drug-resistant arrhythmias.
Background: Intravenous amiodarone has been investigated in adults since the early 1980s. Experience with the drug in young patients is limited. A larger pediatric study group was necessary to provide responsible guidelines for the drug's use before its market release.
Methods: Eight centers obtained institutional approval of a standardized protocol. Other centers were approved on a compassionate use basis after contacting the primary investigator (J.C.P).
Results: Forty patients were enrolled. Standard management in all failed. Many patients had early postoperative tachyarrhythmias (25 of 40), with early successful treatment in 21 (84%) of 25. Twelve patients had ventricular tachyarrhythmias: seven had successful therapy, and six died, none related to the drug. Eleven patients had atrial tachyarrhythmias: 10 of 11 had immediate success, but 3 later died. Fourteen patients had junctional ectopic tachycardia, which was treated with success (sinus rhythm or slowing, allowing pacing) in 13 of 14, with no deaths. Three other patients had supraventricular tachycardias, with success in two and no deaths. The average loading dose was 6.3 mg/kg body weight, and 50% of patients required a continuous infusion. Four patients had mild hypotension during the amiodarone bolus. One postoperative patient experienced bradycardia requiring temporary pacing. There were no proarrhythmic effects. Deaths (9 [23%] of 40) were not attributed to amiodarone.
Conclusions: Intravenous amiodarone is safe and effective in most young patients with critical tachyarrhythmia. Intravenous amiodarone can be lifesaving, particularly for postoperative junctional ectopic tachycardia, when standard therapy is ineffective.