Definition

An atrial septal defect (ASD) is a hole in the wall between the left and right upper chambers of the heart. Blood can flow through this hole. This will make it hard for the heart to work as it should. It can also lead to a backup of fluids in the lungs.

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Causes

ASD happens as the baby grows in the uterus. It is not always known why the wall does not grow as it should. Some things that may play a role are:

• Changes in certain genes—may happen on their own or may be passed down from a parent
• Illness during the mother’s pregnancy

Risk Factors

The chances of ASD are higher if the mother:

• Used tobacco, alcohol, or antidepressants during pregnancy
• Has diabetes
• Has elevated blood glucose
• Is 35 years of age or older

Symptoms

Small holes may not cause problems right away. They may cause problems when the child is more active in later life. Problems may be:

For older children and adults:

• Breathing problems
• Fainting
• Tiring easily
• Problems doing physical activity
• Irregular heart beat— arrhythmia
• Fast heart beat— tachycardia
• Fluid buildup in the lower legs and ankles
• Bluish tint to the skin, lips, or fingernails

For babies (rare):

• Problems gaining weight
• Fast heart beat
• Repeated lung infections

Diagnosis

The doctor will ask about your symptoms and health history. A physical exam may be done. The doctor may hear a murmur while listening to the heart.

The doctor may suspect ASD based on symptoms. An echocardiogram can confirm the diagnosis.

ASD can make the right side of the heart larger. This can lead to other health issues. To look for changes to the heart your doctor may also do these tests:

• ECG —to test the heart's electrical activity
• Chest x-rays
• Cardiac catheterization —to check the heart and blood supply
• MRI scan of the heart—mostly done in adults

Treatment

Not all ASD will make the heart and lungs work harder. ASD in infants may close on their own by 3 to 5 years of age. These may not need treatment. The heart will be monitored for any changes.

People with ASD who have heart changes may need to limit certain activity. Those with smaller holes or no effects on the heart can often do all activities.

Holes that are causing stress to the heart and lungs will need treatment. The hole will be sealed with surgery or a device. Options are:

• Percutaneous procedure: A tube is inserted into a blood vessel in the thigh and passed up to the heart. A plug is used to seal the hole in the heart.
• Open heart surgery: A large incision is made in the chest and patches are used to close the hole.

Prevention

There are no known methods to prevent this health problem.