Bilateral internal thoracic artery grafting: Does graft configuration affect outcome?

Background: Despite evidence that bilateral internal thoracic arteries (ITAs) improve long-term survival after coronary artery bypass grafting (CABG), uptake of this technique remains low. We directly compared bilateral ITA graft configurations and examined long-term outcomes. Methods: We reviewed 762 patients who underwent CABG using bilateral ITA grafts at our institution between 1997 and 2014. The outcomes were mortality and a composite revascularization end point defined as need for percutaneous coronary intervention or repeat CABG. Adjusted subgroup analyses were performed using propensity score-adjusted Cox proportional hazards modeling. Results: The cohort was divided into 4 groups: in situ (left ITA [LITA] anastomosed to the left anterior descending artery [LAD] with in situ right ITA [RITA] anastomosed to the left coronary circulation [239 patients]); in situ LITA-LAD and in situ RITA-right coronary circulation (239 patients); in situ RITA-LAD with in situ LITA-left coronary circulation (185 patients); and in situ LITA-LAD with a free RITA as a composite graft with inflow from the LITA or a saphenous vein graft (99 patients). Over a median follow-up of 1128 days, there were 47 deaths, 58 late percutaneous coronary interventions, and 7 repeat CABG procedures. Unadjusted Kaplan-Meier analysis revealed a difference in need for repeat revascularization among the 4 groups (log rank P = .049). However, after statistical adjustment, graft configuration was not an independent predictor of repeat revascularization or death. Conclusions: Bilateral ITA graft configuration has no independent effect on need for repeat revascularization or long-term survival. Therefore, the simplest technique, determined by individual patient characteristics, should be selected.