Complications

A small atrial septal defect might never cause any problems. Small atrial septal defects often close during infancy.

Larger defects can cause serious problems, including:

• Right-sided heart failure
• Heart rhythm abnormalities (arrhythmias)
• Increased risk of a stroke
• Shortened life span

Less common serious complications may include:

• Pulmonary hypertension. If a large atrial septal defect goes untreated, increased blood flow to your lungs increases the blood pressure in the lung arteries (pulmonary hypertension).
• Eisenmenger syndrome. Pulmonary hypertension can cause permanent lung damage. This complication, called Eisenmenger syndrome, usually develops over many years and occurs uncommonly in people with large atrial septal defects.

Treatment can prevent or help manage many of these complications.

Atrial septal defect and pregnancy

Most women with an atrial septal defect can go through pregnancy without problems related to the defect. However, having a larger defect or having complications such as heart failure, arrhythmias or pulmonary hypertension can increase the risk of complications during pregnancy.

Doctors strongly advise women with Eisenmenger syndrome not to become pregnant because it can endanger their lives.

The risk of congenital heart disease is higher for children of parents with congenital heart disease. Anyone with a congenital heart defect, repaired or not, who is considering starting a family should talk to a doctor. The doctor might recommend repair before pregnancy.