Background: The use of the bilateral internal mammary arteries has been reserved mainly for younger and low risk patients.
Aim: To assess the safety and efficacy of BIMA grafting in older patients (≥ 70 years).
Methods: We reviewed the records of all consecutive patients ≥ 70 years old who underwent coronary artery bypass surgery with a BIMA graft in our institute over a 2 year period. Demographic data, operative data, perioperative morbidity and mortality were recorded. Findings were compared with a matched-size group of patients who underwent CABG with a left internal mammary artery graft to left anterior descending artery.
Results: The study sample included 136 patients, of whom 68 underwent BIMA grafting and 68 LIMA grafting. Baseline demographic and clinical characteristics were similar in the two groups. There was no significant difference in operative mortality between the BIMA and LIMA groups (1.5% vs. 0%, P = 0.3) or in mortality during follow-up at a mean of 16 months (4.4% vs. 2.9%, P = 0.4, respectively). There was no difference between the groups in the incidence of perioperative complications, re-admission and re-intervention rates during follow-up. Significant between-group differences were noted for mean cardiopulmonary bypass time (93.2 ± 34.7 BIMA vs. 108.8 ± 40.7 LIMA min, P = 0.02) and for red blood cell transfusion (1.9 ± 1.9 vs. 4.3 ± 2.8 packed cells/patient, P < 0.001).
Conclusions: The performance of mainly arterial revascularization with BIMA grafting in patients 70 years or older is as safe as LIMA grafting, with the added advantage of being a better conduit than saphenous vein graft, requiring fewer blood transfusions, and shorter cardiopulmonary bypass time.