Percuaneous mitral valvuloplasty(PMV) is an alternative to surgical mitral commissurotomy for patients with mitral stenosis. To assess the immediate and follow-up results of PMV and to identify factors in fluencing the outcome and coplications of PMV, we analyzed the clinical, echocardiographic and hemodynamic data of 108 patients who underwent PMV. 1) Good hemodynamic results were obtained in 86 patients(79.6%). The factors predicting immediate outcome of PMV were mitral valve mobility, total echoscore, and EBDA/BSA. 2) Predictors of the increase in mitral valve area by PMV were age, sex, rhythm, and NYHA functional class before PMV. The independant predictors were rhythm(p=0.008) and functional class(p=0.002). 3) The degree of mitral regurgitation increased in 26 patients(24%), did not changed in 79 patients(73%) and decreased in 3 patients(3%). The increase of MR could not predicted from any features of the clinical, echocardiographic or hemodynamic daa. The severity of MR decreased by one grade in 15% of patients and did not change in 66% of patients during follow-up. 4) Left-to-right shunt was detected in 19 patients(18%). The predictors were valve mobility, pulmonary artery pressure and pulmonary vascular resistance. 5) Follow-up catheterization(mean 14 months) identified restenosis in six of 16 patients. The predictors of restenosis were sex, total echosecore, and left atrial volume. 6) The hemodynamic data at follow-up were good compared with prePMV data(p<0.01), but follow-up miral valve area decreased than that of postPMV(p<0.05). Immediate decrease in pulmonary vascular resistance followed by progressive improvement during follow-up. 7) Immediate complications of PMV were peripheral arterial embolism in one patient(1%), pericardial effusion in two(2%), transient arrhythmia in four(4%), left-to-right shunt in nineteen(18%) and increase in the grade of MR in twenty-six(24%). This study suggests, that PMV produces excellent immediate and follow-up results and is a safe and effective procedure in the nonsurgical treatment of mitral stenosis.