Skeletonized bilateral internal mammary arteries for non-elective surgical revascularization in unstable angina.

OBJECTIVE: The aim of this study was to evaluate the feasibility, safety and outcome of skeletonized bilateral internal mammary arteries (BIMA) in patients with unstable angina (UA) undergoing non-elective myocardial revascularization. METHODS: Between January 1997 and December 2003, 758 patients, mean age 62+/-12 years, underwent non-elective coronary artery bypass grafting (CABG) for unstable angina. Two hundred and five (27%) were operated emergently and 503 (73%) urgently. BIMA were employed in 320 (42%) patients (Group B) and isolated left IMA and/or saphenous vein grafts in the remaining 438 (58%) patients (Group M). RESULTS: In-hospital mortality (B = 5.9% and M = 5.3%), and perioperative myocardial infarction (B = 2.2%; M = 1.96%) were similar between the two groups (P = ns). Actuarial survival at 1, 3 and 7 years was 98.7, 97.5 and 96.2% in B and 99, 94.3 and 88.4% in M (P < 0.05 at 7 years follow-up). At 7 years follow-up, the event-free cardiac survival (92 vs. 87%, P = 0.021), angina-free survival (98.6 vs. 94%, P = 0.039), reoperation-free cardiac survival (98 vs. 95%, P = 0.04) and infarct-free cardiac survival (98.7 vs. 96%, P = 0.05) were better in Group B. Multivariate analysis identified age > 65 years (P = 0.02), LVEF < 35% (P = 0.01), > 1 ischemic irreversible area (P = 0.03) as independent predictors for late deaths, while the use of the LIMA (P=0.006) and both mammary arteries (P=0.001) decreased the risk of late deaths. CONCLUSIONS: The use of BIMA in non-elective CABG for UA is safe and effective. Mid-term outcome, however, are superior with improved freedom from cardiac death, from coronary reintervention and from myocardial infarction.