Researchers Identity New Risk Factors for Heart Muscle Disease in Children
Miller School of Medicine researchers and their collaborators have identified important risk factors for death and transplantation in children with dilated cardiomyopathy (heart muscle disease), in findings published online July 25 in the journal Circulation. The disease affects 1 in 100,000 children, and nearly 40 percent with symptomatic dilated cardiomyopathy receive a transplant or fail medical management and die within two years of diagnosis.
Using these newly identified risk factors, physicians may be better able to identify children who will benefit from life-saving cardiac transplantation surgery. The current criteria for receiving a transplant sometimes miss children who could benefit.
“The risk factors we identified included echocardiographic evidence of more severe disease, increased age and dilation of the left ventricle,” said Steven E. Lipshultz, M.D., professor and chair of pediatrics at the Miller School, senior author of the study and principal investigator of the Pediatric Cardiomyopathy Registry. “Two additional risk factors really stood out from the rest: impaired growth in height, and dilated cardiomyopathy that had already progressed to congestive heart failure.
“As pediatric cardiologists, these findings tell us if you have a child who is really sick with congestive heart failure, and on top of everything else that child is also really short, they should get listed for a heart transplant right away.”
The study, titled “Competing Risks for Death and Cardiac Transplantation in Children with Dilated Cardiomyopathy,” mined data from the nationwide Pediatric Cardiomyopathy Registry, based at the Miller School. From 1990 to 2007 the registry enrolled 1,731 children (18 years of age or younger) diagnosed with pediatric dilated cardiomyopathy. The registry was established by the National Heart, Lung, and Blood Institute of the National Institutes of Health to collect and organize data on the condition, which will help determine the causes of the disease and lead to new and better treatments.
Jorge A. Alvarez, M.D., Ph.D., served as the first author of the study while a student in the Miller School’s M.D./Ph.D. program. His research, which resulted from his Ph.D. dissertation project, used a novel statistical approach — competing risks analysis. The findings should influence the way pediatric cardiologists decide who should be listed for a heart transplant and ultimately save the lives of many children with cardiomyopathy. Dr. Alvarez’s mentors for the project were James D. Wilkinson, M.D., M.P.H., professor of pediatrics and epidemiology and public health and one of the study’s authors, and Dr. Lipshultz.
“Jorge performed this research in what is one of only a handful of M.D./Ph.D. programs in the country that offers a track in epidemiology,” said Dr. Wilkinson. “It is a testament to his hard work and discipline that he was able to publish his findings in such a prestigious journal of the American Heart Association.”
Dr. Alvarez is currently a first-year resident in internal medicine at Brown University/Rhode Island Hospital.