Risk of early stroke recurrence and procedural stroke or death in carotid near occlusion patients scheduled for carotid endarterectomy

BACKGROUND: Carotid near occlusion (NO) refers to distal internal carotid artery (ICA) narrowing caused by proximal carotid stenosis (CS). Stroke risk and optimal management of NO remain controversial. Our aim was to determine the prevalence of NO severities, rates of preoperative ischemic cerebrovascular events (iCVEs), 30-day procedural stroke and death, and hyperperfusion syndrome in patients with NO in a prospective CS cohort undergoing carotid endarterectomy (CEA). METHODS: We reanalyzed posthoc CTAs from 443 symptomatic and asymptomatic CS patients. Subtle NO (s-NO) was defined as a 1.0-mm difference in distal luminal diameter between ipsilateral and contralateral ICA. NO with full collapse (fc-NO) was defined as ≤2.0 mm and/or an ipsilateral-to-contralateral ICA diameter ratio ≤0.42. Conventional stenosis was defined as CS >50% using NASCET criteria. Rates of preoperative iCVEs and 30-day procedural stroke and death were compared between s-NO, fc-NO, and conventional stenosis. RESULTS: NO occurred in 143 (32%) patients: 124 (87%) s-NO and 19 (13%) fc-NO. NO was not significantly associated with increased preoperative iCVEs (7.6% vs 13%, OR 1.82, 95%Cl 0.96-3.47) or procedural stroke or death (5.6% vs 3.3%, OR 1.73, 95%Cl 0.67-4.50) compared with conventional stenosis. After CEA, hyperperfusion syndrome was frequent in NO patients (7.0% vs 2.7%, OR 2.8, 95% CI1.1-7.1). One patient developed fatal hyperperfusion-related intracranial hemorrhage. CONCLUSION: CTA-detected NO is common, particularly in subtle forms, and important for stenosis assessment and management. Unlike earlier studies, NO was not associated with increased preoperative or procedural stroke or death, but hyperperfusion syndrome after CEA was more frequent.