Analysis of the Mitral Coaptation Zone in Normal and Functional Regurgitant Valves

Mitral valve leaflet CL is asymmetric in normal valves, with anterior dominance. Functional mitral regurgitation is associated with a relocated coaptation zone, regional changes, and diminished coaptation. These data suggest an “anterior leaflet reserve.” Posterior movement of the coaptation line compensates for annular dilation and presumed left ventricular enlargement in order to maintain competency until inadequate anterior leaflet CL occurs.