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Mitral stenosis

• Overview
• Symptoms
• Treatment
• Prevention

Definition:

Mitral stenosis is a narrowing or blockage of the opening of the mitral valve, which separates the upper and lower chambers on the left side of the heart. This prevents proper blood flow from moving between the left atrium (upper chamber of the heart) and ventricle (lower chamber of the heart).

Alternative Names:

Mitral valve obstruction

Causes, incidence, and risk factors:

Mitral stenosis is a heart valve disorder. Symptoms usually develop between the ages of 20 and 50. It most commonly occurs in people who have had rheumatic fever . Since rheumatic fever rates are declining in the United States, the incidence of mitral stenosis is also decreasing. Only rarely do other disorders cause mitral stenosis.

The condition may be present from birth (congenital), but it seldom occurs as a single defect. Congenital mitral stenosis is more often part of a complex heart deformity.

Mitral stenosis prevents the valve from opening properly and blocks the blood flow from the left atrium to the left ventricle. As the valve area becomes smaller, less blood flows forward to the body. The atrium swells as pressure builds up and blood may flow back into the lungs, resulting in pulmonary edema (fluid in the lung tissue).

The main risk factor for mitral stenosis is a history of rheumatic fever. Symptoms may begin with an episode of atrial fibrillation or may be triggered by pregnancy or other stress on the body such as infection (in the heart, lungs, etc.) or other cardiac disorders.

• Review Date: 5/30/2006
• Reviewed By: Alan Berger, MD, Assistant Professor, Divisions of Cardiology and Epidemiology, University of Minnesota, Minneapolis, MN. Review provided by VeriMed Healthcare Network.

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