Urgent/emergent surgical revascularization in unstable angina: influence of different type of conduits.

AIM: In patients with unstable angina (UA) undergoing nonelective myocardial revascularization we compare the outcomes of skeletonized bilateral internal mammary arteries (BIMA) vs left internal mammary artery (LIMA) and saphenous vein grafts (SVGs) vs SVGs only.

METHODS

Between January 1997 and December 2003, 758 patients: 612 (80.7%) males, mean age 62+/-12 years, underwent nonelective coronary artery bypass grafting (CABG) for unstable angina; 205 (27%) were operated emergently and 553 (73%) urgently. BIMA were employed in 320 (42%) patients (Group B) , isolated LIMA and/or SVGs in 332 (44%) patients (Group M) and only SVGs in 106 (14%) (Group S).

RESULTS

In-hospital mortality (B=5.9%, M=4.5% and S=7.5%), and perioperative myocardial infarction (B=2.2%; M=1.9%, S=3.7%) were similar between the 3 groups (P=NS). Actuarial survival at 1, 3 and 7 years was 98.7%, 97.5% and 96.2% in group B, 99.3%, 94.8% and 89.4% in group M (P< 0.057 at 7 years follow-up) and 98%, 93.2% and 84.3% in group S (P=0.001). At 7 years follow-up, the event-free cardiac survival (92% vs 89.1%, P=0.045), angina-free survival (98.6% vs 95.8%, P=0.056), reoperation-free cardiac survival (98% vs 96%, P= 0.05) and infarct-free cardiac survival (98.7% vs 96.9%, P=0.062) showed a consistent trend to be superior in group B. Multivariate analysis identified age >65 years (P= 0.02), left ventricular ejection fraction (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 nonelective CABG for UA is safe and effective. There is a trend, however, toward a survival benefit with improved freedom from late cardiac events (recurrence of angina, freedom from reoperation and infarction).