Risk Factors for Restenosis Following Carotid Endarterectomy in Patients with Full Collapse Carotid Near-Occlusion.

Objective: To investigate the postoperative efficacy of carotid endarterectomy for the treatment of near-total occlusion lesions at the bifurcation of the carotid artery and/or origin of the internal carotid artery, accompanied by distal vascular collapse, and factors influencing postoperative restenosis.

Methods: This retrospective cohort study enrolled 380 patients diagnosed with severe carotid artery stenosis. All patients underwent carotid endarterectomy at the First Affiliated Hospital of Zhengzhou University from March 2015 to 2023. Clinical data from these patients-296 males and 84 females, median age 66 years-were obtained. Patients were stratified into three groups based on carotid artery stenosis: severe stenosis (n=234), near-occlusion without collapse (n=70), and near-total occlusion (n=76). A comparative analysis was conducted regarding general characteristics, surgical data, and postoperative complications. Transcranial Doppler ultrasound data were obtained from 65 patients with near-total occlusion. They were divided into two groups based on the occurrence of restenosis postoperatively: restenosis (n=7) and no-restenosis (n=58). A comparative analysis was conducted to determine the disparities in systolic peak-flow and diastolic end-flow velocities between these two groups before and after surgical intervention. A 2-year follow-up study was conducted for 366 patients. Cox univariate and multivariate regression analyses were performed to identify factors associated with postoperative restenosis in patients with near-total occlusion. Kaplan-Meier survival curves were plotted for patients without restenosis and stroke, and Log-rank tests were used to compare survival curves.

Results: Surgical intervention was completed in all patients. During the perioperative period, 29 cerebral infarctions, seven high perfusion syndrome, four cerebral hemorrhage, 17 postoperative restenosis, and 14 deaths occurred. Among the patients who completed the 2-year follow-up, no new cases of cerebral infarction or postoperative restenosis were observed. Statistically significant differences were observed in preoperative cerebral infarction (χ²=8.953, P=0.011) and postoperative restenosis (P=0.005). Subgroup analysis revealed that the presence of middle cerebral artery disease (hazard ratio=13.393, 95% confidence interval: 1.321-135.772, P=0.028) was an independent risk factor for restenosis in patients with near-total occlusion lesions. Survival analysis demonstrated that the cumulative incidence of restenosis and stroke did not exhibit a significant difference (Log rank χ²=7.950, P=0.019; Log rank χ²=0.453, P=0.797, respectively).

Conclusion: In comparison with patients diagnosed with severe carotid artery stenosis and near-occlusion without collapse, those with carotid near-total occlusion lesions demonstrated an increased propensity for restenosis following carotid endarterectomy. Furthermore, serial lesions accompanied by concomitant intracranial middle cerebral artery lesions emerged as an independent risk factor for postoperative restenosis.