Congenital Heart Defects

According to the American Heart Association, about eight of every 1,000 babies born in the United States has a congenital (present at birth) heart defect – a problem that occurred as the baby's heart was developing during pregnancy, before the baby is born. Congenital heart defects are the most common birth defects.

A baby's heart begins to develop at conception, but is completely formed by eight weeks into the pregnancy. Congenital heart defects happen during this crucial first eight weeks of the baby's development. Specific steps must take place in order for the heart to form correctly. Often, congenital heart defects are a result of one of these crucial steps not happening at the right time, leaving a hole where a dividing wall should have formed, or a single blood vessel where two ought to be, for example.

Lehigh Valley Health Network offers care for congenital heart disease for your child or teen. These services are affiliated with Lehigh Valley Reilly Children's Hospital. We are the region’s only associate member of the Children’s Hospital Association (CHA).

The vast majority of congenital heart defects have no known cause. Mothers will often wonder if something they did during the pregnancy caused the heart problem. In most cases, nothing can be attributed to the heart defect. Some heart problems do occur more often in families, so there may be a genetic link to some heart defects. Some heart problems are likely to occur if the mother had a disease while pregnant and was taking medications, such as anti-seizure medicines or the acne medication isotretinoin. However, most of the time there is no identifiable reason as to why the heart defect occurred.

“Many newborns with a heart defect will display noticeable symptoms, such as a bluish tint to the skin, rapid breathing, and cold sweats,” says pediatric cardiologist Louis Hansrote, MD, with Lehigh Valley Health Network. “In addition to those symptoms, your child may nurse slowly, consume very little breast milk or formula, or fail to gain weight.”

Congenital heart problems range from simple to complex. Some heart problems can be watched by the baby's doctor and managed with medicines, while others will require surgery, sometimes as soon as in the first few hours after birth. A baby may even "grow out" of some of the simpler heart problems, such as patent ductus arteriosus (PDA) or atrial septal defect (ASD), since these defects may simply close up on their own with growth. Other babies will have a combination of defects and require several operations throughout their lives.

We can classify congenital heart defects into several categories in order to better understand the problems the baby will experience. They include:

• Problems that cause too much blood to pass through the lungs – These defects allow oxygen-rich blood that should be traveling to the body to re-circulate through the lungs, causing increased pressure and stress in the lungs.
• Problems that cause too little blood to pass through the lungs – These defects allow blood that has not been to the lungs to pick up oxygen (and therefore is oxygen-poor) to travel to the body. The body does not receive enough oxygen with these heart problems, and the baby will be cyanotic, or have a blue coloring.
• Problems that cause too little blood to travel to the body – These defects are a result of underdeveloped chambers of the heart or blockages in blood vessels that prevent the proper amount of blood from traveling to the body to meet its needs.

Some of the problems that cause too much blood to pass through the lungs include the following:

Patent ductus arteriosus (PDA)

This defect, which normally occurs during fetal life, short-circuits the normal pulmonary vascular system and allows blood to mix between the pulmonary artery and the aorta. Prior to birth, there is an open passageway between the two blood vessels, which closes soon after birth. When it does not close, some blood returns to the lungs. Patent ductus arteriosus is often seen in premature infants.

Atrial septal defect (ASD)

In this condition, there is an abnormal opening between the two upper chambers of the heart – the right and left atria – causing an abnormal blood flow through the heart. Some children may have no symptoms and appear healthy. However, if the ASD is large, permitting a large amount of blood to pass through the right side, symptoms will be noted.

Ventricular septal defect (VSD)

In this condition, a hole in the ventricular septum (a dividing wall between the two lower chambers of the heart – the right and left ventricles) occurs. Because of this opening, blood from the left ventricle flows back into the right ventricle, due to higher pressure in the left ventricle. This causes an extra volume of blood to be pumped into the lungs by the right ventricle, which can create congestion in the lungs.

Atrioventricular canal (AVC or AV canal)

Atrioventricular canal is a complex heart problem that involves several abnormalities of structures inside the heart, including atrial septal defect, ventricular septal defect, and improperly formed mitral and/or tricuspid valves. A complex combination of heart defects known as hypoplastic left heart syndrome also can occur.

Hypoplastic left heart syndrome (HLHS)

This is a combination of several abnormalities of the heart and the great blood vessels. In hypoplastic left heart syndrome, most of the structures on the left side of the heart (including the left ventricle, mitral valve, aorta and aortic valve) are small and underdeveloped. The degree of underdevelopment differs from child to child. The functional ability of the left ventricle can be reduced to the extent of not being able to pump an adequate blood volume to the body. Hypoplastic left heart syndrome can be fatal without treatment.

Will your child survive a heart defect?

“The answer to that question depends on the type of defect your child has,” Hansrote says. “The most common heart defect is a small hole in the wall between the lower chambers of the heart. Many of these holes heal without treatment. Even if your child has a more serious defect that requires surgery, the outlook is much more positive than it was 20 years ago.”

Follow-up care

Babies with congenital heart problems are followed by specialists called pediatric cardiologists. These doctors diagnose heart defects and help manage the health of children before and after surgical repair of the heart problem. Specialists who correct heart problems in the operating room are known as pediatric cardiovascular or cardiothoracic surgeons.

A new subspecialty within cardiology is emerging as the number of adults with congenital heart disease (CHD) is now greater than the number of babies born with CHD, as a result of the advances in diagnostic procedures and treatment interventions that have been made since 1945.

In order to achieve and maintain the highest possible level of wellness, it is imperative that those individuals born with CHD who have reached adulthood transition to the appropriate type of cardiac care. The type of care required is based on the type of CHD a person has. Those people with simple CHD can generally be cared for by a community adult cardiologist. Those with more complex types of CHD will need to be cared for at a center that specializes in adult CHD.

For adults with CHD, guidance is necessary for planning key life issues such as college, career, employment, insurance, activity, lifestyle, inheritance, family planning, pregnancy, chronic care, disability and end of life. Knowledge about specific congenital heart conditions and expectations for long-term outcomes and potential complications and risks must be reviewed as part of the successful transition from pediatric care to adult care. Parents should help pass on the responsibility for this knowledge and accountability for ongoing care to their young adult children to help ensure the transition to adult specialty care and optimize the health status of the young adult with CHD.