Mitral valve prolapse and coronary artery disease. Clinical, hemodynamic, and angiographic correlations.

Abstract

Among 95 patients with angina pectoris and angiographically documented coronary artery disease (CAD), prolapse of the scallops of the posterior leaflet of the mitral valve (PLMV) was noted in 30 patients. Left ventriculograms in the right anterior oblique (RAO) projection revealed isolated prolapse of the posteromedial commissural scallop (PMCS) in 12 patients and the anterolateral commissural scallop (ALCS) in two patients. Seven patients had prolapse of both PMCS and ALCS, three had prolapse of the PMCS and middle scallop (MS), and six had prolapse of all three scallops of the PLMV. Left ventricular dilatation with increase trabeculations was observed in 19 patients. Contractility determined in a quantitative fashion by segmental motion analysis was markedly impaired in 29 patients. None of the patients had angiographic evidence of mitral insufficiency. Left ventricular dysfunction was documented in 28 patients by either elevated left ventricular end-diastolic pressure (LVEDP), low cardiac index (CI) or decreased ejection fraction (EF). In two patients in whom left ventricular contractility improved after aortocoronary by pass, previously prolapsed scallops could not be identified in the postoperative ventriculogram. Prolapsed PLMV is a frequent angiographic finding in patients with angiographically observed CAD. Impaired contractility of the ventricular myocardium and papillary muscles, left ventricular dilatation, and hypertrophy appear to play a significant role in the pathogenesis of this abnormality through distortion of the directional axis of the papillary muscles, asynergic contraction of the related free wall of the left ventricle, and changes in the normal spatial alignment necessary for mitral valve closure. The syndrome of papillary muscle dysfunction in patients with coronary artery disease represents a wider clinical spectrom than previously described.