Cardiac Center

The Underlying Causes of Heart Defects

The heart is one of the first organs to form in the fetus. It begins as a straight, single heart tube which bends, grows and divides into a four-chambered pump.

Approximately 1 in 125 babies is born with a congenital heart defect.

Why do their hearts form incorrectly?

The genetic code holds some of the answers — answers that could lead to better methods of treatment and prevention.

Elizabeth Goldmuntz, MD, a pediatric cardiologist at CHOP for 14 years, is part of a group of researchers here studying underlying causes of heart defects.

In one of the largest studies of its kind, her team has collected data on more than 1,300 patients with conotruncal heart defects and 800 patients with left-sided heart defects, which begin in the earliest stages of fetal heart development.

Goldmuntz is studying the relationship between genes and heart defects. She is also taking the research a step further by examining whether genes affect patient outcomes, such as survival rates after open-heart surgery and long-term health.

“We hope we can find out why a child is born with a heart defect, and then find ways to prevent that from happening,” Goldmuntz says. “We also think that if we understand why a child is born with a heart defect, we can design better clinical and surgical strategies to improve outcome.”

The project epitomizes cardiac center research. Here, the brightest minds are supported by the best technology, generous donors, and large numbers of families willing to take part because they trust their doctors and believe their research may someday prevent another child from going through what their children have experienced.

A look back and to the future

Since 1997, when the current projects began, genetic counselors have approached parents of patients with conotruncal and left-sided defects, explaining the research and asking them to participate.

“Most families are willing to participate, hoping not only to find an answer for their child, but to help other families in the future,” says Jennifer Garbarini, MS, CGC, a cardiac center genetic counselor who works with Goldmuntz.

When parents agree, the counselors interview them about pregnancy and family medical history and collect patient medical records, including electrocardiograms and echocardiograms. blood is obtained from patients (often from an IV line already in place); blood or saliva is also collected from their parents and, when possible, grandparents.

For a related part of the research, patients with conotruncal defects return to CHOP years after their surgery for a day of testing, including an echocardiogram, cardiac MRI and exercise-stress test. patients and their parents are asked another series of questions, this time about issues such as length of recovery after surgery and overall quality of life.

Information from the first and second phases of the research is entered into a database. Goldmuntz uses a variety of cutting-edge scientific techniques, along with the information from the database, to search for answers. She is looking for any genetic change that may alter the normal development of the heart.

So far, Goldmuntz and her team have studied more than a dozen genes and found small changes in several that may relate to why a child is born with a heart defect. they are also using new techniques to study the entire human genome, or set of genes, all at once for changes. In addition, they have some early data that may help identify families at greatest risk for having a child with a heart defect and ways to decrease that risk. Finally, more than 100 children and adolescents have returned for clinical testing and gene studies to assess how genes affect clinical outcome.

“in the future, we will continue to study how changes in genes lead to heart defects and how genes influence how well each child does over their lifetime,” Goldmuntz says.

The project is one of five under a CHOP program called the Specialized Center of Clinically Oriented Research in Pediatric Heart Development and Disease. (“Clinically oriented” means patient-focused.)

Research funding

Like many of our research projects, funding comes from numerous sources. Goldmuntz is primarily supported by the National Institutes of Health (NIH), the government agency that supports scientific research; but an individual donor, Ida Newman, who is committed to research in this area, has provided significant additional funding. Newman first supported Goldmuntz as a fellow in training and has continued to fund these studies.

Goldmuntz is currently trying to renew her funding from the NIH to continue this work. Given the increasingly limited resources coming from the NIH, Goldmuntz and other researchers need additional sources of support. By making a contribution to the Cardiac Center, you serve as that support. You help doctors like Elizabeth Goldmuntz pursue important and unique studies with the potential to reach a tiny heart, forming in the womb.

Download the PDF version of Let's Stand at the Very Beginning.

  • Print
  • Share

Contact Us

For a second opinion, cardiac referral, or for more information.

To schedule an outpatient appointment.

Get Driving Directions