Aortic Stenosis

Signs and Symptoms

Aortic stenosis is when the valve between the heart and aorta is deformed and too narrow to allow healthy blood flow. The aorta is the blood vessel that carries blood from the heart to branch arteries throughout the body.

The valves in the heart are like little one-way doors that allow blood to flow in the appropriate direction. A healthy aortic valve is made up of three flaps called leaflets that open and close together. When oxygenated blood leaves the lungs, it goes into the left side of the heart and exits into the aorta.

When the aortic valve is deformed, blood may "back-up" into the heart and lungs. Aortic stenosis can be a congenital condition although it also can be caused by other conditions. At one time, it often was associated with childhood rheumatic fever, which has become less common.

There are three types of aortic stenosis:

• Valvar, in which the valve opening has only one or two leaflets
  instead of the three it should have.
• Subaortic obstruction is a narrowing just below the valve.
• Supra-valvar obstruction is a narrowing just above the valve.

Each of these can occur independently or in combination. Aortic stenosis also may occur with other heart defects.

Critical aortic stenosis occurs when a baby is born with an extremely narrow aortic valve, which will result in death if not treated quickly. Severe obstruction to blood flow results in left heart failure and lung congestion causing shortness of breath. These babies also may experience fainting, called syncope. They often have a low blood pressure, and can be misdiagnosed as having shock due to sepsis.

Symptoms of aortic stenosis often don't appear until middle age or later. It is rare in infancy, occurring in only about a third of 1 percent of live births. It is 16th in ranking of serious infant heart conditions but is the second most common congenital disease in middle age. Aortic stenosis can be mild, moderate or critical.

Symptoms in older people can range from none to chest pain at rest, fatigue, inability to exercise and dizziness.

Diagnosis

Because there may be no obvious symptoms, the first indication of aortic stenosis is often a heart murmur, an extra sound the doctor hears during a chest examination. Aortic stenosis evaluation includes:

• Echocardiogram
• Electrocardiogram (ECG or EKG)
• Exercise test

Treatment

In babies, surgical treatment is a valvotomy, a procedure that splits the deformed valve leaflets to enlarge the opening without having to replace the valve. However, this procedure is successful only if the aortic valve is still thin enough to be manipulated. Stenosis eventually causes the valves to stiffen. Another surgery may be required later in life to further repair or replace the valve.

Children may be treated with a balloon valvoplasty, a non-surgical procedure in which a catheter -- a thin, flexible, plastic tube -- is inserted into the heart via blood vessels from the leg. A balloon at the tip of the catheter is inserted into the narrow opening in the valve and then inflated to stretch the valve opening and separate the valve leaflets.

In adults with severe stenosis, treatment is more likely to include surgical replacement with either a manufactured valve or a valve from another human. Another surgical repair is removing obstructive tissue, which may be done in conjunction with valve replacement.

Patients with aortic stenosis need preventive antibiotics to avoid heart infections during surgery or dental work. People with mild stenosis usually don't require treatment besides antibiotics. Medications may be used to control symptoms such as high blood pressure or heart rhythm problems, but don't control the stenosis itself.