Graft Patency and Clinical Outcomes in Patients With Radial Artery Grafts Previously Instrumented for Cardiac Catheterization

BACKGROUND: While transradial access is favored for cardiac catheterization, the radial artery (RA) is increasingly preferred for coronary artery bypass grafting. Whether the RA is suitable for use as a graft following instrumentation for transradial access remains uncertain. METHODS: Consecutive patients from 2015 to 2019 who underwent coronary artery bypass grafting using both the left and right RAs as grafts were included. Instrumented RAs underwent careful preoperative assessment for suitability. The clinical analysis was stratified by whether patients received an instrumented RA graft (instrumented versus noninstrumented groups). Eligible patients with both instrumented and noninstrumented RAs underwent computed tomography coronary angiography to evaluate graft patency. The primary outcome was a within-patient paired analysis of graft patency comparing instrumented to noninstrumented RA grafts. RESULTS: Of the 1123 patients who underwent coronary artery bypass grafting, 294 had both the left and right RAs used as grafts and were included. There were 126 and 168 patients in the instrumented and noninstrumented groups, respectively. Baseline characteristics and perioperative outcomes were comparable. The rate of major adverse cardiac events at 2 years following coronary artery bypass grafting was 2.4% in the instrumented group and 5.4% in the noninstrumented group (hazard ratio, 0.44 [95% CI, 0.12-1.61]; P=0.19). There were 50 patients included in the graft patency analysis. At a median follow-up of 4.3 (interquartile range, 3.7-4.5) years, 40/50 (80%) instrumented and 41/50 (82%) noninstrumented grafts were patent (odds ratio, 0.86 [95% CI, 0.29-2.52]; P>0.99). No significant differences were observed in the luminal diameter or cross-sectional area of the instrumented and noninstrumented RA grafts. CONCLUSIONS: There was no evidence found in this study that RA graft patency was affected by prior transradial access, and the use of an instrumented RA was not associated with worse outcomes in the exploratory clinical analysis. Although conduits must be carefully selected, prior transradial access should not be considered an absolute contraindication to the use of the RA as a bypass graft.