Objectives: Carotid artery stenting (CAS) is an alternative to carotid endarterectomy (CEA) for treating carotid artery stenosis. We conducted a systematic review and meta-analysis of the clinical trials to date comparing these two procedures to determine their relative safety and efficacy.
Methods: Searches of the Cochrane Controlled Trials Register, MEDLINE, and EMBASE identified two cohort studies and eight randomized, controlled trials (RCTs) comparing CEA and CAS. Meta-analysis was performed for the primary outcome of 30-day stroke or death, using an intention-to-treat analysis. Between-trial heterogeneity was assessed using the chi2 test, and fixed-effects models were used to pool estimates in the absence of heterogeneity. Meta-regression was conducted to investigate potential effect differences by patient, intervention, and trial characteristics. To evaluate the effect of study design and inclusion criteria, sensitivity and subgroup analyses were performed.
Results: Ten trials encompassing 3580 patients were analyzed. Patients who underwent CAS had a higher risk of 30-day stroke/death relative to patients who underwent CEA (risk ratio [RR], 1.30; 95% CI, 1.01-1.67). Meta-analysis and meta-regression demonstrated no between-trial heterogeneity. Sensitivity analysis of only RCTs showed similar higher risk for stroke/death (RR, 1.38; 95% CI, 1.06-1.79) in CAS patients. Subgroup analysis of trials enrolling only symptomatic patients showed higher risk of 30-day stroke/death (RR, 1.63; 95% CI, 1.18-2.25), but trials enrolling both symptomatic and asymptomatic patients showed no significant differences (RR, 0.89; 95% CI, 0.59-1.35).
Conclusions: Meta-analysis of trials to date shows CAS is associated with higher 30-day risk of stroke/death compared with CEA. Thus, for the patient at average surgical risk, the role of CAS is unproven, especially for symptomatic patients. And for the patient at high surgical risk, the role of any intervention is uncertain in the setting of competing comorbidities. The results of ongoing clinical trials in this area will likely provide additional evidence to support treatment choices for carotid artery stenosis.