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.
The mitral valve is also prone to a disease referred to as mitral valve prolapse. With mitral valve prolapse, the mitral valve bulges slightly back into the left atrium when it closes, allowing a small amount of blood to leak backward. Mitral Valve Insufficiency/Regurgitation.1  Overview: Mitral valve insufficiency/regurgitation is a disease in which the mitral valve does not close completely, causing blood to flow backward instead of forward through the valve. 2  Mitral valve insufficiency/regurgitation may develop in response to a number of conditions.itral Valve Regurgitation, Stenosis, and Prolapse. The mitral valve is referred to as atrioventricular valves because it is located between the left atria and the left ventricle.