Refining the indications for carotid endarterectomy in patients with symptomatic carotid stenosis:: A systematic review

Objective: The purpose of this study was to summarize the existing literature on the efficacy of carotid endarterectomy in patients with ipsilateral symptomatic carotid stenosis. Methods: Database searching, relevance assessment, methodologic quality assessments, and data extraction were all performed in duplicate with prespecified criteria. Results: Twenty-three publications were identified from the North American Symptomatic Carotid Endarterectomy Trial, the European Carotid Surgery Trial, and the Veterans Affairs Cooperative Studies Program. Stenosis was reported as measured in the North American Symptomatic Carotid Endarterectomy Trial. In patients with >70% stenosis, carotid endarterectomy was associated with a pooled relative risk reduction of 48% (95% confidence interval [CI], 27% to 73%) and an absolute risk reduction of 6.7% (95% CI, 3.2% to 10%) for the outcome of death or major disability from stroke. This translates into a number needed to treat of 15 (95% CI, 10 to 31). For patients with 50% to 69% stenosis, the benefit of surgery was less and the confidence intervals were wider. A relative risk reduction of 27% (95% CI, 5% to 44%), an absolute risk reduction of 4.7% (95% CI, 0.8% to 8.7%), and a number needed to treat of 21 (95% CI, 11 to 125) were observed in this group. The patients with the lowest degrees of stenosis (<50%) were harmed by the intervention (number needed to harm, 45). Increasing degree of stenosis, increasing age, male sex, the presence of other medical risk factors, and the presence of hemispheric rather than retinal antecedent events were factors that increased the benefits from surgery. Conclusion: Carotid endarterectomy reduced death or major disability from stroke in patients with >50% symptomatic stenosis. To maximize the benefits of surgery, careful preoperative risk assessment and the maintenance of low rates of major perioperative complications are mandatory.