Mitral regurgitation surgery in patients with ischemic cardiomyopathy and ischemic mitral regurgitation: factors that influence survival

Abstract

Objective: The treatment of patients with ischemic cardiomyopathy and concomitant mitral regurgitation can be challenging and is associated with reduced long-term survival. It is unclear how mitral valve repair versus replacement affects subsequent outcome. Therefore, we conducted this study to understand the predictors of mortality and to delineate the role of mitral valve repair versus replacement in this high-risk population.

Methods: From 1993 to 2007, 431 patients (mean age, 70 ± 9 years) with ischemic cardiomyopathy (left ventricular ejection fraction ≤ 45%) and significant ischemic mitral regurgitation (>2) were identified. Patients (44) with concomitant mitral stenosis were excluded from the analysis. A homogeneous group of 387 patients underwent combined coronary artery bypass grafting and mitral valve surgery, mitral valve repair in 302 (78%) and mitral valve replacement in 85 (22%). Uni- and multivariate analyses were performed on the entire cohort, and the predictors of mortality were identified in 2 distinct risk phases. Furthermore, we specifically examined the impact of mitral valve repair versus replacement by comparing 2 propensity-matched subgroups.

Results: Follow-up was 100% complete (median, 3.6 years; range, 0-15 years). Overall 1-, 5-, and 10-year survivals were 82.7%, 55.2%, and 24.3%, respectively, for the entire group. The risk factors for an increased mortality within the first year of surgery included previous coronary artery bypass grafting (hazard ratio = 3.39; P < .001), emergency/urgent status (hazard ratio = 2.08; P = .007), age (hazard ratio = 1.5; P = .03), and low left ventricular ejection fraction (hazard ratio = 1.31; P = .026). Thereafter, only age (hazard ratio = 1.58; P < .001), diabetes (hazard ratio = 2.5; P = .001), and preoperative renal insufficiency (hazard ratio = 1.72; P = .025) were predictive. The status of mitral valve repair versus replacement did not influence survival, and this was confirmed by comparable survival in propensity-matched analyses.

Conclusions: Survival after combined coronary artery bypass grafting and mitral valve surgery in patients with ischemic cardiomyopathy (left ventricular ejection fraction ≤ 45%) and mitral regurgitation is compromised and mostly influenced by factors related to the patient's condition at the time of surgery. The specifics of mitral valve repair versus replacement did not seem to affect survival.