In 53 patients with rheumatic mitral stenosis we performed echocardiographic study in order to define anatomic and functional alterations. We used 3.5 MHZ probe and obtained images from apical and parasternal windows. Determinations were performed by standards of the American Society of Echocardiography. Thirteen patients were men and forty women. Men's mean age was 43.5 years and women's mean age 40 years. In the men anatomic mitral valve area was 1.1 cm2 and in the women 1.3 cm2. Correlation anatomic to functional valve area was strong (r = 0.9). Mitral diastolic gradient had correlation with cardiac output, mitral valve area and ejection fraction. Pulmonary artery pressure had strong correlation with valve area and cardiac output. In conclusion, our study showed the usefulness of functional valve area in the graduation of mitral stenosis, the dependence of the mitral diastolic gradient of several cardiac events, the independence of the left atrium dimensions and also the strong dependence of pulmonary artery pressure of cardiac output and valve area.