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 for the treatment of rheumatic mitral valve stenosis. However, this blind procedure may result in incomplete separation of the commissures, which could lead to accelerated restenosis. Hence, open mitral commissurotomy (OMC), which is a visually oriented procedure, remains our method of choice. This study was aimed at assessing the long-term outcome of the OMC procedure.

METHODS

A series of OMC performed between 1988 and 1991, involving 100 mitral valves, each with a preoperative echocardiographic score < or =10 was investigated clinically and by echocardiography.

RESULTS

Postoperatively, the mean valve area achieved was 2.89+/-0.49 cm2, compared with a mean preoperative value of 0.99+/-0.23 cm2. In a recent follow up, conducted after a mean of 8.5 years (range: 7-11 years), the mean valve area measured by echo-Doppler in this patient group was 2.37+/-0.42 cm2 (range: 1.6 - 3.6 cm2), and 81% of patients had a valve area >2.0 cm2. Reoperation was required in only two cases. The late mortality rate 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 functional class I or II. The nine-year actuarial survival rate was 96%, freedom from reoperation 98%, and freedom from all valve-related complications 92%. Complementary to this experience, during the past 10 years we have performed modified OMC in 919 (79%) of all 1,151 patients with mitral stenosis submitted for surgery, including 257 with mixed disease. The mean post-commissurotomy valve area (2.9 cm2) was identical to that of the study group. Moderate to severe valve calcification was not an absolute contraindication 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 experience, the medium- and long-term results are significantly better than those usually reported in PBMC series.