Bilateral internal thoracic artery grafting: in situ or composite?

Bilateral internal thoracic artery (BITA) grafting is considered a superior choice for coronary artery bypass grafting (CABG). While the 10-year outcomes of BITA grafting from the recent Arterial Revascularization Trial (ART) are still pending, numerous observational studies have demonstrated the advantages of BITA grafting. These include better long-term graft patency and freedom from arteriosclerosis, in addition to higher survival rate compared to CABG using only the left internal thoracic artery (ITA). The different BITA configurations are in situ and composite—the choice of optimal grafting configuration is challenging. Patient factors such as coronary anatomy, presence of a diseased ascending aorta and the potential need for a future redo sternotomy will influence the choice of the grafting strategy. In situ BITA grafting is associated with excellent clinical outcomes and has been extensively described in the literature. However, uncertainties remain regarding the ideal in situ configuration and design. Composite BITA grafting is the other option that maximizes right ITA (RITA) utilization. In this configuration, the RITA is able to reach the distal circumflex and right coronary artery branches. This approach decreases the need for a third graft conduit.