[Third mitral valve replacement--review of clinical aspects and surgical management in 10 cases].

Third mitral valve replacement (3rd MVR) have become more frequent as use of replacement procedures has become more widespread. However, little information exists to clearly document the determinants of 3rd MVR. To evaluate backgrounds and risks and complications of 3rd MVR, we reviewed data on 10 patients (6 male and 4 female, age averaged 58 +/- 8 years) who underwent 3rd MVR because of prosthetic valve malfunction during December 1986-May 1995. This represented 7.1% of total number of reoperations for valve surgery (10/140) during that period. The incremental effect of the 3rd MVR on hospital mortality and mobidity was studied by comparing first mitral valve replacement (1st MVR) and second mitral valve replacement (2nd MVR) and 3rd MVR. After an interval of 134 +/- 23 months, 3rd MVR was undertaken for congestive heart failure due to primary tissue failure in 65%, paravalvular leakage in 20%, prosthetic valve endocarditis in 15%. One patient died at 11 days postoperatively, for a mortality rate of 10%. Cause of death was related to multiple organ failure due to low cardiac output syndrome. The surgical risk of 2nd MVR and 3rd MVR is higher than that of 1st MVR, but there is no conclusive evidence that the difference between 2nd MVR and 3rd MVR is statistically significant. With improvement intraoperative strategies, the operative risk in patients undergoing 3rd MVR has been markedly reduced.