Aortic stenosis means that your child has a heart valve that is too narrow or is blocked. The aortic valve is one of four heart valves that keep blood flowing through the heart. The valves make sure blood flows in only one direction. The aortic valve keeps blood flowing from the left ventricle to the aorta. Your child may be born with aortic stenosis (congenital). Or it may happen later (acquired). It occurs more often in boys than in girls. Talk to your doctor if you have questions about your child's risk.

A normal aortic valve has three cusps (leaflets) that act as a one-way door. With aortic stenosis, the valve doesn't work as it should or has an abnormal number of leaflets that don't work correctly. That makes it harder for the leaflets to open and let blood flow from the left ventricle to the aorta.

Aortic stenosis may be mild, moderate, or severe. It depends on how much of the blood is blocked. The condition may get worse over time. It may also occur with other heart problems or conditions.

Moderate to severe aortic stenosis may affect the heart and blood vessels in these ways:

• Over time, the left ventricle becomes larger and can't pump blood to the body very well.
• The aorta may also become larger.
• The coronary arteries that send blood to the heart muscle may not get enough blood.

A child can be born with aortic stenosis. This means the aortic valve didn't form as it should before birth. Sometimes this problem is caused by a genetic problem. But most of the time, the cause for this isn't known. In older children, aortic stenosis may occur after an untreated strep infection.

The symptoms of aortic stenosis vary depending on how old your child is. They also vary by how severe the blockage is. For example, a child with mild aortic stenosis may have few symptoms. Or they may not have any symptoms. Symptoms may not show up until adulthood. Or a baby may have trouble feeding and may not gain weight. With severe (critical) aortic stenosis, a baby is very ill.

Severe aortic stenosis may cause:

• Fatigue or tiredness.
• Bluish discoloration around the lips or skin indicating low oxygen levels (cyanosis).
• Trouble feeding.
• Not enough weight gain.
• Dizziness or lightheadedness, especially with physical activity.
• Fainting (syncope).
• Shortness of breath or rapid breathing.
• Irregular heartbeats or feeling the heart beat (palpitations).
• Chest pain or pressure.

The symptoms of aortic stenosis can be like other health conditions. Make sure your child sees their doctor for a diagnosis.

Your child's doctor may have heard a heart murmur when listening to your child's chest with a stethoscope. A heart murmur is an abnormal sound as blood moves through the heart. A heart murmur may mean that your child has a heart defect. Your child's symptoms are also part of figuring out the diagnosis.

Your child may need to see a pediatric cardiologist to confirm the diagnosis. This is a doctor with special training to treat heart defects and other heart problems in children. Your child may also have tests, such as:

• Chest X-ray. This gives an overall picture of your child's heart and lungs.
• Electrocardiogram (ECG). This test measures the electrical activity of the heart.
• Echocardiogram (echo). This test uses sound waves to give a moving picture of the heart and valves. This is one of the best tests for aortic stenosis.
• Cardiac catheterization. This test shows details of the structures of the heart. Your child will have this test while asleep. The doctor will put a thin, flexible tube (catheter) into one of your child's blood vessels. The doctor will slowly guide the catheter to the heart. Contrast dye may be injected to let the doctor see more detail.
• Exercise testing. This allows the doctor to examine the child's ECG during exercise.
• Pulse oximetry. This noninvasive test measures oxygen levels in the blood through a sensor placed on your child's finger.

Treatment will depend on your child's symptoms, age, and general health. It will also depend on how severe the condition is. If your child doesn't have symptoms, or if symptoms are mild, your child's doctor may just watch symptoms closely. This means your child may often need office visits and tests.

