Follow-up of patients undergoing percutaneous mitral balloon valvotomy. Analysis of factors determining restenosis

Abstract

This study reports the clinical follow-up (13 ± 1 months) of 100 consecutive patients who underwent percutaneous mitral valvotomy (PMV). Echocardiographic (n =32) and cardiac catheterization (n = 37) data from this group are also included. Patients were divided into two groups by an echocardiographic score. PMV resulted in a good hemodynamic result (post-PMV mitral valve area, ≥ 1.5 cm2) in 88% of patients with a score of 8 or less and 44% of patients with a score of more than 8. Eighty-eight percent of patients with a score of 8 or less (n =57) were New York Heart Association (NYHA) functional Classes III and IV before PMV; at follow-up, 81% were NYHA Class I and 12% were NYHA Class II. There were no deaths; three patients underwent mitral valve replacement (MVR). Ninety-eight percent of patients with a score of more than 8 (n = 43) were NYHA Classes III and IV before PMV; at follow-up, 58% were NYHA Classes I and II. Seven patients who did not improve and were not surgical candidates died 3.8 ± 1.2 months after PMV. Nine patients who were surgical candidates underwent elective MVR at 4 ± 0.9 months after PMV. Repeat cardiac catheterization demonstrated restenosis in only one of 27 patients (4%) with a score of 8 or less. Mitral valve area after PMV was 1.9 ± 0.1 cm2 and at follow-up was 2 ± 0.1 cm2 (NS). In contrast, in patients with a score of more than 8 (n = 10), mitral valve area decreased from 1.8 ± 0.1 cm2 (after PMV) to 1.1 ± 0.1 cm2 at follow-up (p < 0.01). Restenosis was demonstrated in seven of 10 patients (70%) with a score of more than 8. Multivariate analysis showed echocardiographic score and the presence of atrial fibrillation as predictors of restenosis. At ventriculography, the severity of mitral regurgitation after PMV decreased by one grade in 53% of patients. Thus, PMV produces excellent immediate and follow-up results in patients with a score of 8 or less; suboptimal results immediately after PMV, and hemodynamic restenosis are more likely to occur in patients with a score of more than 8.