What is mitral valve stenosis?
stenosis is a heart problem in which the
mitral valve doesn't open as wide as it should. The valve becomes stiff or scarred, or the valve flaps become partially joined
See a picture of
mitral valve stenosis .
Mitral valve stenosis can lead to
heart failure; a stroke; an infection in the heart (endocarditis);
or a fast, slow, or uneven heartbeat (arrhythmia). Fortunately, mitral valve stenosis can be treated.
Mitral valve stenosis is not common in
developed countries such as the United States, Canada, and western Europe.
How does the mitral valve work?
Your heart has
four chambers and four valves. The valves have flaps, or leaflets. The flaps
open and close to keep blood flowing in the proper direction through your
The mitral valve connects the heart's upper left chamber
(left atrium) to the lower left chamber (left ventricle). When the heart pumps,
blood forces the flaps open, and blood flows from the left atrium to the left
ventricle. Between heartbeats, the flaps close tightly so that blood does not
leak backward through the valve.
With mitral valve stenosis, not as
much blood can flow into the left ventricle. More blood stays in the left
atrium, and blood may back up into the lungs.
See a picture of the
heart and its chambers, valves, and blood flow .
See a picture of a
normal mitral valve .
What causes mitral valve stenosis?
cases of mitral valve stenosis are caused by
rheumatic fever. This fever results from an untreated
strep infection, most often
strep throat. But many people who have mitral valve
stenosis don't realize that they had rheumatic fever.