The mitral valve controls blood flow between the upper and lower chambers on the left side of the heart. In mitral valve stenosis, the valve narrows, restricting blood flow through the heart. In mitral valve regurgitation, the valve does not close completely, allowing blood to flow backward through the valve and possibly into the lungs. As a result of either condition, the heart muscle may have to pump harder and blood flow to the body may decrease, which can ultimately lead to heart failure.
Mitral valve stenosis in adults may occur as a result of rheumatic fever (often associated with untreated strep throat or scarlet fever), the formation of calcium deposits around the mitral valve, radiation treatment in the chest and the use of some medications. Mitral valve regurgitation often occurs with age. However, the condition can also develop or worsen as a result of rheumatic fever, atherosclerosis (narrowing of the arteries) or endocarditis (inflammation of the lining inside the heart), among other conditions. Common symptoms of mitral valve stenosis may include chest pain (often increasing with activity), difficulty breathing, fatigue, swelling of the feet or ankles, cough, shortness of breath and palpitations (rapid, noticeable heart beats).