The heart is structured with two forkamre and two heart chambers (see cardiac structure). Between each pre arteries and sit there a so-called heart valve. Its function is to allow a flow of blood from pre to the arteries when the pre emptied, but prevent a return of blood to pre when the heart chamber is pulling together and run blood from the heart.
How the blood run out of the two heart chambers, respectively lung and circulatory hovedpulsåren, who also sits flaps to ensure that blood does not spill back into the heart. The fold between right and the arteries is calledtrikuspidalklappen, And matched in the left half of the heartmitralklappen. Fold to lung circuit statespulmonalklappenAnd respect for hovedpulsåren, aorta, sitsaortaklappen. There can be various diseases of the heart valves. For example. infection and rheumatic fever. These can cause damage to the flaps. The injury could mean that clamshell a narrow, so the blood's harder to get through. That makes it part of the heart, which must pump blood, becomes congested. The flip-called stenosis. There may also be the case that flip can not close sufficiently close longer, and the blood runs back where it came from. The burden on the heart. The mode is called flip-insufficiency. Stenosis and insufficiency may occur in the same fold simultaneously. It is most commonly aortic and mitralklappen that are affected. (See cardiac diseases). A damaged heart valve may also be caused by a congenital heart defect or older.
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