The human heart has 4 valves. The mitral valve connects the left atrium (LA) and the left ventricle (LV). The mitral valve opens during diastole to allow the blood flow from the LA to the LV. During ventricular systole, the mitral valve closes and prevents backflow to the LA. The normal function of the mitral valve depends on its 6 components, which are (1) the left atrial wall, (2) the annulus, (3) the leaflets, (4) the chordae tendineae, (5) the papillary muscles, and (6) the left ventricular wall (see the image below).
Components of the mitral valve apparatus.
Any congenital or acquired disorder of individual components can disturb the finely coordinated mechanisms of the mitral valve and result in an incompetent valve.
This article summarizes basic gross anatomy, microscopic anatomy, and pathophysiologic variants of the mitral valve disorders.