Left-Sided Complete Revascularization With Bilateral Internal Thoracic Arteries in Patients With Diabetes

Background: Reports are few on the long-term patency of bilateral internal thoracic artery (BITA) grafts in patients with diabetes. We evaluated the relationship between the long-term patency of BITAs and the clinical outcomes in diabetes. Methods: We retrospectively identified 569 patients (321 with diabetes, 248 without diabetes) who underwent isolated BITA grafting for left-sided complete revascularization at our institution from 2000 to 2015. The primary end point was the incidence of major adverse cardiovascular events comprising death, re-revascularization, and myocardial infarction. The secondary end point was the patency of the BITAs. Results: No differences were found in the major adverse cardiovascular event rate (10-year: diabetic group, 33.7%; nondiabetic group, 22.3%; p = 0.15) or overall mortality rate (24.0% versus 12.2%, p = 0.066) between the patients with and without diabetes. The incidence of cardiac death (3.3% versus 1.8%, p = 0.80) or re-revascularization and myocardial infarction (11.4% versus 11.8%, p = 0.67) was similar between the groups. The patency of free internal thoracic artery (ITA) grafts to the left circumflex artery was associated with greater patency in patients with diabetes than in patients without diabetes (4 years: 99.3% versus 95.5%, p = 0.049); the patency of other ITA grafts did not differ between the groups. Conclusions: All-cause death, re-revascularization, and myocardial infarction showed no differences between patients with and without diabetes who underwent left-sided revascularization with the BITAs. Although diabetes did not affect the patency of the ITA, free ITA grafts to the left circumflex artery showed good long-term patency in patients with diabetes.