M-mode echocardiogram of mitral valve prolapse

The M-mode echocardiograms and phonocardiograms are from three patients with mitral prolapse. In all three examples, the valve leaflets are thickened. In panel A, there is posterior displacement of the C-D segment that begins in early systole and persists throughout (pansystolic prolapse). In panels B and C, the prolapse begins roughly in mid-systole (late or mid-systolic prolapse). The phonocardiographic findings are not predicted by the morphologic appearance. In particular, the pansystolic prolapse in panel A has only a click (arrow) and no murmur, the example in panel B has a late systolic murmur (arrow) and no click, and the example panel C has both a click (CL) and a late systolic murmur (LSM).