Lethal Genetic Heart Defect Found
Responsible for heart failure in some people with congential problems
THURSDAY, April 29, 2004 (HealthDayNews) -- Researchers have identified a genetic "time bomb" that eventually leads to heart failure in some people with congenital heart disease even after they've had corrective surgery.
The study found surgery on people with familial forms of congenital heart disease called atrial septal defects may not correct the underlying molecular problem that causes progressive heart failure and sudden death later in life.
In research with mice and humans, University of California, San Diego scientists found that defects in the gene Nkx2-5, which plays a critical role in embryonic heart formation, continue to cause trouble by degrading the heart's electrical wiring and by encouraging excessive overgrowth of heart tissue.
The study appears in the April 30 issue of Cell. The researchers say their findings may also apply to other forms of congenital heart disease.
Congenital heart defects are structural problems that are present at birth. They're the most common kind of birth defect in newborns.
Babies with atrial septal defects have a hole between the heart's two upper chambers. Surgery to close the hole is the most common treatment.
"If a child is born with a hole in the heart, it can be patched," study author Dr. Kenneth Chien said in a prepared statement.
"However, as these patients survive, it is now clear that there is an intrinsic, progressive problem with the heart that makes them get late-stage heart failure and, in certain cases, sudden death due to electrical problems," said Chien, a professor of medicine and director of the Institute of Molecular Medicine at UCSD.
The American College of Cardiology has more about congenital heart disease.