Does the use of an in situ or Y-configuration for bilateral internal thoracic arteries influence long-term survival, patency or repeat revascularization in coronary bypass surgery?

A best evidence topic was constructed according to a structured protocol. The question addressed was whether the configuration of bilateral internal thoracic arteries (BITAs) influences survival, patency or repeat revascularization in patients undergoing coronary artery bypass grafting. Five hundred and seventy-one papers were found using the reported searches, of which 8 represented the best evidence to answer the clinical question. One systematic review, 4 randomized trials and 3 observational studies were selected. The authors, date, journal, study type, population, main outcome measures and results are tabulated. All 4 prospective randomized trials found no significant difference in graft patency or mortality when comparing Y-graft and in situ configurations. Three of the 4 randomized trials found no difference in major adverse cardiovascular and cerebrovascular events or repeat revascularization at follow-up. An exception was Glineur et al. (Bilateral internal thoracic artery configuration for coronary artery bypass surgery: a prospective randomized trial. Circ Cardiovasc Interv 2016;9:7), who found that the Y-configuration resulted in lower rates of major adverse cardiovascular and cerebrovascular events. All 3 observational studies reviewed found no alteration in survival, cardiac events or repeat revascularization between in situ and Y-graft BITA configurations. One systematic review found similar outcomes with respect to mortality, cardiac events and repeat revascularization with in situ and composite BITA. In summary, existing literature demonstrates no difference in clinical outcomes between composite and in situ graft configurations. Furthermore, the configuration of BITA does not affect mortality, graft patency or repeat revascularization.