Overall patients with rheumatic valvular heart disease were examined. Commissural mitral stenosis (CMS) was revealed in 70 patients (35 %). At the preliminary examination stage CMS was not detected in 57 % of patients, the tone of mitral valve opening could not be heard in 40 %, normal configuration of the heart was preserved in 20 % of patients according to the roentgenography data. The echocardiographic features of CMS were revealed: the lack of a cupola-shaped diastolic curvature of the mitral cusp in part of patients, an insignificant narrowing of the left venous opening.