Clinical and Angiographic Outcomes of Bilateral Internal Thoracic Artery Revascularization: In Situ vs Free Grafts

BACKGROUND Bilateral internal thoracic artery (ITA) grafting is associated with improved long-term outcomes; however, the appropriate graft configuration remains controversial. We compared the long-term outcomes of different graft configurations. METHODS Between 2009 and 2015, 1171 patients underwent isolated bilateral ITA grafting for left- sided complete revascularization at 4 Japanese cardiac surgery centers: underwent in situ left ITA to the left anterior descending artery plus in situ right ITA to the left circumflex artery (LR group, n = 278), in situ right ITA to the left anterior descending artery plus in situ left ITA to the left circumflex artery (RL group, n = 665), and in situ left ITA to the left anterior descending artery plus free right ITA to the left circumflex artery (free group, n = 228). Major adverse cardiovascular events (MACEs), including mortality, myocardial infarction and revascularization, and ITA patency, were compared. RESULTS Among the 3 groups, the free group showed significantly lower MACEs and overall mortality rates (P < .001). Nonfatal myocardial infarction and revascularization rates showed no marked differences among the groups. A weighted analysis revealed a decreased risk of MACEs and death in the free group. No marked difference was observed in the patency of the ITA anastomosed to the left anterior descending artery. Patency of the ITA grafted to the circumflex artery in the LR group was significantly lower relative to the other groups. Using a free right ITA grafted to the circumflex artery reduced the risk of graft failure. CONCLUSIONS The free right ITA configuration for left-sided revascularization might have better long-term outcomes and significantly better patency than other grafts.