An atrial septal defect (ASD) is a hole in the wall between the two upper chambers of your heart (atria). The condition is present at birth (congenital).
Small defects may never cause a problem and may be found incidentally. It's also possible that small atrial septal defects may close on their own during infancy or early childhood.
Large and long-standing atrial septal defects can damage your heart and lungs. An adult who has had an undetected atrial septal defect for decades may have a shortened life span from heart failure or high blood pressure that affects the arteries in the lungs (pulmonary hypertension). Surgery may be necessary to repair atrial septal defects to prevent complications.
Atrial septal defect care at Mayo Clinic
Many babies born with atrial septal defects don't have associated signs or symptoms. In adults, signs or symptoms may begin around age 30, but in some cases signs and symptoms may not occur until decades later.
Atrial septal defect signs and symptoms may include:
Contact your doctor if you or your child has any of these signs or symptoms:
These could be signs or symptoms of heart failure or another complication of congenital heart disease.
The heart is divided into four hollow chambers, two on the right and two on the left. To pump blood throughout the body, the heart uses its left and right sides for different tasks.
The right side of the heart moves blood to the lungs through vessels called pulmonary arteries. In the lungs, blood picks up oxygen then returns to the heart's left side through the pulmonary veins. The left side of the heart then pumps the blood through the aorta and out to the rest of the body.
Doctors know that heart defects present at birth (congenital) arise from errors early in the heart's development, but there's often no clear cause. Genetics and environmental factors may play a role.
An atrial septal defect (ASD) allows freshly oxygenated blood to flow from the left upper chamber of the heart (left atrium) into the right upper chamber of the heart (right atrium). There, it mixes with deoxygenated blood and is pumped to the lungs, even though it's already refreshed with oxygen.
If the atrial septal defect is large, this extra blood volume can overfill the lungs and overwork the right side of the heart. If not treated, the right side of the heart eventually enlarges and weakens. If this process continues, the blood pressure in your lungs may increase as well, leading to pulmonary hypertension.
Atrial septal defects can be several types, including:
Your or your child's doctor may first suspect an atrial septal defect or other heart defect during a regular checkup if he or she hears a heart murmur while listening to the heart using a stethoscope.
If your doctor suspects you or your child has a heart defect, the doctor may request one or more of the following tests:
Echocardiogram. This is the most commonly used test to diagnose an atrial septal defect. Some atrial septal defects can be found during an echocardiogram done for another reason.
During an echocardiogram, sound waves are used to produce a video image of the heart. It allows your doctor to see your heart's chambers and measure their pumping strength.
This test also checks heart valves and looks for any signs of heart defects. Doctors may use this test to evaluate your condition and determine your treatment plan.
Cardiac catheterization. In this test, a thin, flexible tube (catheter) is inserted into a blood vessel at your groin or arm and guided to your heart. Through catheterization, doctors can diagnose congenital heart defects, test how well your heart is pumping and check the function of your heart valves. Using catheterization, the blood pressure in your lungs also can be measured.
However, this test usually isn't needed to diagnose an atrial septal defect. Doctors may also use catheterization techniques to repair heart defects.
A small atrial septal defect may never cause any problems. Small atrial septal defects often close during infancy.
Larger defects can cause serious problems, including:
Less common serious complications may include:
Treatment can prevent or help manage many of these complications.
Most women with an atrial septal defect can tolerate pregnancy without any problems. However, having a larger defect or having complications such as heart failure, arrhythmias or pulmonary hypertension can increase your 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, whether in the father or the mother. Anyone with a congenital heart defect, repaired or not, who is considering starting a family should carefully discuss it beforehand with a doctor. Some medications may need to be stopped or adjusted before you become pregnant because they can cause serious problems for a developing fetus.
In most cases, atrial septal defects can't be prevented. If you're planning to become pregnant, schedule a preconception visit with your health care provider. This visit should include:
If you find out you have a congenital heart defect, or you've had surgery to correct one, you may wonder about limitations on activities and other issues.
Exercise. Having an atrial septal defect usually doesn't restrict you from activities or exercise. If you have complications, such as arrhythmias, heart failure or pulmonary hypertension, you may not be able to do some activities or exercises. Your cardiologist can help you learn what is safe.
If you have an unrepaired defect, your doctor will likely advise you to avoid scuba diving and high altitude climbing.
Preventing infection. Some heart defects and the repair of defects create changes to the surface of the heart in which bacteria can become stuck and grow into an infection (infective endocarditis). Atrial septal defects generally aren't associated with infective endocarditis, though your doctor will likely recommend preventive antibiotics for about six months after closure whenever you have dental work done.
But if you have other heart defects in addition to an atrial septal defect, or if you've had atrial septal defect repair within the last six months, you may need to take antibiotics before certain dental or surgical procedures.
It's not known why atrial septal defects occur, but congenital heart defects appear to run in families and sometimes occur with other genetic problems, such as Down syndrome. If you have a heart defect, or you have a child with a heart defect, a genetic counselor can estimate the odds that any future children will have one.
Some conditions that you have or that occur during pregnancy may increase your risk of having a baby with a heart defect, including: