Definition

Aortic stenosis (AS) is a narrowing of the aortic valve opening. This valve controls the flow of blood from the heart to a large artery called the aorta. This artery carries blood from the heart to the rest of body.

AS makes it difficult for blood to flow out of the heart. It can decrease the amount of blood that goes to the body and cause a back-up of blood into the heart. This back-up can increase pressure in the heart and lungs. AS can range from mild to severe.

Causes

The aortic valve has 3 flaps that should open and close smoothly. AS is caused by a defect or damage to these flaps. Common causes include:

• A birth defect of the aortic valve, where the valve has 2 parts (cusps) instead of 3
• A 2-part aortic valve that becomes stenotic with progressive wear and tear
• An aortic valve that has only 1 cusp or has stenosis from birth
• Progressive hardening of the valve and calcium build-up associated with aging
• Scarring of the aortic valve caused by rheumatic fever—rare

Risk Factors

This condition is more common in men.

Factors that may increase the risk of AS include:

• Family members with heart disease that affects the valves
• History of rheumatic fever
• High blood pressure
• High cholesterol
• Diabetes
• Smoking

Symptoms

AS does not always produce symptoms. If symptoms do occur, they may include:

• Extreme fatigue after exercise or exertion
• Fainting with exercise or exertion
• Pain, squeezing, pressure, or tightness of the chest usually occurring with exertion
• Rapid or irregular heartbeat
• Shortness of breath
• Light-headedness with exertion
• Neurological symptoms of a stroke or transient ischemic attack

In rare cases, AS can cause abnormal heart rhythms or sudden death with no previous symptoms.

Diagnosis

The doctor will ask about your symptoms and past health. A physical exam will be done. The doctor may be alerted to AS by the following:

• Abnormal chest sounds such as a heart murmur or clicking sound
• Noticeable chest heave or vibration when the doctor's hand is held over your heart

Images may need to be taken of your chest. This can be done with:

• Chest x-ray
• Echocardiogram
• Cardiac catheterization

Treatment

If you have mild AS, your condition will be monitored, but you may not need immediate treatment.

If you have more severe AS:

• Your doctor may advise you to avoid strenuous physical activity.
• You may be given medicine to decrease pressure on the heart and help prevent heart failure.
• Surgery may be needed to repair the valve.

Surgery

Surgical options include:

• Balloon valvuloplasty—A balloon device is passed through the arteries to open or enlarge the stenotic aortic valve. This may provide temporary relief of symptoms. But since the valve can become blocked again, this treatment is not a permanent solution.
• Aortic valve replacement—Open surgery to replace the aortic valve. It may be replaced with a donor valve, tissue valve (from animal tissue), or a manufactured valve.
• Transcatheter aortic valve replacement (TAVR)—Minimally invasive surgery to replace the aortic valve. A small incision is made in the leg or chest. A wire is passed through the incision to the heart. The replacement valve is sent through the wire and is placed within the original valve.

Aortic Valve Replacement—Mechanical and Bioprosthetic Valve Shown Copyright © Nucleus Medical Media, Inc.

Prevention

AS cannot be prevented.