Mitral valve stenosis and heart failure

Heart failure is the most serious complication and the leading cause of death from mitral valve stenosis.

In mitral valve stenosis, the valve opening narrows, and the heart initially compensates by pumping harder. But eventually pressure builds in your left atrium as more and more force is needed to push blood across your narrowing mitral valve. This eventually stretches the atrium's walls, weakens the heart, and leads to heart failure.

A narrowed mitral valve may also not close properly and the valve may begin to leak, causing mitral valve regurgitation. The stenosis and regurgitation also causes pressure to build up in the lungs (pulmonary hypertension), which can lead to the pulmonic valve leaking (pulmonic regurgitation). When pulmonary hypertension occurs, it may lead to right-sided heart failure.

As fluid gathers within the heart and lungs, the heart must exert even greater force to pump blood to the body-further weakening the heart and causing even more fluid buildup-thereby creating a vicious cycle. Eventually the heart loses its ability to pump, resulting in heart failure and often death.