Carvedilol, a heart failure drug used for adults, may not significantly help children and adolescents, according to a report published in The Journal of the American Medical Association (JAMA), September 12 issue.

The authors explain “Heart failure due to systemic ventricular dysfunction is a significant medical problem for children and represents the reason for at least 50 percent of pediatric referrals for heart transplantation. To date, there have been no large randomized controlled trials of any medication in children and adolescents with chronic heart failure. Treatment recommendations in children and adolescents with heart failure are extrapolated from the results of clinical trials conducted in adults, which may be problematic.”

Robert E. Shaddy, M.D., Children’s Hospital of Philadelphia and the University of Pennsylvania, and team looked at the effects of carvedilol, a beta-clocker, on 161 adolescents and children with heart failure. As well as receiving treatment with conventional medications for heart failure, the children were split into two groups, one received carvedilol while the other received a placebo – both for a period of 8 months. The carvedilol dosage depended on the weight of each child.

The scientists report that they saw no statistically significant difference between the two groups with regard to improvements or deteriorations during the course of the study.

— Of the 54 who received a placebo:
56% improved, 30% got worse, and 15% remained unchanged.

— Of the 103 who received carvedilol
56% improved, 24% got worse and 19% remained unchanged.

The authors wrote “This study did not detect a treatment effect of carvedilol on the primary composite end point of clinical heart failure outcomes. It is possible that children and adolescents with heart failure do not receive benefit from carvedilol; this would represent the first heart failure population not to show benefit with beta-blockade and is inconsistent with the many small studies supporting the benefit of beta-blockade in this patient population to date. It is unclear why carvedilol would be beneficial in adults with heart failure but not in children and adolescents. … given the lower than expected event rates, the trial may have been underpowered. There may be a differential effect of carvedilol in children and adolescents based on ventricular morphology.”

“Carvedilol for Children and Adolescents With Heart Failure – A Randomized Controlled Trial”
Robert E. Shaddy, MD; Mark M. Boucek, MD; Daphne T. Hsu, MD; Robert J. Boucek, MD; Charles E. Canter, MD; Lynn Mahony, MD; Robert D. Ross, MD; Elfriede Pahl, MD; Elizabeth D. Blume, MD; Debra A. Dodd, MD; David N. Rosenthal, MD; Jeri Burr, BS, RNC, CCRC; Bernie LaSalle, BS; Richard Holubkov, PhD; Mary Ann Lukas, MD; Lloyd Y. Tani, MD; For the Pediatric Carvedilol Study Group
JAMA. 2007;298:1171-1179.
Click here to view abstract online

Editorial:
“The Importance of Randomized Controlled Trials in Pediatric Cardiology”
Samuel S. Gidding, MD
JAMA. 2007;298:1214-1216.
Click here to view first 150 words online

Written by: Christian Nordqvist