Open mitral commissurotomy: The 'golden standard'

Background and aim of the study: Percutaneous balloon mitral commissurotomy (PBMC) has recently emerged as an alternative to surgical commissurotomy f or the treatment of rheumatic mitral valve stenosis. However, this blind pr ocedure may result in incomplete separation of the commissures, which could lead to accelerated restenosis. Hence, open mitral commissurotomy (OMC), w hich is a visually oriented procedure, remains our method of choice. This s tudy was aimed at assessing the long-term outcome of the OMC procedure. Methods: A series of OMC performed between 1988 and 1991, involving 100 mit ral valves, each with a preoperative echocardiographic score less than or e qual to 10 was investigated clinically and by echocardiography. Results: Postoperatively, the mean valve area achieved was 2.89 +/- 0.49cm( 2), compared with a mean preoperative value of 0.99 + 0.23cm(2). In a recen t follow up, conducted after a mean of 8.5 years (range: 7-11 years), the m ean valve area measured by echo-Doppler in this patient group was 2.37 +/- 0.42cm(2) (range: 1.6 - 3.6 cm(2)), and 81% of patients had a valve area >2 .0 cm(2). Reoperation was required in only two cases. The late mortality ra te was 4% (0.5%/pt-yr), and was in no case valve-related. Two-thirds of the patients had no or only mild mitral insufficiency, and 93% were in NYHA fu nctional class I or II. The nine-year actuarial survival rate was 96%, free dom from reoperation 98%, and freedom from all valve-related complications 92%. Complementary to this experience, during the past 10 years we have per formed modified OMC in 919 (79%) of all 1,151 patients with mitral stenosis submitted for surgery, including 257 with mixed disease. The mean post-com missurotomy valve area (2.9 cm(2)) was identical to that of the study group . Moderate to severe valve calcification was not an absolute contraindicati on to valve conservation. Conclusion: OMC remains the best alternative for the treatment of all cases of mitral stenosis, independently of the degree of pliability. In our expe rience, the medium- and long-term results are significantly better than tho se usually reported in PBMC series.