Bilateral internal mammary artery for multi-territory myocardial revascularization: long-term follow-up of pedicled versus skeletonized conduits.

Objectives: The aim of this study was to evaluate 17-year actual clinical outcomes of patients undergoing coronary artery bypass graft (CABG) using skeletonized versus pedicled bilateral internal mammary arteries (BIMAs).

Methods: From September 1991 to June 1996, 548 consecutive patients underwent CABG for multivessel disease using BIMA. After propensity matching, 350 patients were enrolled: 175 patients with skeletonized BIMA (Group S) and 175 with pedicled BIMA (Group P). The two groups were adequately comparable. Composite end-point: deaths, new revascularization and new myocardial infarctions were defined as 'events'.

Results: Group S provided a higher rate of total arterial myocardial revascularization (94.3 vs 82.9%, P 0.001) with a higher average number of arterial anastomoses (3.1 ± 0.8 vs 2.7 ± 0.8, P < 0.001) and BIMA anastomoses (2.5 ± 0.3 vs 2.1 ± 0.3, P < 0.001). In Group S, the incidence of sequential grafts was higher (37.7 vs 17.7%, P < 0.001). The rate of sternal wound healing problems was lower (1.7 vs 7.4%, P = 0.010). Thirty-day mortality and morbidity were similar. The median survival time of survivors was 17.8 years (min-max = 17.0-21.5); 17.3 (17.0-18.0) in Group S vs 19.1 (18.1-21.5) in Group P, P < 0.001. Seventeen-year actual outcomes were better in Group S: deaths (8.7 vs 27.9%, P < 0.001), cardiac deaths (4.7 vs 13.4%, P = 0.005), cardiac events (10.5 vs 22.1%, P = 0.003), new revascularization (2.9 vs 8.7%, P = 0.021) and events (15.1 vs 36.1%, P < 0.001).

Conclusions: Skeletonization of BIMA allows one to achieve a higher rate of arterial grafting and better outcome if compared with pedicled BIMA.