Echocardiography was performed to compare pre- and postoperative findings and to evaluate the postoperative state in 109 patients with mitral stenosis (MS) including 22 who underwent closed mitral commissurotomy (CMC) (34.3 +/- 6.9 y.o.); 71, open mitral commissurotomy (OMC) (42.9 +/- 8.7 y.o.); and 16, mitral valve replacement (MVR) (44.5 +/- 8.9 y.o.). Echocardiographic examinations were performed using a Toshiba SSL-51H with a mechanical sector scanner or an SSH-11A with a phased-array electronic sector scanner, one or two weeks before and about one month after surgery, and were reviewed yearly. The results were as follows: The E-F slope of the anterior mitral leaflet (AML) and mitral valve orifice area (MVA) were significantly increased after cardiac surgery in both the CMC and OMC groups. The amplitude of the mitral valve was slightly increased in the CMC group, but was unchanged in the OMC group. Before surgery, the left atrial dimension (LAD) was larger in the MVR group than in the other two groups, and it was significantly decreased after surgical intervention in all three groups. The aortic dimension (AOD) was slightly increased in the majority of patients, and the ratio of the aortic dimension to the sum of the aortic and left atrial dimensions [AOD/(AOD + LAD)] was significantly increased after cardiac surgery due to the improvement of cardiac function and the resolution of the left atrial enlargement. Repeated echocardiography facilitated follow-up of the state of the mitral valve and of cardiac performance, and is considered useful in determining indication for reoperation.