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.
The frequency of mitral regurgitation was. increased in older subjects, whichcould potentially. be a function of valve degeneration. However, the. incidence ofdetectable valve regurgitation also var-. ied in other surprising ways. Thus, regurgitant flow. signals from the pulmonary and tricuspid valves. were detectable with decreasing incidence by color. flow mapping in the older age group. The authors.