The Echocardiographic Determination of Mitral Valve Opening and Closure

The ability of the echocardiogram to define mitral valve opening and closure was assessed by simultaneously recording the echocardiogram of the anterior leaflet (ECHO) with intracardiac pressures, aortic second sound, and ECG on 38 occasions in 14 patients undergoing cardiac catheterization. Hemodynamic opening and closure were defined by intersection of the pulmonary wedge and left ventricular pressures and the onset of left ventricular systole. The onset of the most rapid anterior motion (D') in early diastole and termination of the last rapid posterior movement in end diastole (CO) were used as echocardiographic markers of mitral valve opening and closure. Intervals measured included: the isovolumic relaxation period (IRP) from A2 to either hemodynamic (IRPH) or echocardiographic (IRPE) opening; the Q to closure interval (QCI) from the Q wave to either hemodynamic (QCIH) or echocardiographic (QCIE) closure; and diastolic filling period (DFP), either hemodynamic (DFPH) or echocardiographic (DFPE). The following significant (P < .01) regression equations resulted: IRPE = (.97) IRPH + 30 (SE\s 8 msec) r .89; QCIE = (.68) QCIH + 37 (SEM ± 7 msec) r = .71; DFPE = (.98) DFPH + 10 (SEN\ 18 msec) r .98. Thus hemodynamic markers of opening and closure systematically precede echocardiographic markers of opening (D') and closure (CO) and the diastolic filling periods are equal within 10 msec. It is concluded that the echocardiogram of the anterior leaflet is a reliable indicator of hemodynamic markers of opening and closure of the mitral valve in man and is useful in the noninvasive determination of certain systolic and diastolic time intervals.