First time myocardial revascularization in patients younger than 70 years. Single versus double internal mammary artery

Abstract

Background: We evaluated the early and late outcomes of bilateral internal mammary artery (BIMA) grafting, with or without saphenous vein grafts (SVGs), compared to single internal mammary artery and SVGs in patients < 70 years undergoing first myocardial revascularization.

Methods: From September 1986 to December 1999, 1389 patients underwent first myocardial revascularization using the left internal mammary artery (LIMA) to the left anterior descending artery and SVGs (n = 480) or BIMA (one internal mammary artery on the left anterior descending artery) with or without SVGs (n = 909). Propensity score analysis was used to select 952 (476 of each group) patients with the same preoperative and operative characteristics. Thirty-day outcome and 10-year freedom from all-cause death, cardiac death, acute myocardial infarction (AMI), AMI in a grafted area, redo/percutaneous transluminal coronary angioplasty (PTCA), redo/PTCA in a grafted artery, cardiac events and any events, were evaluated. Follow-up ranged from 3.5 to 16.8 years (mean 8.8+/-4.0 years).

Results: Thirty-day mortality was 2.9% in the LIMA group and 1.9% in the BIMA group, p = NS; the BIMA group showed a better 10-year freedom from all-cause death (92.4+/-2.1 vs 87.5+/-3.5%, p = 0.0216), cardiac death (97.4+/-0.9 vs 91.9+/-1.4%, p = 0.0042), AMI (98.7+/-0.5 vs 94.2+/-1.2%, p = 0.0034), AMI in a grafted area (98.9+/-0.5 vs 94.7+/-1.3%, p = 0.0017), cardiac events (95.4+/-1.2 vs 86.8+/-1.8%, p = 0.0026) and any events (88.8+/-2.2 vs 80.7+/-2.1%, p = 0.0124). Cox analysis confirmed that LIMA + SVGs was a risk factor independent of lower freedom from all the above-mentioned events.

Conclusions: Double mammary artery in patients < 70 years who had a first time myocardial revascularization gives a better clinical outcome even 10 years after the operation.