Long-term outcomes after carotid artery stenting of patients with prior neck irradiation or surgery

Background: Carotid artery stenting (CAS) is often performed in patients with carotid artery stenosis who have relative contraindications to carotid endarterectomy (CEA), including hostile neck anatomy (e.g., history of neck irradiation or prior surgery). We examined the impact of hostile neck anatomy on long-term outcomes after CAS. Methods: All carotid artery stent procedures performed at two institutions from 2006 to 2016 were reviewed. Routine duplex carotid ultrasound was used to assess target lesion restenosis at regular intervals. The primary endpoint was rates of target lesion revascularization (TLR). Secondary endpoints included peri-procedural outcomes, restenosis, stroke, major adverse cardiovascular and cerebrovascular events (MACCE), and mortality during long-term follow up. A Cox proportional hazard model was developed to determine the association between hostile neck anatomy and outcome after CAS. Results: 304 CAS procedures were performed in 268 patients (hostile neck = 53, non-hostile neck = 215). Patients with hostile neck anatomy were more likely to have a history of smoking and history of prior carotid artery revascularization. There were no differences in peri-procedural outcomes including stroke. During follow-up to five years there were no significant differences in rates of TLR (1.4% vs. 3.8%, P = 0.25), restenosis (1.9% vs. 5.1%, P = 0.31), MACCE (26% vs. 18%, P = 0.15), ipsilateral stroke (7.5% vs. 2.8%, P = 0.101), or mortality (13% vs. 14%, P = 0.89). Hostile neck anatomy was not associated with significantly increased 5-year TLR rates in the Cox regression analysis (HR = 2.64; 95% CI: 0.44-15.83; P = 0.289). Conclusions: Despite greater comorbidities, patients with hostile neck anatomy and carotid artery stenosis have favorable outcomes after carotid artery stenting.