Impact of Head and Neck Radiation on Long-term Outcomes After Carotid Revascularization

Radiation-induced carotid artery stenosis is a well-described phenomenon seen after treatment for head and neck cancer. Previously published literature suggests that compared to atherosclerotic disease, radiation-induced carotid artery stenosis may result in poorer long-term outcomes and early restenosis. The study aims to evaluate the effect of radiation on long-term outcomes after various carotid revascularization techniques using a multicenter registry database. Patients in the Society for Vascular Surgery Vascular Quality Initiative registry for carotid artery intervention (carotid endarterectomy, CEA; transfemoral carotid artery stenting, CAS; transcarotid artery revascularization, TCAR), who are 65 years or older were included in the study. Vascular Quality Initiative Vascular Implant Surveillance and Interventional Outcomes Network Medicare-linked database was used to obtain long-term procedure-specific outcomes. Primary end points were 3-year death, stroke, and reintervention. We performed propensity matching between patients with prior radiation and those without. Kaplan-Meier analysis and a multivariate logistic regression model were used to analyze the outcome variables. There were 1244 patients with prior radiation and 54,925 patients without prior radiation. Prior radiation group was more likely to be male (71.9% vs 60.3%; P ≤ .01), more likely to receive a stent (47.5% vs 13.5%; P < .01), and more likely to be on P2Y12 inhibitor (55.2% vs 38.3%; P < .01). Propensity matching was performed on 1223 patients (CEA, n = 655; TCAR, n = 292; CAS, n = 287). There were no significant differences in 30-day outcomes for death, stroke, or major adverse cardiovascular events for all three procedures (Table). The prior radiation group had higher rates of cranial injury (3.7% vs 1.8%; P = .04) and 90-day readmission (23.5% vs 18.3%; P = .01) after CEA. For long-term outcomes, prior radiation significantly increased mortality risk for CEA and CAS (hazard ratio [HR], 1.77; 95% confidence interval [CI], 1.38-2.27 and HR, 1.56; 95% CI, 1.02-2.36, respectively). The 3-year risk of stroke for CEA in radiated patients was also significantly higher (HR, 1.47; 95% CI, 1.03-2.09) compared to nonradiated patients. Prior radiation did not significantly affect death and stroke in patients undergoing TCAR. Prior radiation also did not impact the rates of short and long-term reintervention after CEA, CAS, or TCAR. Prior head and neck radiation significantly increases the risk for mortality and stroke for CEA and the risk for mortality after CAS. Long-term outcomes for TCAR are not significantly affected by prior radiation. TCAR may be the preferred treatment modality for patients with radiation-induced carotid stenosis.TableHR95% CIP valueCEA Death1.771.38-2.27<.01 Stroke1.471.03-2.09.03 Reintervention1.260.87-1.82.21CAS Death1.561.02-2.36.04 Stroke0.910.56-1.46.68 Reintervention1.710.86-3.38.13TCAR Death1.100.60-2.03.76 Stroke1.470.66-3.31.35 Reintervention0.980.54-1.79.96All Death1.371.12-1.68<.01 Stroke0.980.75-1.27.85 Reintervention1.240.94-1.64.13CAS, Carotid artery stenting; CEA, carotid endarterectomy; CI, confidence interval; HR, hazard ratio; TCAR, transcarotid artery revascularization. Open table in a new tab