Surgery for ischemic mitral regurgitation: should the valve be repaired?

Background And Aim Of The Study: Patients with ischemic cardiomyopathy undergoing coronary artery bypass grafting (CABG) often have concomitant mitral regurgitation (MR). Repairing the valve at the time of surgery is not universally accepted. The results of CABG with or without mitral valve annuloplasty (MVA) were compared in patients with reduced left ventricular (LV) function and ischemic MR.

Methods: Among a total of 195 patients, 108 underwent isolated CABG, and 87 underwent CABG with MVA. The study end-points included survival, degree of MR, and NYHA functional class.

Results: Patients in the MVA group were younger (mean age 63 +/- 10 versus 68 +/- 9 years; p <0.001), but had a more severe cardiac pathology, with severe LV dysfunction in 45% versus 26% (p = 0.006) and severe MR in 82% versus 14% (p < 0.001). The operative mortality was 9%, and similar in both groups. The follow up was complete, with a mean survival period of 87 +/- 50 months. Although, overall, no improvement was seen in LV function, symptomatic improvement was more pronounced in the MVA group (p = 0.006). At follow up, residual MR was present in 2% of the MVA group and in 47% of the CABG-only group (p < 0.0001). For the MVA and CABG-only groups, respectively, survival at five and 10 years was 68% and 46% versus 77% and 52% (p = NS). By multivariate analysis, neither degree of MR nor LV function at follow up had any impact on survival.

Conclusion: In patients with a reduced LV function undergoing CABG, the addition of a mitral annuloplasty does not increase the operative risk. Although patients in the MVA group were more ill, there was a better symptomatic improvement in this group, and they attained a similar survival. It is recommended that MVA be performed at the time of CABG in patients having moderate or greater MR associated with a reduced LV function.