Bilateral sceletonized internal mammary arteries for myocardial revascularization in elderly patients.

Background: Bilateral internal mammary arteries (BIMAs) as the most advanced surgical option for coronary artery bypass grafting (CABG) are usually recommended for younger patients without traditional risk factors. This study compares outcomes in propensity score-matched patients aged over 70 years who received BIMAs versus those who received a single internal mammary artery (SIMA).

Methods: From 2013 to 2024, 8123 patients underwent primary CABG for multivessel coronary artery disease at our institution. BIMA grafting was performed in 1233 patients (15.17%), with in situ BIMA grafting in 290 patients (3.57%). For in situ BIMA group, the right internal mammary artery was used to revascularize the right coronary artery, while the left internal mammary artery was utilized for the left anterior descending artery. BIMA patients aged over 70 years (n = 79) were compared with SIMA patients (n = 79) using propensity score matching. Primary outcome was all-cause mortality at 30 days and 8 years. Secondary outcomes included length of hospital stay, incidence of postoperative major adverse cardiovascular and cerebrovascular events, sternal wound infection and the need for subsequent percutaneous revascularization.

Results: There was no difference in immediate postoperative primary and secondary outcomes. Mean follow-up was 8.3 ± 1.0 years with an 8-year freedom from death of 67.08% ± 1.1% in the BIMA group versus 58.22% ± 0.9% in the SIMA group (P < 0.05).

Conclusions: BIMAs as in situ grafts can be successfully used in CABG for patients aged 70 years and older. Consequently, the refined techniques for constructing internal mammary artery grafts used in this study challenge traditionally accepted limitations regarding the use of BIMAs.