leaf scar. (botany). A mark on a stem, formed by secretion of suberin and a gumlike substance, showing where a leaf has abscised. 1  Facebook. 2  Twitter.
Mitral valve regurgitation means that one of the valves in your heart-the mitral valve-is letting blood leak backward into the heart.Heart valves work like one-way gates, helping blood flow in one direction between heart chambers or in and out of the heart. The mitral valve is on the left side of your heart.It lets blood flow from the upper to the lower heart chamber. See a picture of mitral valve regurgitation.When the mitral valve is damaged-for example, by an infection-it may no longer close tightly.This lets blood leak backward, or regurgitate, into the upper chamber.t lets blood flow from the upper to the lower heart chamber. See a picture of mitral valve regurgitation. When the mitral valve is damaged-for example, by an infection-it may no longer close tightly. This lets blood leak backward, or regurgitate, into the upper chamber.
Mitral valve prolapse and regurgitation. The mitral valve separates the two chambers (atrium and ventricle) of the left side of the heart. In mitral valve prolapse, the leaflets of the mitral valve bulge (prolapse) into the left atrium like a parachute during the heart's contraction.itral valve regurgitation causes. Mitral valve regurgitation is classified as primary and secondary. Primary mitral valve regurgitation is caused by an abnormality in the mitral valve. Secondary mitral valve regurgitation is caused by an abnormality in the left ventricle of the heart.