Aortic valve stenosis — or aortic stenosis — occurs when the heart's aortic valve narrows. This narrowing prevents the valve from opening fully, which reduces or blocks blood flow from your heart into the main artery to your body (aorta) and onward to the rest of your body.
When the blood flow through the aortic valve is reduced or blocked, your heart needs to work harder to pump blood to your body. Eventually, this extra work limits the amount of blood it can pump, and this can cause symptoms as well as possibly weaken your heart muscle.
Your treatment depends on the severity of your condition. You may need surgery to repair or replace the valve. Left untreated, aortic valve stenosis can lead to serious heart problems.
Aortic valve disease care at Mayo Clinic
Aortic valve stenosis ranges from mild to severe. Aortic valve stenosis signs and symptoms generally develop when narrowing of the valve is severe. Some people with aortic valve stenosis may not experience symptoms for many years. Signs and symptoms of aortic valve stenosis may include:
- Abnormal heart sound (heart murmur) heard through a stethoscope
- Chest pain (angina) or tightness with activity
- Feeling faint or dizzy or fainting with activity
- Shortness of breath, especially when you have been active
- Fatigue, especially during times of increased activity
- Heart palpitations — sensations of a rapid, fluttering heartbeat
- Not eating enough (mainly in children with aortic valve stenosis)
- Not gaining enough weight (mainly in children with aortic valve stenosis)
The heart-weakening effects of aortic valve stenosis may lead to heart failure. Heart failure signs and symptoms include fatigue, shortness of breath, and swollen ankles and feet.
When to see a doctor
If you have a heart murmur, your doctor may recommend that you visit a cardiologist. If you develop any symptoms that may suggest aortic valve stenosis, see your doctor.
Chambers and valves of the heart
A normal heart has two upper (receiving) and two lower (pumping) chambers. The upper chambers, the right and left atria, receive incoming blood. The lower chambers, the more muscular right and left ventricles, pump blood out of your heart. The heart valves, which keep blood flowing in the correct direction, are gates at the chamber openings (for the tricuspid and mitral valves) and exits (for the pulmonary and aortic valves).
Aortic valve stenosis
In aortic valve stenosis, there is progressive narrowing of the aortic valve opening over time (top row), which results in increased pressure within the heart and reduced capacity to pump blood to the body. This is similar to attaching smaller and smaller nozzles to the end of a garden hose (bottom row). The narrowing from the nozzle slows the forward flow of water and results in progressive pressure buildup within the garden hose.
Aortic valve stenosis
Aortic valve stenosis is a defect that narrows or obstructs the aortic valve opening, making it difficult for the heart to pump blood into the aorta. This may not have symptoms initially, but it can worsen over time. Typically the aortic valve has three cusps (tricuspid aortic valve), but some people are born with an aortic valve that has two cusps (bicuspid aortic valve).
Your heart has four valves that keep blood flowing in the correct direction. These valves include the mitral valve, tricuspid valve, pulmonary valve and aortic valve. Each valve has flaps (cusps or leaflets) that open and close once during each heartbeat. Sometimes, the valves don't open or close properly, disrupting the blood flow through your heart and potentially impairing the ability to pump blood to your body.
In aortic valve stenosis, the aortic valve between the lower left heart chamber (left ventricle) and the main artery that delivers blood from the heart to the body (aorta) is narrowed (stenosis).
When the aortic valve is narrowed, the left ventricle has to work harder to pump a sufficient amount of blood into the aorta and onward to the rest of your body. This can cause the left ventricle to thicken and enlarge. Eventually the extra work of the heart can weaken the left ventricle and your heart overall, and it can ultimately lead to heart failure and other problems.
Aortic valve stenosis can occur due to many causes, including:
Congenital heart defect. The aortic valve consists of three tightly fitting, triangular-shaped flaps of tissue called cusps. Some children are born with an aortic valve that has only two (bicuspid) cusps instead of three. People may also be born with one (unicuspid) or four (quadricuspid) cusps, but these are rare.
This defect may not cause any problems until adulthood, at which time the valve may begin to narrow or leak and may need to be repaired or replaced.
Having a congenitally abnormal aortic valve requires regular evaluation by a doctor to watch for signs of valve problems. In most cases, doctors don't know why a heart valve fails to develop properly, so it isn't something you could have prevented.
Calcium buildup on the valve. With age, heart valves may accumulate deposits of calcium (aortic valve calcification). Calcium is a mineral found in your blood. As blood repeatedly flows over the aortic valve, deposits of calcium can build up on the valve's cusps. These calcium deposits aren't linked to taking calcium tablets or drinking calcium-fortified drinks.
These deposits may never cause any problems. However, in some people — particularly those with a congenitally abnormal aortic valve, such as a bicuspid aortic valve — calcium deposits result in stiffening of the cusps of the valve. This stiffening narrows the aortic valve and can occur at a younger age.
However, aortic valve stenosis that is related to increasing age and the buildup of calcium deposits on the aortic valve is most common in older people. It usually doesn't cause symptoms until ages 70 or 80.
Rheumatic fever. A complication of strep throat infection, rheumatic fever may result in scar tissue forming on the aortic valve. Scar tissue alone can narrow the aortic valve and lead to aortic valve stenosis. Scar tissue can also create a rough surface on which calcium deposits can collect, contributing to aortic valve stenosis later in life.
Rheumatic fever may damage more than one heart valve, and in more than one way. A damaged heart valve may not open fully or close fully — or both. While rheumatic fever is rare in the United States, some older adults had rheumatic fever as children.
Risk factors of aortic valve stenosis include:
- Older age
- Certain heart conditions present at birth (congenital heart disease) such as a bicuspid aortic valve
- History of infections that can affect the heart
- Having cardiovascular risk factors, such as diabetes, high cholesterol and high blood pressure
- Chronic kidney disease
- History of radiation therapy to the chest
Aortic valve stenosis can cause complications, including:
- Heart failure
- Blood clots
- Heart rhythm abnormalities (arrhythmias)
- Infections that affect the heart, such as endocarditis
Some possible ways to prevent aortic valve stenosis include:
- Taking steps to prevent rheumatic fever. You can do this by making sure you see your doctor when you have a sore throat. Untreated strep throat can develop into rheumatic fever. Fortunately, strep throat can usually be easily treated with antibiotics. Rheumatic fever is more common in children and young adults.
- Addressing risk factors for coronary artery disease. These include high blood pressure, obesity and high cholesterol levels. These factors may be linked to aortic valve stenosis, so it's a good idea to keep your weight, blood pressure and cholesterol levels under control if you have aortic valve stenosis.
- Taking care of your teeth and gums. There may be a link between infected gums (gingivitis) and infected heart tissue (endocarditis). Inflammation of heart tissue caused by infection can narrow arteries and aggravate aortic valve stenosis.
Once you know that you have aortic valve stenosis, your doctor may recommend that you limit strenuous activity to avoid overworking your heart.