The pediatric cardiologist and a cardiothoracic surgeon will figure out if your child needs an aortic valve procedure. Such procedures include:

• Balloon aortic valvuloplasty. This is done with cardiac catheterization using a catheter with a deflated balloon in the tip. The catheter is put into a blood vessel. It is moved to the narrowed valve, and the balloon is inflated to open the valve. Many doctors prefer this procedure.
• Surgical aortic valvotomy. This is surgery to remove scar tissue from the aortic valve leaflets. This lets the leaflets open as they should.
• Aortic valve replacement. This is surgery to replace the aortic valve with a new valve. Replacement valves are either artificial or from donor organs or animals.
• Pulmonary autograft (Ross procedure). This is surgery to replace the aortic valve and part of the aorta. Your child's own pulmonary valve and part of the pulmonary artery are used to replace the damaged aortic valve. A pulmonary valve and part of the pulmonary artery from a donor organ are used to replace the transplanted valve and artery. Many surgeons prefer this method because it continues to work well as a child grows.

Before the procedures:

• A baby who has critical aortic stenosis will be in an intensive care unit. They may need emergency repair of the valve. Babies who aren't as sick can have the procedure planned.
• A child with severe aortic stenosis may not be able to take part in sports. This is more a risk with sports that have intense or long periods of activity.

Possible complications of moderate to severe aortic stenosis include:

• Bulging or weakening (aneurysm) of the aorta.
• Tear (dissection) of the aorta.
• Infection of the lining of the heart, valves, or blood vessels (infective endocarditis).
• Enlargement of the heart chambers (hypertrophy).
• Heart not able to pump as it should (heart failure).
• Death.

Talk with the doctor about your child's risk for these problems.

Congenital aortic stenosis can't be prevented. But all newborns are screened for congenital heart disease with pulse oximetry. This is a simple, painless test to check the amount of oxygen in the blood. It's done by placing a small probe on the baby's arm and leg. If the oxygen level is low, it may mean there is a heart defect. More testing and treatment will be done if a problem is found.

Most children who have had an aortic valve repair or replacement live active, healthy lives. Your child's activity levels, appetite, and growth usually return to normal. Your child should get regular follow-up care with a cardiologist throughout their life. Your child may also need:

• Regular blood pressure checks and management of high blood pressure. Be sure to have your child take all medicines prescribed by their doctor.
• Regular dental care. This is to prevent infections that may lead to a heart infection (endocarditis).
• Limited physical activity. Talk with your child's doctor about safe activities for your child.
• Antibiotics before procedures. This includes dental work. This depends on whether your child has had a valve repair or replacement.
• Blood thinners (anticoagulants). These prevent blood clots from forming on a mechanical valve. Blood tests to check the blood thinners are also done.
• Possible repeat valve repair or replacement.

Talk with your child's doctor about what sports activities are safe.

Contact your child's doctor if you notice:

• Symptoms such as chest pain or trouble breathing that get worse.
• Dizziness or tiredness with physical activity.
• Symptoms of infection, such as fever or chills.

If your child has had a procedure, make sure to follow all instructions from the surgeon. And make sure to keep all follow-up appointments with your child's cardiologist and surgeon.

• Aortic stenosis means that a valve in your child's heart is too narrow or is blocked. This condition can be mild, moderate, or severe.
• Common symptoms are tiredness, trouble feeding and not enough weight gain, dizziness, shortness of breath, chest pain or discomfort, and a fast heartbeat.
• A pediatric cardiologist usually diagnoses and manages aortic stenosis.
• Several procedures are available to repair or replace the aortic valve.
• First-degree relatives of your child should talk with their doctors about the need for screening for aortic stenosis.
• A child with aortic stenosis should be checked often. Follow-up care is needed throughout their life.

Here are some tips to help you get the most from a visit to your child's doctor:

• Know the reason for the visit and what you want to happen.
• Before your visit, write down questions you want answered.
• At the visit, write down the name of a new diagnosis and any new medicines, treatments, or tests. Also write down any new instructions your doctor gives you for your child.
• Know why a new medicine or treatment is prescribed and how it will help your child. Also know what the side effects are.
• Ask if your child's condition can be treated in other ways.
• Know why a test or procedure is recommended and what the results could mean.
• Know what to expect if your child does not take the medicine or have the test or procedure.
• If your child has a follow-up appointment, write down the date, time, and purpose for that visit.
• Know how you can contact your child's doctor after office hours and on weekends and holidays. This is important if your child becomes ill and you have questions or need advice.