Cumulative incidence of restenosis in the endovascular treatment of extracranial carotid artery stenosis: a meta-analysis

Objective To assess the cumulative incidence of restenosis and stroke after stenting for cervical carotid artery stenosis. Methods We reviewed PubMed, ScienceDirect, and Scopus and included all studies reporting restenosis after stenting. The cumulative incidence of restenosis at 6 and 12 months was calculated. We also estimated the cumulative incidence of ipsilateral stroke within 30 days after stenting. Random effect meta-analysis and meta-regression were performed using relevant study level covariates. Sources of heterogeneity were investigated. Results Among 7765 records, 40 studies were selected. 15 943 patients and 16 337 carotid arteries were considered. The overall pooled cumulative incidence of restenosis >50% at 12 months was 5.7% (95% CI 3.8% to 8.6%), >70% at 12 months was 5.2% (95% CI 3.3% to 8.2%), >50% at 6 months was 3.9% (95% CI 2.2% to 6.8%), and ipsilateral stroke within 30 days after stenting was 1.6% (95% CI 1.0% to 2.5%) without association with the use of an embolic protection device. We did not identify any relevant source of heterogeneity of the cumulative incidence of restenosis >50% at 12 months. Mean age explained 80.9% (R 2 =80.9%, p=0.01) of heterogeneities of restenosis >70% at 12 months. The presence of hostile neck explained 53.9% (R 2 =53.9%, p=0.03) of heterogeneities of restenosis >50% at 6 months. Conclusion This meta-analysis showed a low cumulative rate of restenosis at 12 months and ipsilateral stroke within 30 days after stenting. Older patients and those with hostile neck present a lower risk of in-stent restenosis. The use of an embolic protection device was not associated with a lower risk of stroke.