Left ventricular function in mitral stenosis

The effects of isometric exercise on left ventricular performance were studied during cardiac catheterization in six patients with mitral stenosis and six patients without significant cardiac disease. Quantitative analyses of left ventricular cineangiograms were completed to correlate changes with the findings during exercise. During exercise, left ventricular function curves were abnormal in five of the six patients with mitral stenosis. In addition, ejection fractions were significantly lower in the group with mitral stenosis as compared with the normal subjects. The lower ejection fractions in the patient with mitral stenosis were due to localized abnormalities in the posterobasal and anterior left ventricular walls. It is concluded that left ventricular function is abnormal in mitral stenosis due to localized wall motion abnormalities, which are probably due to fibrosis near or in the papillary muscles.