Angiographic-echocardiographic correlation in mitral valve prolapse

Although mitral valve prolapse is easily identified with echocardiography, the angiographic diagnosis has been poorly understood. To determine relative specificity and sensitivity of recently established radiologic diagnostic criteria, prospective comparison of left ventriculograms with echocardiograms and clinical observations in patients undergoing routine cardiac catheterization from 1975 to 1977 and retrospective review of earlier catheterization data have been performed. Four types of normal mitral valve configurations were determined during protodiastole in the right anterior oblique (RAO) projection of left ventriculograms by identifying the fulcrum, the point of attachment of the mitral leaflets to the annulus fibrosus, and the fornix, that part of the left ventricular wall between the fulcrum and papillary muscles. Prolapse was present when mitral leaflet tissue extended inferiorly and posteriorly to the fulcrum during systole. Angiographic prolapse of the posteromedial commissural scallop of the posterior leaflet was diagnosed in RAO ventriculograms in 21 patients, approximately 1.9 per cent of the adult catheterization population. All of these patients also had positive echocardiograms. Three other patients had positive echocardiograms despite normal ventriculograms. In one of these three, isolated prolapse of the middle commissural scallop of the posterior leaflet was present. No patient with a normal mitral valve echocardiogram had an abnormal ventriculogram. The proposed angiographic criteria for mitral valve prolapse have eliminated false-positive diagnoses, and permitted accurate identification in approximately 88 per cent of cases. Improved imaging and additional left ventriculographic projections will probably improve sensitivity. The frequencies of angiographic, echocardiogrphic, and clinical diagnoses of mitral valve prolapse are not significantly different.