Late outcome of mitral valve surgery for patients with coronary artery disease.

Background: We plan to determine whether the cause of mitral valve regurgitation, ischemic or degenerative, affects survival after combined mitral valve repair or replacement and coronary artery bypass grafting (CABG) surgery and to assess the influence of residual mitral regurgitation on late outcome.
Methods: A retrospective study was made of 302 patients having mitral valve repair or replacement and CABG from January 1987 through December 1996. Risk factors for death, for development of New York Heart Association class III or IV congestive heart failure (CHF), and recurrent mitral valve regurgitation were identified by proportional hazards analysis.
Results: The cause of mitral regurgitation was ischemic in 137 patients (45%) and degenerative in 165 patients (55%). Valve replacement was performed in 51 patients (17%) and valve repair in 251 patients (83%). Median follow-up was 64 months. Ten-year actuarial survival rates were 33% (95% confidence interval: 22% to 47%) in the ischemic group and 52% (95% confidence interval: 42% to 64%) in the degenerative group. Univariate predictors of death, were entered into a multivariate model. Older age, ejection fraction of 35% or less, three-vessel coronary artery disease, replacement of the mitral valve, and residual mitral regurgitation at dismissal were independent risk factors for death. The cause of mitral valve regurgitation (ischemic or degenerative) was not an independent predictor of long-term survival, class III or IV CHF, or recurrent regurgitation.
Conclusions: Survival after mitral valve surgery and CABG is determined by the extent of coronary disease and ventricular dysfunction and by the success of the valve procedure; etiology of mitral valve regurgitation has relatively little impact on late outcome.