The Fluid Dynamics of Heart Valves: Experimental, Theoretical, and Computational Methods

Abstract

The function of the valves on the left side of the heart is reviewed in Figure I, which shows schematically the pressures, flows, and valve positions of the mitral (inflow) and aortic (outflow) valves of the left ventricle. Note that the cardiac cycle can be divided into two main parts according to whether the ventricular muscle is contracting (systole) or relaxing (dias­ tole). During systole, the mitral valve is closed, the aortic valve is open� and the left ventricle forms a common chamber with the aorta. During diastole, the valve configurations are reversed, and the left ventricle forms a common chamber with the left atrium. Note that the pressure difference across the open valve is very small, and that there is no backflow except for a spurt of brief duration associated with the closure movement of the valve. The valves themselves are thin membranous leaflets. To appreciate their remarkable anatomy, see the superb drawings of Netter (1969). Better still, dissect a fresh beef heart (available from wholesale meat markets and some retail stores).