Amniotic Stem Cells Offer Hope Against Congenital Heart Defects

TUESDAY, Nov. 14 (HealthDay News) -- A young mother-to-be learns her 5-month-old fetus has a congenital heart defect.

Today, this news is met with anger, sorrow, denial. Doctors will watch the unborn baby closely and may even be able to correct the problem. But the fact remains that congenital heart disease is responsible for more deaths in the first year of life than any other birth defects, the National Institutes of Health reports.

But if findings from a Swiss study prove true, in the future doctors will be able to use a simple procedure to extract stem cells from the mother's amniotic fluid and use them to make a new heart valve, ready to place in the baby as soon as it is born.

"We have demonstrated that, based on a cell source which you can obtain prenatally, you can fabricate a living heart valve from these cells which may be ready to use at the time of birth," said study senior author Dr. Simon Hoerstrup, director of cardiovascular research and the division of regenerative medicine at University Hospital in Zurich. "This may open a whole new therapy concept for the treatment of congenital heart disease."

Hoerstrup presented his paper Tuesday at the American Heart Association's annual meeting, in Chicago.

According to Hoerstrup, some 1 percent of newborns have congenital heart problems and one-third of these babies need surgery for a heart valve.

"It's a substantial group of patients," he said.

Malformation of the heart or one of its valves can be diagnosed by ultrasound in the 20th week of pregnancy. Amniotic stem cells can be obtained as part of a routine procedure already in use to search for genetic problems, especially in women over the age of 35.

For this study, Hoerstrup and his colleagues extracted amniotic stem cells, created miniature heart scaffolds, then watched them grow into functioning valves.

"The concept is that we can obtain cells during pregnancy and use the cells to create a living heart valve replacement, which is ready to use at birth," Hoerstrup said. "Advantages are that they are made from the baby's own cells and are living and can grow with the baby later on."

Although not yet transplanted into a baby, the valves created by Hoerstrup did function. "We saw a very nice opening-and-closing behavior," he said.

This study was one of several in the area of tissue reengineering presented at the heart association meeting.