Role of an operative score in mitral reconstruction in dominantly stenotic lesions

OBJECTIVE: The role of an operative score in selection and results of mitral valve reconstruction in dominantly stenotic mitral lesions was assessed. METHODS: A total of 136 patients consecutively underwent reconstruction for rheumatic mitral stenosis with or without regurgitation from December 1989 through December 1994. Mitral valve structure was scored for cuspal pliability and thickness, cuspal area loss, chordal length, papillary muscle length, annular dilatation and degree of associated regurgitation and calcification. A score of 0 indicated normal valve while a score of 24 indicated a grossly deformed valve. Age, sex, functional class, cardiac rhythm, mitral valve orifice area, left ventricular and left atrial dimensions, transmitral gradients, pulmonary artery pressures and thoroughness of repair were evaluated. RESULTS: Mitral valve architecture was disorganised moderately in 50 (37%) and severely in 69 (52%) patients. Extent of thoroughness in different operative techniques correlated with good (n = 30) or adequate (n = 60) outcome. Mean mitral valve orifice area increased from 0.77 +/- 0.2 to 2.56 +/- 0.6 cm2, peak gradient dropped from 20.3 +/- 6.2 to 8.6 +/- 3.5 torr, mean gradient from 13.5 +/- 4.9 to 4.76 +/- 2.2 torr and end-diastolic gradient from 10.1 +/- 5.0 to 3.2 +/- 1.9 torr. Lack of recognition of anatomical details and of all necessary componental measures constituted the learning curve of different operators. CONCLUSIONS: Recurrent disease, learning curve, inadequate repair and higher operative mitral valve score were the factors for poorer results in the intermediate term follow-up to 64 months. Thoroughness of repair was the most important correlate of outcome and indicative of expertise.