Effect of the Proximal Anastomosis Site on Mid-term Radial Artery Patency in Off-pump Coronary Artery Bypass

Objectives: The purpose of this study was to evaluate mid-term patency and clinical outcomes according to the proximal anastomosis site after off-pump coronary artery bypass using the radial artery (RA).

Methods: From January 2001 to December 2015, 1124 patients who underwent isolated off-pump coronary artery bypass using the RA were reviewed and divided into 2 groups: the composite Y-graft (n = 1014, Y group) and aortocoronary graft (n = 110, Aorta group). Graft patency was assessed by computed tomography or coronary angiography.

Results: Patients receiving Y-grafts had a greater number of RA anastomoses (1.79 ± 0.68 per patient vs 1.40 ± 0.51 per patient, P < 0.001), more sequential grafts (55.6% vs 37.3%, P < 0.001) and a higher incidence of total arterial revascularization (77.9% vs 54.5%, P < 0.001). Postoperative graft patency at a mean of 3.1 ± 3.5 years was assessed in 1944 distal RA anastomoses (Y group: 1811, Aorta group: 133). No significant differences were observed in RA graft patency rate (P = 0.705), overall survival (P = 0.987) and major cardiac event-free survival (P = 0.830) between groups. Multivariable analysis demonstrated that the independent predictors of graft occlusion were age [hazard ratio (HR) 1.025, confidence interval (CI) 1.007-1.044; P = 0.007], female gender (HR 1.391, CI 1.007-1.924; P = 0.047), target of the right coronary artery territory (HR 2.135, CI 1.347-3.382; P = 0.001) and target vessel stenosis ≥90% (HR 0.478, CI 0.291-0.785; P = 0.004). The proximal anastomosis site was not significantly associated with graft occlusion (P = 0.705).

Conclusions: When target vessel territory and stenosis are appropriately considered, the RA as a secondary conduit can be effectively used for myocardial revascularization, regardless of the proximal anastomosis site.