What is an Atrial Septal Defect?

An Atrial Septal Defect (ASD) is a hole in the wall (septum) that separates the right and left atria (the two smaller chambers of the heart). This allows a portion of the blood coming back from the lungs to pass from the left atrium to the right atrium, and then back to the lungs, without passing to the body.

The amount of blood coming back from the lungs that passes through the hole depends on the size of the hole. If the hole is large enough, then the blood passing through the hole will cause the right atrium and right ventricle to be enlarged, and the excess blood flow to the lungs could cause damage to the small arteries in the lungs.

What are the warning signs and symptoms of Atrial Septal Defect?

There usually are no obvious signs or symptoms of ASDin a newborn or a child. Occasionally, growth will be slow or there may be more frequent pulmonary infections (having to do with the lungs). An appointment with a pediatric cardiologist is usually requested because of the presence of an abnormal heart murmur. (A murmur is a sound – heard usually with a stethoscope – due to vibrations from the flow of blood through the heart; it may be of no significance or it may reflect disease.) Long-standing enlargement of the right heart may cause abnormal heart rhythms in adults.

How is Atrial Septal Defect detected?

An abnormal heart murmur is usually the first clue to the presence of congenital heart disease. Often an echocardiogram will be done. It is important to precisely determine the location and size of the hole using echocardiography. (An echocardiogram is a test that provides pictures of the heart’s valves and chambers to evaluate the pumping action of the heart.)

What are the treatment options for Atrial Septal Defect?

A small ASD generally does not cause complications in childhood and no treatment is required. If found in infancy, many of these will close on their own with time.

If the Atrial Septal Defect is large enough to cause cardiac enlargement, and has not gotten any smaller after several years of age, then closure of the ASD is necessary. For many years, the treatment was open-heart surgery, either by simply stitching the hole closed or by sewing a patch over the hole to close it. The patch is generally obtained from the wall of the sac surrounding the heart.

A newer, non-surgical approach to ASD closure has been developed and is becoming widely used. A catheter is threaded from a vein in the groin, up through the venous system to the right atrium, and then across the hole. An umbrella-like device is then threaded through the catheter and placed in a position that straddles the hole to seal it. The catheter itself is then removed.

6/16/2008