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Aortic Stenosis


The Manual's Editorial Staff

Last full review/revision Feb 2021| Content last modified Feb 2021
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What is aortic stenosis?

The aorta is the main artery that carries blood away from your heart to the rest of your body.

Four heart valves control how blood flows in and out of your heart. The valves are like one-way doors that keep blood flowing in the right direction. 

The aortic valve is between your heart and aorta. This valve opens into the aorta to let blood out of your heart. The valve closes to keep blood from running back into your heart.

Aortic stenosis is when your aortic valve won't open all the way. The narrowed valve makes it hard for your heart to pump out blood.

  • Certain disorders can cause the flaps on the aortic valve to get stiff and thick

  • Causes of aortic stenosis include birth defects or sometimes just getting older

  • The narrower the valve, the harder your heart has to work to pump out enough blood

  • When the valve is very narrow, your heart has to pump so hard that you develop heart failure

  • You may have chest tightness, feel short of breath, or pass out

  • Doctors can hear a heart murmur through a stethoscope and do echocardiography to diagnose aortic stenosis

  • Doctors may need to replace your aortic valve

What causes aortic stenosis?

In people younger than 70, the most common cause is a birth defect of the aortic valve.

In people over 70, the most common cause is thickening of the valve cusps (called aortic sclerosis).

The most common cause in the developing world is untreated rheumatic fever. Rheumatic fever is a rare complication of untreated strep throat that children can get.

What are the symptoms of aortic stenosis?

Children who have aortic stenosis caused by a birth defect may not have symptoms until they become adults.

Symptoms of aortic stenosis include:

  • Chest tightness when you exercise

  • Feeling tired and short of breath

  • Fainting without any warning signs such as dizziness or light-headedness

How can doctors tell if I have aortic stenosis?

Doctors suspect aortic stenosis by listening to your heart with a stethoscope. Doctors use echocardiography (an ultrasound of your heart) to find out how bad the stenosis is.

If you have aortic stenosis but don't have symptoms, doctors often do a stress test.

If the stress test shows a problem or if you have symptoms, the doctors will do cardiac catheterization to find out if you have coronary artery disease as well as aortic stenosis. That's because if you need surgery for aortic stenosis, doctors will also fix your coronary arteries at the same time. 

How do doctors treat aortic stenosis?

If you’re an adult with aortic stenosis but you don’t have symptoms, you should:

  • See your doctor regularly

  • Avoid overly stressful exercise

  • Have an echocardiography (an ultrasound of your heart) every now and then

If you have symptoms or if your left ventricle begins to fail, doctors will do surgery to replace your aortic valve with:

  • A plastic, mechanical valve

  • A valve from a pig or cow heart (bioprosthetic valve)

If you're very old and sick or there are other reasons why heart surgery would be too risky, doctors may replace your aortic valve during cardiac catheterization. But heart surgery is better if you're able to tolerate it.

If you get a mechanical valve, you'll need to take blood-thinning medicine for the rest of your life, but the valve may last several decades. If you get a bioprosthetic valve, you'll need to take the blood-thinning medicine for only a few months, but the valve will only last 10 to 12 years.

Children and young adults born with a problem in their valve may have a procedure called balloon valvotomy. The doctor inserts a thin, hollow tube (catheter) through a vein or artery into your heart. The doctor inflates a balloon on the tip of the catheter. The balloon pushes the valve open. Balloon valvotomy doesn't work very well for older people.

People with damaged or replaced valves sometimes need antibiotics to prevent heart valve infection, such as when they:

  • Get dental work

  • Have certain medical procedures

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