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What is aortic valve stenosis?

Aortic valve stenosis occurs when the aortic valve, which allows blood to flow from the heart to the body, does not open properly. When the valve is narrowed or stiff, blood has trouble leaving the heart. This makes the left ventricle work harder to pump blood past the blockage which can lead to increased pressure inside the heart.

Some people with aortic valve disease also have aortic valve insufficiency, also called regurgitation. This happens when the valve does not close tightly. Blood leaks backward into the left ventricle after it has been pumped out.

Congenital aortic valve stenosis happens when the valve does not form normally before birth. A healthy aortic valve has three thin, flexible leaflets (cusps). In congenital aortic valve stenosis, the valve may have two leaflets (bicuspid) or one leaflet (unicuspid). They are often thicker and stiffer and do not open or close as they should.

The heart has four chambers. The upper two chambers are the atria, and the lower two are the ventricles (Figure A). The chambers are separated by a wall of tissue called the septum. Blood is pumped through the chambers, aided by four heart valves. The valves open and close to let the blood flow in only one direction.

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What causes aortic valve stenosis?

In most children, the cause of this common heart defect isn’t known. Some children with aortic valve stenosis may also have other heart defects.

This condition is more common with aging. Calcium buildup and scarring can damage the valve and restrict blood flow.

How does aortic valve stenosis affect the heart?

In aortic valve stenosis, the pressure is much higher than normal in the left pumping chamber (left ventricle). The heart must work harder to pump blood out into the body’s arteries. Over time, this can cause thickening (hypertrophy) and damage the overworked heart muscle.

If the valve also leaks (insufficiency), the left ventricle must pump not only the normal amount of blood but also the blood that leaks back into the chamber between heartbeats. This extra work can cause the left ventricle to enlarge (dilate) and may further strain the heart muscle.

Some infants are born with severely narrowed aortic valves and need early treatment. However, most bicuspid aortic valves function normally for many years — sometimes a lifetime.

What are the symptoms of aortic valve stenosis?

Mild obstruction usually causes no symptoms. When stenosis is severe, symptoms may include:

• Shortness of breath with physical activity
• Tiring easily
• Dizziness with physical activity
• Fainting

The condition is often detected by a heart murmur. In some people, especially those with congenital valve problems, an extra sound called an ejection click may also be heard. As the valve opening becomes more severely narrowed, symptoms become more common. The most common symptom of an obstructed or leaky aortic valve is shortness of breath with exertion. This usually develops slowly over time. Some people may simply feel out of shape.

Aortic valve stenosis in children: What families need to know

Some children primarily have narrowing (stenosis), others have leakage (insufficiency) and some have both.

How can the aortic valve be treated?

The valve can be treated to improve obstruction or leakage but usually cannot restored to completely normal structure or function. Children with aortic valve stenosis will need treatment when the pressure in the left ventricle is high due to the narrowed valve. Even if they have no symptoms, they need treatment. In most children, the obstruction can be relieved during cardiac catheterization by balloon valvuloplasty (also called balloon valvotomy). In this procedure, a catheter with a balloon is placed across the aortic valve. The balloon is briefly inflated to widen the valve opening by separating or stretching the valve leaflets.

Some children with aortic valve stenosis may need surgery. The surgeon may be able to enlarge the valve opening if it’s too small. Some valve leakage is likely to develop or increase after a balloon or surgical treatment for obstruction.

If your child’s aortic valve no longer responds to valvotomy or has become severely insufficient (leaky), a valve replacement is usually needed. The aortic valve can be surgically replaced in one of three ways:

• In the Ross procedure, the abnormal aortic valve is removed and replaced by the child’s own pulmonary valve. Then, the pulmonary valve is replaced with a preserved donor pulmonary valve.
• The aortic valve is replaced with a preserved donor valve.
• The aortic valve is replaced with a mechanical valve.

Each option has advantages and disadvantages. Discuss them with your child’s pediatric cardiologist, cardiac surgeon or both.

Which activities can my child do?

If the aortic valve is abnormally formed but has no important obstruction or leak, your child may be able to participate in normal activities without increased risk. Some children with obstruction, valve leakage or heart muscle changes may need to limit certain types or levels of exercise. Your child’s pediatric cardiologist should advise you about activity limitations, if needed.

What will my child need in the future?

Children with aortic valve stenosis need lifelong medical follow-up. Your child’s pediatric cardiologist will periodically check for problems such as worsening of the obstruction or leak. Even mild stenosis may worsen over time. Also, balloon or surgical relief of a blockage is sometimes incomplete. After treatment, the valve may still work in a mildly abnormal way.

Can endocarditis be prevented?

