What is Atrial Septal Defect (ASD)?

A hole between the right and left atria is called an atrial septal defect. This is one of the most common types of congenital heart defects diagnosed in older children. There are several types of ASDs, depending on their number, location or whether they involve the atrioventricular valves (see Atrioventricular Septal Defects) or the pulmonary veins (Sinus Venosus Defect).

Effects and Symptoms

Most children do not have symptoms. Large defects can result in too much blood flow to the lungs causing breathing difficulty or exercise intolerance.

Diagnosis

ASDs are often found incidentally, and may be associated with other congenital heart defects, or with genetic conditions. A murmur can sometimes be heard, but may not be audible in young infants. A chest xray can show a large heart and prominent lung markings can be present. An echocardiogram is also helpful in diagnosing an ASD.

Management and Treatment

ASDs can close spontaneously depending on its size and location. They can be closed with a device introduced by cardiac catheterization or closed surgically. Cardiology follow-up is done in childhood until after device or surgical closure.

Medications are typically not needed unless a heart rhythm problem is present.

Surgery

If the ASD should be closed, open heart surgery may be necessary. The ASD is closed by either stitches or a patch, and long term outcomes are very favorable.

Adult and Adolescent Management

When ASDs are left unrepaired into adulthood, the right side of the heart may become enlarged and the walls of the atrial walls are stretched. This can cause abnormal heart rhythms called atrial arrhythmias. Long term and excessive blood flow to the lungs can result in an increase in pressures in the lung arteries and cause decreased oxygen to the body and symptoms of fatigue. The communication between the left and right side of the heart can increase the risk for stroke in adults with unrepaired ASDs.

‍