Redo mitral valve surgery-a long-term experience

BACKGROUND: Our experience with reoperative mitral valve (MV) surgery over a 27-year period is presented here. METHODS: From January 1975 to June 2002, 11,908 operations were performed for MV disease. Out of these 744 were reoperations. The mean age at primary operation was 23.6 +/- 10.1 years (range 2 to 53 years) and at reoperation was 36.0 +/- 11.0 years (range 6 to 65 years) with a mean interval of 11.5 +/- 2.5 years. Mitral valve replacement (MVR) was performed following previous closed mitral valvotomy (CMV) in 408 patients, open mitral commissurotomy (OMC) in 21 patients, and MV repair in 58 patients, MVR in 80 patients, homograft mitral valve replacement (HMVR) in 11 patients. The reasons for reoperation were mainly progression of lesions. Valve thrombosis and endocarditis were indications for reoperation following MVR. Twenty-eight patients underwent redo CMV, 53 patients underwent OMC, and 14 patients underwent MV Repair. RESULTS: Early mortality was 5.64% (n = 42). Hemorrhage and low cardiac output were the major causes. Follow-up was 124.8 +/- 30.5 months (2 to 300 months). Follow-up was 88%. There were no late deaths in the valve repair group. There were three episodes of thromboembolism in this group (0.3% per patient-year). In the valve replacement group there were six late deaths; three due to valve thrombosis, one due to infective endocarditis, and two due to anticoagulant-related hemorrhage. There were 13 episodes of thromboembolism in this group (0.6% per patient-year). CONCLUSION: Redo MV surgery is safe and can be undertaken with acceptable mortality and morbidity.