Children with aortic stenosis or aortic insufficiency have an increased risk of developing endocarditis, an infection in the valve. Children with certain high-risk heart conditions, including those with prosthetic heart valves, prior infective endocarditis or specific congenital heart defects, may need antibiotics before certain dental procedures. Your child’s cardiologist will determine if this is needed. It is also important for children to practice good dental care to lower their risk of endocarditis.

Aortic valve stenosis in adults: What to expect

If aortic valve stenosis or regurgitation is still present, should it be repaired in adulthood?

When the aortic valve becomes too obstructed or leaky, the valve must be repaired or replaced.

Repair of the valve can be done either in:

• The catheterization lab (called interventional or therapeutic catheterization) using a balloon to force the leaflets open
• The operating room by open-heart surgery

Some valve leakage is likely to develop after either approach. Some people will have had one or both procedures as an infant or child.

Replacing the valve may require open-heart surgery. Some adults may be candidates for catheter-based valve replacement. In most adults, when the valve is no longer working properly, especially when the valve is heavily calcified, replacement is preferred over repair. Deciding when to perform aortic valve surgery and which type of valve to use are complex decisions made by you and your heart care team. Your aortic valve can be replaced using one of the following options:

• A mechanical valve made of metal, which is durable but requires lifelong anticoagulation medication
• A valve made from biological tissue, which requires no anticoagulation medication but may not last as long and may need to be replaced later
• A homograft or valve from a donated human heart and preserved in special solutions may be used. Homograft valves require no anti-clotting medication  but may not last as long. This can be a good option when a portion of the aorta is also being replaced.
• In the Ross procedure, the aortic valve is replaced with the patient’s own pulmonary valve. The pulmonary valve is replaced with a donor valve. This option requires no anti-clotting medication and may provide a more durable aortic valve. Yet the new pulmonary valve will likely need to be replaced later with another surgery.

You should discuss these options with your cardiologist and cardiac surgeon to determine the best choice for your situation.

Sometimes narrowing is present just below the aortic valve, with or without affecting the valve itself. In these cases, a more complex operation, often called a Konno procedure, may be needed to enlarge the part of the left ventricle that leads to the aortic valve. The problem may recur years later, requiring more surgery.

Ongoing care for aortic valve stenosis

Medical

Regular checkups are important for everyone with an aortic valve defect. This condition can change over time. Even after successful treatment, ongoing care is needed. The severity of the valve problem will determine:

• Frequency of checkups
• Tests needed
• Which medications are needed

It’s important to work with a cardiologist who has experience caring for adults with congenital heart disease.

Activity restrictions

For some people with a severely obstructed aortic valve, rigorous activity may not be advised. Activity limits should be discussed with a cardiologist.

Endocarditis prevention

People with even mildly abnormal aortic valves are at increased risk for infective endocarditis. Good oral hygiene and regular dental care are important for prevention. Antibiotics before dental procedures are not routinely recommended but may be needed for some people, such as those with a prosthetic valve.

Possible complications

Symptoms of aortic valve stenosis or aortic valve insufficiency usually happen only when the condition is severe. Symptoms include:

• Shortness of breath
• Exercise intolerance
• Dizziness
• Chest pain
• Occasional abnormal heart rhythms

Some patients, especially those with a bicuspid aortic valve, may develop enlargement of the aorta over time. This can sometimes require surgery.

Pregnancy

The risk from pregnancy depends on how severely the valve is obstructed or how much it’s leaking.

If you have mild or moderate stenosis and your left heart muscle (ventricle) is functioning normally, you can often have a safe pregnancy. Still, you need medical supervision throughout the pregnancy. If symptoms occur during pregnancy and they can’t be controlled by medication, balloon valvotomy may be considered.

If your stenosis is severe and you have symptoms, avoid conception until your heart valve has been repaired or replaced. If you’re considering pregnancy and have aortic valve stenosis, you should be evaluated by specialists experienced in managing heart disease during pregnancy.

Aortic regurgitation is usually better tolerated during pregnancy. But if the regurgitation has weakened the heart muscle and signs of heart failure are present before pregnancy, the risk posed by pregnancy is higher.

Patients with a mechanical heart valve often take warfarin, which can pose risks to the fetus. Other anticoagulant strategies may be needed. Some women with aortic regurgitation and high blood pressure or heart muscle changes may be taking medications such as ACE inhibitors (including lisinopril or enalapril). These medications are harmful to a developing fetus and should be changed before conception.

Talk with your health care professional before you plan to become pregnant.

When is another surgery needed?

If you have already had aortic valve surgery, you may need another procedure in the future. This can depend on the type of valve used and how your heart and aorta change over time. No surgical repair lasts forever, so regular follow-up with a cardiologist familiar with your aortic valve and aorta is recommended.