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

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).

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'.

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).

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