[Left ventricular function in pure mitral stenosis. Hemodynamic echocardiographic study]. / La función ventricular izquierda en la estenosis mitral pura. Estudio ecocardiográfico hemodinámico.

We studied the left ventricular performance in 40 patients with pure mitral stenosis, using a M Mode Echocardiographic study. In 19% of the group the left ventricular function was abnormal, however, we were able to distinguish three subsets: small left ventricular dimension, normaland dilated. In the first two subsets, the cardiac performance was normal in almost all the patients (85%). In 15%, the left ventricular function was depressed, probably due to a restricting flow into the cavity, segmental atrophy and fibrosis caused by chronic mitral obstruction. In the last group (dilated left ventricle), the end-systolic dimension was abnormal in 71,4% of the patients. Our study suggests that the increased dimension of the left ventricle is accompanied by poor ventricular performance and represents an intrinsic trace of damage of the myocardium by the previous rheumatic carditis. The importance of detecting this last subset is emphasized due to the high incidence of impairment in left ventricular function. This detection could in some cases prevent the surgical treatment when this function is severely depressed.