VALUE OF ACCELERATION FLOWS AND REGURGITANT JET DIRECTION BY COLOR DOPPLER FLOW MAPPING IN THE EVALUATION OF MITRAL-VALVE PROLAPSE

To clarify the role of color Doppler echocardiography in the evaluation of mitral valve prolapse we studied 49 consecutive patients in whom the sites of mitral valve prolapse were confirmed at the time of operation. The study group consisted of 22 patients with anterior leaflet prolapse, 24 patients with posterior leaflet prolapse, and three patients with multiple scallop prolapse (one patient with both anterior leaflet and middle scallop prolapse, and two patients with both medial and lateral scallop prolapse). Two-dimensional echocardiographic diagnosis of anterior leaflet prolapse was correct in all patients. The diagnosis of posterior leaflet prolapse by two-dimensional echocardiography, however, was mistaken as anterior leaflet prolapse in 16 (13 patients with medial scallop prolapse and three patients with lateral scallop prolapse) of the 24 patients with medial scallop prolapse and three patients with lateral scallop prolapse) of the 24 patients according to current diagnostic criteria for mitral valve prolapse. Eight patients with middle scallop prolapse were diagnosed correctly by two-dimensional echocardiography. Acceleration flows in the left ventricle were observed by color Doppler echocardiography in all 49 patients. The sites of acceleration flows detected by color Doppler echocardiography coincided with those of prolapse confirmed in all at the time of operation. There was a significant correlation between the maximum area of acceleration flow signals and severity of mitral regurgitation estimated by angiography. In the 13 patients with medial scallop prolapse and the three patients with lateral scallop prolapse, a regurgitant jet originated from a bulged portion of the posterior leaflet and was directed toward the opposite left atrial cavity to the bulged portion by short-axis images of color Doppler echocardiography. In the remaining 30 patients with single prolapse, a regurgitant jet again was directed toward the left atrial cavity opposite to the prolapsed scallop. In three patients with multiple scallop prolapse, it was difficult to determine the direction of the regurgitant jet by color Doppler echocardiography because of multiple regurgitant jets in the left atrium. In these three patients, however, two acceleration flows in the left ventricle were detected, and the sites of acceleration flows coincided with those of prolapse confirmed at the time of surgery. Thus, information on acceleration flows and direction of regurgitant jets detected by color Doppler echocardiography is useful in the detection of the site of mitral valve prolapse.