The SI unit for pressure is the pascal (Pa), equal to one newton per square metre (N/m 2 or kgÂ·m â1 Â·s â2). This name for the unit was added in 1971; before that, pressure in SI was expressed simply in newtons per square metre.
A leaking mitral valve allows blood to flow in two directions during the contraction. Some blood flows from the ventricle through the aortic valve â as it should â and some blood flows back into the atrium. A leaking (or regurgitant) aortic valve allows blood to flow in two directions.
In mitral valve regurgitation, the mitral valve doesn't close tightly. With each heartbeat, some blood from the left ventricle flows backward into the left atrium instead of moving forward into the aorta. This essentially means that the heart pulls blood backward.ossible causes of mitral valve regurgitation include: 1  Mitral valve prolapse. 2  In this condition, the leaflets and tendon-like cords supporting the mitral valve weaken and stretch so that with each contraction of the left ventricle, the valve leaflets bulge (prolapse) into the left atrium.