Midterm Outcomes of Isolated Coronary Artery Bypass Grafting in the Setting of Moderate Ischemic Mitral Regurgitation.

INTRODUCTION: Although randomized trial data exist for 2-y outcomes comparing isolated coronary artery bypass grafting (CABG) versus CABG with concomitant mitral valve repair (CABG + MVr) for the treatment of moderate ischemic mitral regurgitation (IMR), longer term outcomes are unclear. This study evaluated the longitudinal outcomes of isolated CABG for moderate IMR. METHODS: Patients with moderate IMR undergoing isolated CABG from January 2010 to February 2018 at a single institution were included. Outcomes included longitudinal freedom from heart failure readmission, survival, rates of persistent mitral regurgitation (MR), and freedom from mitral valve reinterventions. A subanalysis was conducted comparing CABG versus CABG + MVr. Multivariable Cox regression was used for risk adjustment. RESULTS: A total of 528 patients with moderate IMR underwent isolated CABG. Postoperatively, 26% of patients had at least moderate MR at 1-mo follow-up, although at 5 y progression to severe MR was rare (2.2%) as were mitral valve reinterventions (0.2%). Survival at 30 d (95.8%), 1 y (89.6%), and 5 y (76.6%) was acceptable. Furthermore, the freedom from readmission for heart failure was also acceptable at 30 d (92.6%), 1 y (79.9%), and 5 y (65.0%) postoperatively. In a subanalysis comparing CABG versus CABG + MVr, unadjusted and risk-adjusted survival, freedom from heart failure readmissions, mitral valve reinterventions, and degrees of MR were comparable between the groups at all intervals (all P > 0.05). CONCLUSIONS: The majority of patients with moderate IMR can undergo isolated CABG with acceptable rates of heart failure readmissions, survival, progression to severe MR, and the need for subsequent mitral interventions. These data support the use of isolated CABG in patients with moderate IMR.