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

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.