Intravenous amiodarone significantly reduced median time to success in a dose-dependent manner (28.2, 2.6, and 2.1 hours for low, medium, and high doses, respectively; P=0.028).
RCT (n=61)
Double-blind
Randomized to 1 of 3 dosing regimens
Yes
Does the dose of intravenous amiodarone affect the time to success in children with incessant tachyarrhythmias?
In children with incessant tachyarrhythmias, higher doses of intravenous amiodarone significantly reduce the time to success but are associated with frequent, dose-related adverse events.
Absolute Event Rate: 2.1% vs 28.2%
p-value: p=0.028
BACKGROUND: Intravenous (IV) amiodarone has proven efficacy in adults. However, its use in children is based on limited retrospective data. METHODS AND RESULTS: A double-blind, randomized, multicenter, dose-response study of the safety and efficacy of IV amiodarone was conducted in 61 children (30 days to 14.9 years; median, 1.6 years). Children with incessant tachyarrhythmias (supraventricular arrhythmias n=26, junctional ectopic tachycardia JET, n=31, or ventricular arrhythmias n=4) were randomized to 1 of 3 dosing regimens (low, medium, or high: load plus 47-hour maintenance) with up to 5 open-label rescue doses. The primary efficacy end point was time to success. Of 229 patients screened, 61 were enrolled during 13 months by 27 of 48 centers in 7 countries. Median time to success was significantly related to dose (28.2, 2.6, and 2.1 hours for the low-, medium-, and high-dose groups, respectively; P=0.028). There was no significant association with dose for any arrhythmia subgroup, including JET, but the subgroups were too small for an accurate assessment. Adverse events (AEs) were common (87%), leading to withdrawal of 10 patients. There were 5 deaths in the 30-day follow-up period (2 possibly related to the study drug). Dose-related AEs included hypotension (36%), vomiting (20%), bradycardia (20%), atrioventricular block (15%) and nausea (10%). CONCLUSIONS: In children, the overall efficacy of IV amiodarone, as measured by time to success, was dose related but not significantly for any arrhythmia subgroup. AEs were common and appeared to be dose related. Although efficacious for critically ill patients, the dose-related risks of IV amiodarone should be taken into account when treating children with incessant arrhythmias. Prospective, placebo-controlled trials would be helpful in assessing antiarrhythmic drug efficacy in children, because their results may differ from retrospective series and adult studies.
Saul et al. (Tue,) conducted a rct in Incessant tachyarrhythmias (n=61). Intravenous amiodarone vs. Low-dose amiodarone was evaluated on Time to success (p=0.028). Intravenous amiodarone significantly reduced median time to success in a dose-dependent manner (28.2, 2.6, and 2.1 hours for low, medium, and high doses, respectively; P=0.028).