Congenital Heart Defects Congenital heart defects are structural problems that are present at birth. The defects may affect the structure of the heart, the heart valves or blood vessels leading to or from the heart.

According to the National Heart, Lung and Blood Institute, about 30,000 babies are born each year with some type of congenital heart defect. Doctors have identified at least 35 different types of congenital heart defects. The following is a brief description of the some of the most common problems:

Ventricular septal defects. The heart has four chambers - two at the top (the atria) and two at the bottom (the ventricles). The upper and lower chambers are divided by a wall called the septum. A ventricular septal defect is a hole in the wall between the two lower chambers of the heart. The abnormal opening allows blood from the left ventricle (the main pumping chamber of the heart) to flow back into the right ventricle. The heart needs to work harder to get enough blood to the body and may become overworked and enlarged.

Atrioventricular septal defects. In this condition, there is a hole in the wall of the center of the heart where the upper chambers meet the lower chambers. Children born with this condition also have abnormal heart valves. Instead of having two valves (one on each side of the upper and lower chambers), only one large valve forms. Oxygen-rich blood from the left side of the heart flows back into the right side and mixes with the oxygen-depleted blood. The heart must work harder and may enlarge. The condition is also known as atrioventricular canal defect.

Transposition of the Great Arteries. In the normal heart, the aorta (the main artery carrying oxygenated blood from the heart to the body) is connected to the left ventricle, and the pulmonary artery (the vessel that carries oxygen-depleted blood to the lungs) is connected to the right ventricle. In transposition of the great arteries, the positions of the two main arteries are switched - the aorta is attached to the right ventricle and the pulmonary artery is attached to the left ventricle. Oxygenated blood flows back to the lungs while de-oxygenated blood goes back to the body. Infants don't survive unless they have a hole in the heart (a second defect) that allows some oxygenated blood to mix in with the de-oxygenated blood.

Tetralogy of Fallot. This condition is comprised of four separate defects: (1) a ventricular septal defect, (2) narrowing of the pulmonary valve (pulmonary valve stenosis), (3) abnormal positioning of the aorta over the ventricular septal defect and (4) thickening of the right ventricle. Children with this condition don't get enough blood to the lungs, limiting the amount of oxygen that can be supplied to the body.

Surviving Congenital Heart Defects Long ago, many children with congenital heart defects died - often at birth or soon thereafter. Now, prenatal diagnosis and advances in medical and surgical treatments are saving the lives of many of these babies. According to the Adult Congenital Heart Association, about 90 percent of children born with congenital heart defects are now surviving into adulthood. Researchers now estimate nearly one million adults in the U.S. are living with congenital heart defects.

Many adult survivors of congenital heart defects consider themselves "cured" of their condition. However, researchers are now finding that many of these survivors are facing other kinds of problems as they grow older. In some cases, repaired hearts are starting to wear out or fail. Patients seem to be at higher risk for development of abnormal heart rhythms, enlarged hearts or heart failure.

Adults who were born with congenital heart defects need to be educated about the need for continual monitoring for long term complications. Gregory Johnson, M.D. a Pediatric Cardiologist in Austin, says less than half of adults with congenital heart disease get regular cardiac care. Primary care physicians also need to be aware of a patient's medical history so they can take an active role in referral if symptoms or problems occur. That will allow patients to get treatment before symptoms become severe or more serious heart damage occurs.

Finding a physician can be difficult. Only about 100 cardiologists in the U.S. are specially trained in adult congenital heart disease. Regular cardiologists may not be well-qualified to treat the different kinds of problems seen in adult survivors of heart defects. Some patients continue to see their pediatric cardiologist for care. Patients and cardiologists are asking the National Institutes of Health to develop a registry to track adult patients with congenital heart disease.

For general information on congenital heart disease, Adult Congenital Heart Association, http://www.achaheart.org American Heart Association, http://www.americanheart.org, or contact your local chapter Congenital Heart Information Network, http://tchin.org> International Society for Adult Congenital Cardiac Diseases, http://www.isaccd.org March of Dimes, http://www.marchofdimes.org, or contact your local chapter National Heart, Lung and Blood Institute, http://www.nhlbi.nih.gov