Health Library

Congenital Heart Disease

What is Congenital Heart Disease?

One out of every 100 infants 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 commonly occurring birth defect.

A baby's heart begins to develop at conception, and is completely formed by eight weeks into the pregnancy. Congenital heart defects happen during these crucial first eight weeks of the baby’s development. 

Often, congenital heart defects are a result of these crucial steps not happening at the right time, or in the correct order, which means the child may be born with a single blood vessel where two ought to be or a communication (hole) between two heart chambers that should be separate.

Causes of Congenital Heart Defects

The majority of congenital heart defects have no known cause. Mothers (and fathers) often wonder if something they did during the pregnancy caused the heart problem. This is rarely the case.

Some unique congenital heart defects do occur more often in families, suggesting that there may be a genetic link. However, this is usually not the cause of most types of congenital heart defects.

Rarely, some congenital heart defects occur if the mother had a particular disease while pregnant (example: rubella) or was taking specific medications (example: anti-seizure medicines).

Importantly, in the majority of cases, there is no identifiable reason as to why the heart defect occurred.

Types of Congenital Heart Defects

Congenital heart defects range from simple to complex. Some can be watched by the child's physician and managed with or without medications, while others will require surgery, sometimes as soon as in the first few hours after birth.

A child may even "grow out" of some of the simpler heart defects, such as patent ductus arteriosus (PDA) or atrial septal defect (ASD), as these defects may resolve on their own as the child grows.

Other infants will have a combination of defects and require several operations throughout their lifetime.

Congenital heart defects can be classified into several categories in order to better understand the problems the baby will experience.

Too Much Blood Passes through Lungs

These defects allow oxygen-rich (red) blood that should be traveling to the body to recirculate through the lungs, causing increased pressure and stress in the lungs. Examples include:

Too Little Blood Passes through 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 "blue." Examples include:

Too Little Blood Travels to 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. Examples include:

Combination of Defects

Sometimes, there will be a combination of several heart defects, making for a more complex problem that can fall into several of these categories.

Who Treats These Conditions?

Babies with congenital heart problems are treated by specialists called pediatric cardiologists. These physicians diagnose heart defects and help manage the health of children before and after surgical repair of the heart problem.

Specialists who surgically correct heart problems in the operating room are known as pediatric cardiovascular or cardiothoracic surgeons. 


Last Updated 06/2020

Reviewed By Andrea Roberts, RN, Education Specialist II