How does mitral stenosis affect the heart?

Depends: Mitral stenosis(ms) can cause a variety of symptoms depending on severity. Severe MS can cause left atrial enlargement leading to afib and since the mv is the "door "to the left ventricle there is decrease in cardiac out put.Pressure builds up behind it and back in to the lungs and can cause congestive heart failure.Ms pts can get their valve replaced and reverse many of these if done early enough.

Mitral valve: Valves are like doors, they have to open and close. Mitral stenosis is when the mitral valve doesn't open enough. This causes shortness of breath by forcing lung pressure up. Repair or replacement of the symptomatic valve improves the problem, if surgery possible, medical therapy less effective long term.