Screening Recommended for Familial Heart Disease
09/22/99 Portland, Ore.
OHSU team's genetic linkage project finds family links to heart condition.
A new study recommends that patients with idiopathic dilated cardiomyopathy (IDC), a heart muscle disease of unknown cause that results in cardiac enlargement, should have family members screened for the same condition. The disease commonly results in heart failure and/or sudden death.
The study, published in the September issue of the Journal of the American College of Cardiology, builds on previous work that indicated a genetic, or familial basis is likely in one-third to one-half of patients diagnosed with IDC.
The study examined four families with familial dilated cardiomyopathy, or FDC, including 216 adults and 129 children. Up to 20 percent of adult family members with no other cardiovascular conditions were found to be affected with FDC. More than 80 percent of those affected had no cardiac symptoms.
The study recommends that individuals diagnosed with IDC be informed about the genetic risk, that a thorough family history be taken and that the screening of first-degree relatives (parents, siblings and children) should follow. Screening includes a medical history and exam by a physician, an electrocardiogram and an echocardiogram. The echocardiogram examines the heart chamber sizes and functions.
"The key issue raised by this study is that physicians need to understand that IDC can be a genetic disease," said Ray Hershberger, M.D., associate professor of cardiology at Oregon Health Sciences University and head of the OHSU Heart Failure and Heart Treatment Program. "These new insights require a change in our practice patterns."
As part of this ongoing study to find the gene(s) that cause familial dilated cardiomyopathy (FDC), Hershberger and colleagues are working with more than a dozen families with FDC. Supported by the National Heart Lung and Blood Institute of the National Institutes of Health, they have completed 17 trips to 13 states to screen more than 500 relatives. Those family members discovered to have cardiac abnormalities are referred to their local physicians for further testing and medical counseling.
The research group is composed of clinical and basic scientists. A web site at www.fdc.to provides additional information for health care professionals and family members with dilated cardiomyopathy.