Abstract 19433: Should Bilateral Internal Thoracic Artery Grafting be Used in Patients After Recent MI?

Abstract

Introduction: Bilateral internal thoracic artery(ITA) grafting is associated with improved survival. However, many surgeons are reluctant to use this revascularization technique in patients after myocardial infarction (MI) due to the risk of sternal infection and the excellent survival benefit obtained with single ITA (SITA). Hypothesis: Long-term outcome of bilateral ITA (BITA) grafting, might be superior to single ITA and other conduits such as saphenous veins (SVG) and radial artery (RA) in patients with multi-vessels disease after recent MI. Methods: 871 patients who underwent BITA grafting after recent MI (<3 months prior to surgery), between 1996 and 2010, Were compared with 527 who underwent CABG with SITA and SVG or RA. Results: Patients undergoing SITA were older, more often female, more likely to have COPD, EF<30%, preoperative critical state, Diabetes, chronic renal failure (CRF), peripheral vascular disease (PVD) and emergency operation. In contrast, patients undergoing BITA grafting were more likely to have triple vessel disease and more often underwent CABG with three or more grafts and sequential grafts. Operative mortality of BITA patients was lower (3.0 % vs. 5.7%, in the SITA group p=0.01), Occurrences of sternal wound infection (3% vs 2%) and strokes (2.6% vs. 3%) were similar. Mean follow-up was 11.8 (95%CI 10.95-12.56) years. Kaplan Meier survival of BITA patients was better (70.3% vs.52.6% p<0.001). Propensity score matching was used to account for differences between groups in preoperative characteristics. The 293 matched pairs thus created had similar preoperative characteristics. Kaplan Meier 10 year survival (67.3% versus 59%, p=0.325 log-rank test), and the Cox adjusted survival of the matched groups did not reach statistical significance (HR 1.57, p=0.091). However, survival of non- emergent BITA patients was better (HR 1.256 p=0.038). Age, COPD, CHF, CRF, PVD and left main were independent predictors of decreased survival. Off-pump operations were associated with improved survival (Cox model) Conclusions: This study suggests that long-term outcome of arterial revascularization with BITA can be better than that of SITA in non-emergency cases after recent MI with proper patient selection