About four people in every 100,000 have Atrial Septal Defect (ASD), which is a heart condition present from birth. An ASD is a hole, or similar defect, in the wall of the atrium, which is the upper chamber of the heart. In fetal circulation, the existing hole between the atria allows blood to bypass the lungs. However, during fetal development, this hole between the left and right atrium should close, but it does not always close before birth. If the opening persists beyond birth, an atrial septal defect can result.

There is no known way to prevent the defect, but some of the complications can be prevented with early detection. When no other congenital defect co-exists, symptoms may be absent, particularly in children. Atrial septal defect may be discovered during a routine physical examination and confirmed with an echocardiogram.

Normal Heart	Atrial Septal Defect

For most other patients, symptoms typically appear by age 30. When symptoms appear, they usually manifest themselves as fatigue and shortness of breath. Other symptoms that may occur include frequent respiratory infections, difficulty breathing (dyspnea), shortness of breath with activity, and the sensation of feeling rapid heartbeats (palpitations).

With a small-to-moderate atrial septal defect, a person may live a normal life span without symptoms. Larger defects may cause disability by middle age because of increased blood flow and shunting of blood back into the pulmonary (lung) circulation.

If left untreated, an atrial septal defect can result in heart failure or stroke. Individuals with an atrial septal defect may also develop complications including infective endocarditis (a bacterial infection of the heart), heart failure and an abnormally fast heart rhythm known as atrial fibrillation.

Atrial septal defect repair may not require treatment if there are few or no symptoms, or if the defect is small. Surgical closure of the defect is recommended if the ASD is large or if symptoms occur.

This information is not an alternative to direct communication with your health care providers. We hope it will help you to start a dialogue that will lead to the best option for you or your loved one.