Prospective single-arm protocol of carvedilol in children with ventricular dysfunction

Abstract

The objective of this study was to evaluate the safety and efficacy of carvedilol in pediatric patients with stable moderate heart failure. We performed a single-arm prospective drug trial at three academic medical centers and the results were compared to historical controls. Patients were 3 months to 17 years old with an ejection fraction <40% in the systemic ventricle for at least 3 months on maximal medical therapy including ACE inhibitors. Treated patients were started on 0.1 mg/kg/day and uptitrated to 0.8 mg/kg/day or the maximal tolerated dose. Echocardiographic parameters of function were prospectively measured at entry and at 6 months. Two composite endpoints were recorded: severe decline in status and significant clinical change. Adverse events were reviewed by a safety committee. Data were also collected from untreated controls with dilated cardiomyopathy meeting entry criteria, assessed over a similar time frame. Twenty patients [12 dilated cardiomyopathy (DCM) and 8 congenital] with a median age of 8.4 years (range, 8 months to 17.8 years) were treated with carvedilol. Three patients discontinued the drug during the study. At entry, there was no statistical difference in age, weight, or ejection fraction between the treated group and controls. The ejection fraction of the treated DCM group improved significantly from entry to 6 months (median, 31 to 40%, p = 0.04), with no significant change in ejection fraction in the control group [median, 29 to 27%, p = not significant (NS)]. The median increase in ejection fraction was larger for the treated DCM group than for the untreated DCM controls (7 vs 0%, p = 0.05). By Kaplan-Meier analysis, time to death or transplant tended to be longer in treated patients (p = 0.07). The difference in the proportion of patients with severe decline in status or significant clinical change in the treated group was not significant compared to the controls (5 vs 12%, p = NS). We conclude that in this prospective protocol of pediatric patients, the use of adjunct carvedilol in the DCM group improved ejection fraction compared to untreated controls and trended toward delaying time to transplant or death.