Background : Recent interest has focused on the use of arterial conduits in diabetic subsets. To date, the long-term benefits of bilateral internal thoracic artery (BITA) grafting in this subgroup remain in question.
Methods : 285 consecutive oral-treated diabetics operated on non-emergent basis (1996- 1998) were compared according to the surgical technique, left-sided skeletonized BITA (n=228) or single ITA-saphenous veins (SITA) (n=57). Patients with chronic lung disease, usually preselected to SITA grafting, were not included.
Results : The respective grafts/patient ratio was 3.11 and 3.20.8 for the SITA and BITA groups (p=NS). Complementary conduits used in the BITA group were gastroepiploic arteries (25%) and saphenous veins (13%). Early outcome was comparable, including the incidence of deep sternal infections (1.8% in both groups). During follow up (range 4-7.5 years, median 5), there were less repeat revascularizations (4.4% vs 12.3%, p=0.025) and major adverse cardiac events (MACE) (11.2% vs 36.8%, p<0.0001) in the BITA group. At 7 years, survival (Kaplan-Meier) (75% vs 59% p=0.006, log-rank), freedom from cardiac-mortality (92% vs 68%, p<0.0001) and freedom from MACE (70% vs 59% p=0.004) were superior in the BITA group. Multivariate analysis identified the use of BITA as a protective factor against the occurrence of late cardiac mortality (OR 0.2) and MACE (OR 0.3); conversely, SITA-saphenous vein arrangements increased the risk by 5-fold (OR 5, CL 1.6-16.6, p=0.005) and 3-fold (OR 3.3, CL 1.5-9, p=0.005), respectively.
Conclusions : Left-sided BITA grafting confers improved long-term survival and event-free survival in oral-treated diabetics. We, therefore, recommended this approach in this diabetic subset.