[Change in mitral valve area after percutaneous transvenous mitral commissurotomy: prediction of mitral valve restenosis].

Factors indicating changes in mitral valve area after single-balloon percutaneous transvenous mitral commissurotomy (PTMC) were evaluated in 53 patients receiving PTMC by follow up for 3-48 months (mean 18 +/- 12 months) using serial transthoracic echocardiography to measure mitral valve area by planimetry. The echocardiographic scores of the mitral commissures and mitral valve, and other clinical variables were assessed. Mitral valve area showed an immediate increase from 1.1 +/- 0.3 to 1.8 +/- 0.3 cm2 (p < 0.01). There was a small but significant decrease in mitral valve area at follow-up to 1.6 +/- 0.4 cm2 (p < 0.01). Restenosis (a decrease in mitral valve area of more than 25% from immediately after PTMC to follow-up) occurred in nine patients (17%). There was no significant correlation between clinical or echocardiographic features and an increase in mitral valve area immediately after PTMC. The total echocardiographic score of the mitral commissures correlated with the decrease in mitral valve area at follow-up (r = 0.42, p = 0.002). Multiple regression analysis showed the total echocardiographic score of the mitral commissures was the best indicator of a decrease in mitral valve area at follow-up (p = 0.0059). Six of nine patients with restenosis had a commissure score of more than 3, while only five of 44 patients without restenosis had a commissure score of more than 3 (p < 0.01). Mitral valve area increases significantly immediately after PTMC, and decreases significantly at follow-up.(ABSTRACT TRUNCATED AT 250 WORDS)