5 Common Congenital Heart Defects

A congenital heart defect occurs when the heart or blood vessels near the heart don't develop normally before birth.

Congenital cardiovascular defects, ranging from mild to severe, occur in about one percent of all live births, or approximately eight out of every 1,000 births, and are the most common congenital malformation in newborns.

Although the exact reason for the problem isn't clear, according to the American Heart Association, viral infections can sometimes cause the defect. For example, if a pregnant woman contracts German measles, it can interfere with the development of the baby's heart causing a malformation. Heredity may also play a role in congenital heart defects, as may other genetic disorders, such as Down's syndrome.

Congenital heart defects disrupt the normal flow of blood through the heart, causing blood flow to:

  • Slow down
  • Go in the wrong direction or to the wrong place
  • Be blocked completely

Treatment for the problem can range from medicines, surgery and other medical procedures to heart transplants.


Here are five common congenital heart defects:
1. Aortic Valve Stenosis (AVS)-In this heart defect, the aortic valve leading from the heart to the body does not open and close properly and may also leak blood. When blood flow is blocked, pressure may build up inside the heart, causing damage.

2. Atrial Septal Defect (ASD)-Atrial septal defect is a hole in the wall that separates the top two chambers of the heart, allowing oxygen-rich blood to leak into the oxygen-poor blood chambers in the heart.

3. Coarctation of the Aorta (CoA)-In this congenital heart defect, a narrowing of the aorta, a major artery, obstructs blood flow to the lower body and increases blood pressure. This type of defect may require surgery soon after birth and usually has a favorable outcome, although long-term follow-up care is necessary.

4. Complete Atrioventricular Canal Defect (CAVC)-In this type of heart defect, there is a large hole in the center of the heart, preventing the four chambers of the heart from working properly, allowing blood to mix and the chambers and valves to improperly circulate blood throughout the body.

5. d-Transposition of the Great Arteries-In this condition, the two main arteries carrying blood away from the heart are reversed. In a normal blood pattern, the cycle is: body-heart-lungs-heart-body. When a d-transposition happens, the blood pathway is impaired, causing the blood flow cycle to be stuck in a pattern of either:

  • Body-heart-body (without being routed to the lungs for oxygen) or
  • Lungs-heart-lungs (without delivering oxygen to the body)

This condition usually requires surgery to correct.

American Heart Association. "Congenital Cardiovascular Defects."

MedlinePlus: U.S. National Library of Medicine. "Congenital Heart Defects."