Percutaneous mitral balloon valvuloplasty (PMBV) is an accepted alternative treatment to open and closed mitral commissurotomy or mitral valvular replacement. The Inoue technique has become standard in most centers. In our first 24 percutaneous balloon mitral valvuloplasties by the Inoue technique, 23 procedures were technically successful. The mean age of the patients was 53 (24-75) years. There were 22 women. Four patients had a history of closed mitral commissurotomy, one of previous mitral balloon valvuloplasty, and one of aortic metallic valve replacement. The mean echocardiographic mitral Wilkins score was 7.3 (range 4-13). PMBV resulted in significant improvement of hemodynamic values. The mean mitral pressure gradient fell from 12 +/- 5 to 5 +/- 3 mm Hg (p = 0.0001) and the cardiac index increased from 2.7 +/- 0.7 to 3.0 +/- 0.8 l/min/m2. The valve area by the Gorlin formula increased from 1.2 +/- 0.3 to 2.1 +/- 0.6 cm2 (p = 0.0001). Doppler and planimetric echocardiography data were in keeping with hemodynamic data. Mitral valve regurgitation increased by more than 1 grade in 3 patients, 2 of whom subsequently underwent valve replacement. No tamponade occurred with the Inoue technique. There was 1 fatal outcome following tamponade and emergency heart surgery after mitral valvuloplasty with a Trefoil balloon employed in a subsequent intervention due to impossibility of placing the Inoue balloon. Left-to-right shunting at the atrial level after the intervention was not significant in any patient. 21 patients (88%) had improvement in their functional class. One of the patients with unchanged functional class had late onset of severe mitral regurgitation, another had a technical failure with the Inoue technique, and in 1 patient with calcified valve leaflets significant mitral stenosis persisted. At 3 to 15 months follow-up echocardiography was performed in 19 patients: mitral valve areas had not changed significantly compared to post-interventional values. One patient had a new mitral regurgitation compared with the situation immediately after PMBV. Mitral balloon valvuloplasty by the Inoue technique is an effective treatment with low risk in patients with symptomatic mitral stenosis.