Mitral valve area after PMV increased in all patients, from 0.9±0.2 to 1.8±0.4cm²(P<0.0001). In valve area estimation, the correlation between Gorlin`s method and 2-Dechocardiography was better(r=0.61, p<0.0001) than that between Gorlin`s method and Doppler pressure halftime(r=0.38, P<0.01) before valvuloplasty, but after the procedure Gorlin`s and 2-D image valve area correlated less well(r=0.33, P<0.05) than Gorlin`s-Doppler pressure halftime correlation(r=0.46, P<0.002).

Before PMV, 37 patients had no mitral regurgutation, 7 had grade 1 and 1 had grade 2 mitral regurgutation. After PMV, new mitral regurgutation occurred in 14 patients, increased in severity in 5 patients and so mitral regurgutation newly developed or increased in severity in 19(42%) patients.

There were no differences between the patients with and those without an increase in mitral regurgutation after PMV, in age, sex, caediac rhythm, initial mitral valve area, increase in mitral valve area and fluoroscopic calcification. However, morphologic characteristics especially mobility(P<0.01) and thickening(P<0.05) of mitral leaflets were better pressured, and EBDA/BSA(effective balloon dilating area/body surface area) was significantly smaller(P<0.02) in patients without an increase in mitral regurgutation.

Thus, an increase in mitral regurgutation after PMV might be related to the features of valve morphology especially and thickand EBDA/BSA.