The effect of congesting cuffs on the echo-phonocardiographic findings in mitral valve prolapse.

Changes in left ventricular volume appear to be important in changing the timing and duration of mitral valve prolapse. In this study, simultaneous phonocardiograms and echocardiograms were recorded in 16 patients with late systolic mitral valve prolapse before and after the inflation of congesting cuffs (tourniquets) on the upper and lower extremities. The tourniquet application, known to reduce the venous return, caused a statistically significant movement of the phonocardiographic recorded click toward the first heart sound, associated with reduction of the echocardiographic left and right ventricular and left atrial dimensions. These findings confirm the relationship between the mitral valve prolapse and left ventricular dimension and suggest that a decrease in left ventricular volume is a tenable explanation for the earlier onset of prolapse.