Background: Total arterial coronary revascularization for three vessel disease can be achieved with a second arterial conduit joined to the left internal mammary artery as a Y graft, using either a radial artery (RAY) or second mammary artery (BIMAY).
Methods: Patients receiving total arterial revascularization for three coronary territory disease were identified from two cardiac surgical databases (Sydney and Melbourne) using Society of Thoracic Surgeons-based definitions. BIMAY patients underwent surgery between 1994 and 2009, mostly using an age-limited protocol, while RAY patients underwent surgery between 1996 and 2003 without age limits. All-cause mortality was acquired from the national death registry and survival estimated by the Kaplan-Meier method. Propensity score matching was performed using 13 variables. Due to the age imbalance between groups, the primary comparison was performed for age ≤66 years.
Results: Overall, 1,896 patients received RAY and 720 patients received BIMAY. Older age at surgery was the strongest independent predictor for mortality with a hazard ratio of HR 2.06, 95%CI 1.93, 2.22, P<0.001. After propensity score matching, we identified 299 pairs of patients ≤66 years with no preoperative or operative differences and similar age at surgery, RAY 56.4±7.0 vs. BIMAY 56.4±6.8 years, P=0.96. The RAY group had 4.0±0.9 grafts and the BIMAY group had 3.9±0.9, P=0.814. All-cause mortality was not different, with the proportion surviving at 15 years at 74.9% for RAY vs. 76.2% for BIMAY (P=0.211).
Conclusions: Survival was not different between RAY and BIMAY for total arterial revascularization of three coronary territory bypass grafting.
