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 [nϭ26], junctional ectopic tachycardia [JET, nϭ31], or ventricular arrhythmias [nϭ4]) 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; Pϭ0.028). 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.

Antihypertensive medications are used extensively in children despite a paucity of randomized, placebo-controlled trials. This study was among the first randomized, controlled pediatric antihypertensive medication trials, in which the combination drug bisoprolol fumarate/hydrochlorothiazide (B/HT) was compared with placebo. The study comprised a 2-week single-blind placebo screening period, a 6-week double-blind dose titration period, a 4-week double-blind dose maintenance period, and a 2-week double-blind dose-tapering period. One hundred and forty subjects were enrolled to achieve 94 randomized subjects treated either with B/HT ( n=62) or placebo ( n=32). B/HT induced significant reductions compared with placebo for average sitting systolic blood pressure (SiSBP) (9.3 vs. 4.9 mmHg, P<0.05) and sitting diastolic blood pressure (SiDBP) (7.2 vs. 2.7 mmHg, P<0.05). The placebo-subtracted BP reductions were greater in younger children and those with more-severe baseline hypertension. The percentage of subjects with BP less than the 90th percentile at study completion was 45% for B/HT and 34% for placebo ( P=NS). Although the study demonstrated that B/HT reduced BP safely compared with placebo, the large placebo effect and failure of most subjects to achieve target BP control make it uncertain whether B/HT is appropriate first-line therapy for pediatric hypertension, particularly in adolescents with mild-to-moderate BP elevation.

A factorial design was applied in this multicenter, double-blind, placebo-controlled trial of the calcium-channel blocker verapamil and the ACE inhibitor enalapril to assess the hypotensive effects of the combination compared with monotherapy, to evaluate safety, and to determine the effects on quality of life (QOL) of both drugs, alone and in combination. The study consisted of a 3 x 2 factorial design wherein 186 men and women with a sitting diastolic blood pressure (BP) of between 95 mm Hg and 114 mm Hg, after a 4-week placebo washout, were randomized to one of six treatment groups for 4 weeks of active treatment. Monotherapy with both 240 mg verapamil and 10 mg enalapril reduced systolic and diastolic BP to a similar extent and significantly more than placebo. The 240 mg verapamil + 10 mg enalapril combination was additive for both systolic and diastolic blood pressure; 120 mg verapamil + 10 mg enalapril was additive for systolic BP only. The total number of adverse events reported was similar for all six treatment groups. QOL scores were unchanged from baseline and not different between treatment groups. The combination of 240 mg verapamil and 10 mg enalapril was significantly more effective at reducing BP than either drug alone; this additivity of effect was not linked to a higher rate of adverse experiences or to a deterioration in QOL. Thus, combination therapy at lower doses may offer an alternative treatment option to higher dose monotherapy.

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