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what is a congenital heart defect 

 What is a Congenital Heart Defect?  

Congenital heart defects are abnormalities in the heart's structure that are present at birth and range from mild to severe. This means that the heart may not pump blood well, beat correctly or allow blood to flow normally through its chambers or arteries. The incidence of congenital heart defects occurs in one out of every 125 newborns, approximately 35,000 children.

Almost all children with congenital heart defects grow up to have happy, active, productive lives.  1.4 million children and adults live with congenital heart defects.

The most common congenital heart defects are hypoplastic left heart syndrome, ventricular septal defect, heart murmur and arrhythmia.

Hypoplastic left heart syndrome (HLHS)

When the structures of the left side of the heart (the left ventricle, the mitral valve and the aortic valve) are not fully developed, they're unable to pump blood adequately to the entire body. HLHS is usually diagnosed within the first few days of life, at which point the baby may be critically ill.

Fortunately, many of these infants are recognized to have serious heart disease even before birth on ultrasound tests. A fetal echocardiogram is an ultrasound that allows a pediatric cardiologist to see the details of baby's heart and diagnose the problem and plan the best care for when Baby is born.

Ventricular Septal Defect (VSD)

One of the most common congenital heart defects, ventricular septal defect (VSD) is a hole in the wall (septum) between the heart's left and right ventricles. VSD can occur at different locations and it can vary in size. Some of the smaller defects may gradually close up and not cause any problems. As a result, some oxygenated blood from the left atrium flows through the hole in the septum into the right atrium, where it mixes with oxygen-poor blood and increases the total amount of blood that flows toward the lungs. The increased blood flow to the lungs creates a swishing sound, known as a heart murmur. This heart murmur, along with other specific heart sounds that can be detected by a cardiologist, can be clues that a child has a ventricular heart defect.

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An arrhythmia (also called dysrhymthia) is an abnormal heart rhythm caused by an electrical “short circuit” in the heart.  The electrical signals flowing through the heart don’t communicate properly with the heart muscle.

The heart normally beats in a consistent pattern, but an arrhythmia can make it beat too slowly, too quickly or irregularly. This can cause the heart muscle's pumping function to work erratically, which can lead to a variety of symptoms, including fatigue, dizziness, and chest pain.

Heart Murmur

A heart murmur is a noise that the blood makes as it flows through the heart. Typically blood flows silently.  It is when blood starts to flow more rapidly that noise is produced, which can be heard by listening with the stethoscope and is called "heart murmur." A heart murmur does not mean that there is anything wrong with your child's heart. Heart murmurs are common in children and are usually harmless. These noises are commonly heard in children because their hearts are very close to their chest walls.

An abnormal (pathologic) heart murmur indicates a problem with the structure of the heart. Problems that can cause this type of heart murmur include a hole in the heart or a leaky or narrow heart valve.

What causes a congenital heart defect?

In most cases, we don’t know what makes a baby's heart develop abnormally. Congenital heart defects occur within the first few weeks of life.  Genetic and environmental factors appear to affect babies while in the womb. These can include:

Gene mutations

Mothers who have Rubella (measles) or flu during the first trimester

Alcohol and cocaine use

Certain medications

Chronic illness in mother such as diabetes

30% of children with chromosomal abnormalities and inherited disorders have heart defects


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