Summary

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[1] 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[2] 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[3] 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.