Long-term influence of mild or moderate ischemic mitral regurgitation after off-pump coronary artery bypass surgery

BACKGROUND: The issue of mild to moderate ischemic mitral regurgitation (IMR) is controversial alter conventional surgery, and has not been specifically studied after off-pump coronary artery bypass graft (OPCAB) surgery. OBJECTIVE: To review the influence of mild or moderate IMR on long-term survival and recurrent cardiac events after OPCAB surgery. METHODS: A total of 1000 consecutive and systematic OPCAB patients who underwent operations between September 1996 and March 2004 were prospectively followed. Sixty-seven patients (6.7%) had odd to moderate IMR at the time of surgery. Operative mortality, actuarial survival and major adverse cardiac event-free survival were studied to assess the effect of IMR. RESULTS: The mean (+/- SD) follow-up period was 66 22 months and was completed in 97% of the cohort. IMR patients were older (P<0.001), and had lower ejection fractions (P<0.001) and more comorbidities. More female patients presented with IMR (P=0.002). Operative mortality (P=0.25);old prevalence of perioperative myocardial infarct ion (P=0.25) were comparable for both groups. Eight-year survival was decreased in IMR patients (P<0.001), but;titer adjusting for risk factors in the Cox regression model, mild to moderate IMR was not found to be a significant risk factor of long-term mortality (P=0.42). Major adverse cardiac event-tree survival at eight years was significantly lower in IMR patients (P<0.001) and, more specifically, in patients with 2+ IMR. After adjusting for risk factors, IMR remained a significant cause of poor outcome (hazard rat us 2.09), especially for recurrent congestive heart failure and myocardial infarction. CONCLUSIONS: OPCAB patients with preoperative mild or moderate IMR had a higher prevalence of preoperative risk factors than those without IMR. They had comparable perioperative mortality;sod morbidity but, over the long term, were found to be at risk for recurrent cardiac events.