What Is a Congenital Heart Defect?
A congenital heart defect is a structural problem (or defect) in the heart that is present at birth. A baby’s heart begins to develop shortly after conception. During development, structural defects can occur. These defects can involve the walls of the heart, the valves of the heart, and the arteries and veins near the heart. Congenital heart defects can disrupt the normal flow of blood through the heart.
The blood flow can:
Go in the wrong direction or to the wrong place
Be blocked completely
Congenital heart defect is the most common type of major birth defect. Each year, more than 30,000 babies in the United States are born with congenital heart defects. There are many types of congenital heart defects.
Abnormal passages in the heart or between blood vessels
Problems with the heart valves
Problems with the placement or development of blood vessels near the heart
Problems with development of the heart itself
Some of these problems are described below.
* Abnormal passages in the heart or between blood vessels.
* Atrial septal defect (ASD) is a hole in the wall that separates the upper chambers (atria) of the heart. This causes blood to leak from one atrium to the other.
* Ventricular septal defect (VSD) is a hole in the wall that separates the lower chambers (ventricles) of the heart. This causes blood to leak from one ventricle to the other.
* Atrioventricular septal defect (AVSD) includes an ASD, VSD, and abnormal development of the atrioventricular valves (tricuspid and mitral). This causes blood to flow abnormally inside the heart. An AVSD is also known as an atrioventricular canal defect.
* Patent ductus arteriosus (PDA) is a persistent connection between the aorta and the pulmonary artery. This connection is called the ductus arteriosus and is normally present before birth. In most babies, the vessel closes within a few hours or days after birth. In some children, the vessel fails to close, resulting in PDA.
Problems with the heart valves.
Congenital heart defects can involve any of the valves and include the following types of problems:
Stenosis. The valve opening is narrow and does not open completely.
Atresia. The valve does not form, so there is no opening for blood to pass from one chamber to another.
Regurgitation. The valve does not close completely, so blood can leak back through the valve.
Examples of particular heart valve problems include:
Aortic valve stenosis is a narrowing of the aortic valve in the heart that causes it to open incompletely. This can reduce blood flow to the body.
Pulmonary valve atresia is a defect in which a solid sheet of tissue forms in place of the pulmonary valve. This prevents blood in the right side of the heart from traveling normally to the lungs to pick up oxygen.
Pulmonary valve stenosis is a narrowing of the pulmonary valve. The narrowing slows the flow of blood from the right side of the heart to the lungs. The heart must pump harder to push blood through the smaller opening.
Tricuspid valve atresia is a defect in which a solid sheet of tissue forms in place of the tricuspid valve. Without the tricuspid valve, blood entering the right atrium cannot travel normally to the right ventricle and then to the lungs to pick up oxygen.
Ebstein’s anomaly is a defect in which the tricuspid valve is both displaced and abnormally formed. The valve leaks and allows blood to flow back into the right atrium instead of to the lungs to pick up oxygen.