Since May 1991 to July 1993, 121 patients (mean age 50 +/- 13 years, 23 males and 98 females) underwent 122 percutaneous mitral valvuloplasty according to Inoue's technique. Following Wilkins criteria the indications for the procedure were given on the basis of the echo-score (ideal cases with score < or = 8). Echo-score was > 8 in 59 patients (49%), and < or = 8 in 62 (51%); 19 patients (16%) had previous surgical mitral commissurotomy and 36 (30%) had previous embolic events. All patients were successfully treated except for 5 who developed mitral regurgitation 3+/4+. In 1 patient the procedure was unsuccessfully performed for the low increase in mitral valve area. All these patients except 1 were referred to elective surgery. Mitral valve area increased from 1.1 +/- 0.2 to 2.1 +/- 0.4 cm2 (p < 0.001) and transvalvular gradient fell from 15 +/- 6 to 6 +/- 3 mmHg (p < 0.001). Patients with previous surgical commissurotomy had a lower increase in the mitral valve area than patients without previous surgery (p < 0.006). Patients with echo-score > 8 presented a lower, but not significant, increase in mitral valve area after valvuloplasty; patients with mono-commissural calcifications had worse results than those without calcifications (p < 0.03). At 12 and 24 month follow-up 9 and 3 restenosis respectively occurred, but in 10 of these cases the residual valvular area was > 1.5 cm2. The Authors conclude that in patients with good anatomy percutaneous mitral valvuloplasty is an effective and safe treatment.(ABSTRACT TRUNCATED AT 250 WORDS)