Late evolution of mitral commissurotomy in patients with low echocardiographic score

Objective: The purpose of this study was to analyze the late results with open mitral commissurotomy in patients with low echocardiographic scores and to identify variables influencing these late results. Methods: We studied 50 patients who underwent open mitral commissurotomy due to rheumatic mitral stenosis at the Heart Institute University of Sao Paulo Medical School. Enrolled patients had a Wilkins echocardiographic score less than or equal to 9 and a mean mitral valve area (MVA) of 0.94 +/- 0.19 cm(2). Patients underwent clinical, electrocardiographic, and echocardiographic evaluations preoperatively, immediate postoperatively, at 6 months, at 12 months, and then annually for 11 years. Results: There was no hospital mortality. During 383.58 patient/years of follow-up, there were two late deaths, one related to valve disease. Actuarial survival was 94.3 +/- 4.0% at 11 years. The linearized reoperation rate was 1.3% patient/year, and the linearized thromboembolism rate was 0.8% patient/year. No patients developed endocarditis. The mean MVA was 2.50 +/- 0.44 cm(2) during the immediate postoperative period, decreasing to 1.74 +/- 0.4 cm(2) over 60 months (P < 0.01). Although it was 1.40 +/- 0.24 cm(2) at 132 months, variations observed after 60 months were not significant. In regard to MVA, patients with higher echocardiographic scores had worse late results than patients with low scores (P = 0.002). Neither the grade of subvalvular apparatus involvement nor MvAs during the preoperative and immediate postoperative periods significantly influenced the late evolution of MVAs. Conclusions: Open mitral commissurotomy produces satisfactory results in patients with low echocardiographic scores. (C) 2004 Elsevier B.V. All rights reserved.