Neck radiation is not associated with increased risk of perioperative adverse events after transcarotid artery revascularization or transfemoral carotid artery stenting

Objective: It is unclear whether patients with prior neck radiation therapy (RT) are at high risk for carotid artery stenting (CAS). We aimed to delineate 30-day perioperative and 3-year long-term outcomes in patients treated for radiation-induced stenotic lesions by the transfemoral carotid artery stenting (TFCAS) or transcarotid artery revascularization (TCAR) approach to determine comparative risk and to ascertain the optimal intervention in this cohort. Methods: Data were extracted from the Vascular Quality Initiative CAS registry for patients with prior neck radiation who had undergone either TCAR or TFCAS. The Student t-test and the χ² test were used to compare baseline patient characteristics. Multivariable logistic regression and Cox Hazard Proportional analysis were used to compare perioperative and long-term differences between patients with and without prior neck radiation following TCAR and TFCAS. Kaplan-Meier estimator was used to determine the incidence of 3-year adverse events. Results: A total of 72,656 patients (TCAR, 40,879; TFCAS, 31,777) were included in the analysis. Of these, 4151 patients had a history of neck radiation. Patients with a history of neck radiation were more likely to be younger, white, and have fewer comorbidities than patients with no neck radiation history. After adjustment for confounding factors, there was no difference in relative risk of 30-day perioperative stroke (P = .11), death (P = .36), or myocardial infarction (MI) (P = .61) between TCAR patients with or without a history of neck radiation. The odds of stroke/death (P = .10) and stroke/death/MI (P = .07) were also not statistically significant. In patients with prior neck radiation, TCAR had lower odds for in-hospital stroke/death/MI (odds ratio, 0.59; 95% confidence interval [CI], 0.35-0.99; P = .05) and access site complications than TFCAS. At year 3, patients with prior neck radiation had an increased hazard for mortality after TCAR (hazard ratio [HR], 1.24; 95% CI, 1.02-1.51; P = .04) and TFCAS (HR, 1.33; 95% CI, 1.12-1.58; P = .001). Patients with prior neck radiation also experienced an increased hazard for reintervention after TCAR (HR, 2.16; 95% CI, 1.45-3.20; P < .001) and TFCAS (HR, 1.67; 95% CI, 1.02-2.73; P<.001). Conclusions: Patients with prior neck radiation had a similar relative risk of 30-day perioperative adverse events as patients with no neck radiation after adjustment for baseline demographics and disease characteristics. In these patients, TCAR was associated with reduced odds of perioperative stroke/death/MI as compared with TFCAS. However, patients with prior neck radiation were at increased risk for 3-year mortality and reintervention.