March 24, 1999
FOR RELEASE: Upon Receipt
CONTACT: Lynda Majarian, 802-656-7875
[email protected]
OR
Rick Blount, 802-656-1108
[email protected]
VERMONT STUDY TARGETS "SILENT KILLER" IN THE HEART
Some 544,000 Americans might have a time bomb ticking in their chests -- an incurable genetic heart disorder called familial hypertrophic cardiomyopathy (FHC) that most often strikes seemingly healthy young adults. FHC is the most common cause of sudden cardiac death in people under age 35. The congenital disease can be triggered by a change in exercise level, and is the cause of death for about half the athletes who die suddenly -- such as Boston Celtics basketball player Reggie Lewis, who died on the court in 1993.
Some people with FHC live long, productive lives despite the condition; others may exhibit symptoms such as chest pain, dizziness, or shortness of breath. "But often, the first symptom is death," said David Warshaw, Ph.D., chair of the Department of Molecular Physiology and Biophysics at the University of Vermont (UVM). Warshaw is lead investigator of a new FHC study, made possible through a five-year program project grant of $7.2 million from the National Institutes of Health. Four UVM laboratories, plus researchers at Harvard University and Johns Hopkins University, constitute one of the only multidisciplinary teams of investigators to address the disease.
It is believed that FHC begins with a genetic mutation in the heart's myosin molecules. Myosin is one of the main proteins of the heart, and works with a second protein to function as the heart's molecular motor. "Like a car motor, the mechanical function of this molecular motor is made up of many parts," Warshaw explained. "Changing one part may compromise how the entire motor functions." Researchers suspect that the muscle of the heart thickens, or enlarges, to compensate for the myosin defect, impeding both the flow of blood through the heart and the heart's ability to pump blood to the rest of the body.
As they follow the course of FHC from the mutation in the myosin molecule to an enlarged heart, Warshaw and his colleagues hope to understand how and when the disease becomes lethal. Researchers will form three groups to study the mechanical properties of the whole heart, conduct tests on a single muscle fiber, and access the force and motion of individual myosin molecules.
"Our objective is to discover at what point we can intervene and treat the disease," Warshaw said. The scientists also hope to acquire information that will help in the development of a diagnostic test to detect the presence of the mutation in families with a predisposition for FHC.
- 30 -
RSS