Heart Care | Congenital Heart Disease

Atrial septal defect (ASD) is an abnormal hole in the wall between the two upper chambers of the heart, called the right and left atria. When this hole occurs, too much blood flows from the left atrium to the right atrium and through the right side of the heart. This excess blood flows through the right ventricle, pulmonary artery and into the lungs making the heart work harder. The extra blood flowing to the lungs creates a noise called a murmur.

Small holes may close on their own by the time a child is 2 years old. In some people, the defect doesn't cause symptoms until middle age.

A large ASD causes several problems. The heart works harder because it pumps extra blood to the lungs, which may cause the right side of your heart to enlarge resulting in irregular heartbeats called arrhythmias. It also may cause congestive heart failure, usually in middle age. In addition, a large amount of extra blood flow damages the blood vessels in the lung. All ASDs larger than a few millimeters in diameter should be closed to prevent these problems.

Most atrial septal defects (ASD) are discovered during childhood when a murmur, an extra heart sound, is heard during a physical examination.

In addition, your doctor may use a cardiac catheterization procedure to inject a dye into the heart and to see on a moving picture X-ray how the heart and aorta are functioning.

Coronary angiography may be recommended for patients over age 40 to detect coronary artery disease.

In the past, atrial septal defect (ASD) closure required open-heart surgery through an incision in the chest using a heart-lung bypass machine. This procedure would require three to five days in the hospital for recovery. It is now possible to close ASDs without surgery.

This is done during a heart procedure called a cardiac catheterization using a "patch" or special septal repair device that is placed permanently in the heart to cover the hole. The procedure takes about three hours to complete. You will be admitted to the hospital in the morning of the procedure and discharged later that day or the following morning.

The heart catheterization consists of placing a long, thin, hollow plastic tube, called a catheter, into the blood vessel in your groin and passing it through vessels into the heart's chambers. The catheter is used to gather blood samples and pressure measurements and to inject dye for X-ray movies. The size of the ASD will be measured and an appropriate size septal repair device will be selected for closure. If an ASD is unusually large, this procedure may not be possible. Surgical closure would then be necessary and would be scheduled for another time.

A septal repair device consists of two connected patches that are permanently placed in the hole to cover both the left and right atrial sides. After placement, within the first three months, the lining of the heart wall grows over the patch and seals the hole completely. There are several devices currently available for closure. The type and size of device is chosen after X-ray and echocardiogram movie pictures determine the size and location of the hole. Sometimes more than one device is needed to completely close the hole.

The procedure is safe with effective closure of the hole in 97 percent of more than 1,500 patients tested. The remaining 3 percent had surgical closure at a later date because the hole was too large or not centered in the atrial wall. Complications during the procedure are rare and almost all can be treated immediately. These include blood loss requiring a transfusion, allergic reaction to X-ray dye requiring medication, stroke and improper device position requiring retrieval by catheter technique or surgery. There is a small risk of blockage of the groin vessels used for catheterization and ordinarily it responds to medication.

Anticoagulation medication usually is prescribed after the operation for patients who also have arrhythmia. However, the risk for infection is low so antibiotics are recommended only for the first six months after surgery. Normal activities, including pregnancy, generally are safe.

Patients who have had repair of an atrial septal defect generally have a normal life. Most women can have normal uncomplicated pregnancies. A small percentage of patients may develop pulmonary hypertension -- high pressures in the lung circulation -- or abnormal heart rhythms. For this reason, it is recommended that a cardiologist with an interest in congenital heart disease evaluate all patients at least once during adulthood. A woman contemplating pregnancy also should be evaluated prior to conception. Thereafter, yearly follow-up is prudent.