Stenting versus endarterectomy for treatment of carotid-artery stenosis

Abstract

Background: Carotid-artery stenting and carotid endarterectomy are both options for treating carotid-artery stenosis, an important cause of stroke.

Methods: We randomly assigned patients with symptomatic or asymptomatic carotid stenosis to undergo carotid-artery stenting or carotid endarterectomy. The primary composite end point was stroke, myocardial infarction, or death from any cause during the periprocedural period or any ipsilateral stroke within 4 years after randomization.

Results: For 2502 patients over a median follow-up period of 2.5 years, there was no significant difference in the estimated 4-year rates of the primary end point between the stenting group and the endarterectomy group (7.2% and 6.8%, respectively; hazard ratio with stenting, 1.11; 95% confidence interval, 0.81 to 1.51; P=0.51). There was no differential treatment effect with regard to the primary end point according to symptomatic status (P=0.84) or sex (P=0.34). The 4-year rate of stroke or death was 6.4% with stenting and 4.7% with endarterectomy (hazard ratio, 1.50; P=0.03); the rates among symptomatic patients were 8.0% and 6.4% (hazard ratio, 1.37; P=0.14), and the rates among asymptomatic patients were 4.5% and 2.7% (hazard ratio, 1.86; P=0.07), respectively. Periprocedural rates of individual components of the end points differed between the stenting group and the endarterectomy group: for death (0.7% vs. 0.3%, P=0.18), for stroke (4.1% vs. 2.3%, P=0.01), and for myocardial infarction (1.1% vs. 2.3%, P=0.03). After this period, the incidences of ipsilateral stroke with stenting and with endarterectomy were similarly low (2.0% and 2.4%, respectively; P=0.85).

Conclusions: Among patients with symptomatic or asymptomatic carotid stenosis, the risk of the composite primary outcome of stroke, myocardial infarction, or death did not differ significantly in the group undergoing carotid-artery stenting and the group undergoing carotid endarterectomy. During the periprocedural period, there was a higher risk of stroke with stenting and a higher risk of myocardial infarction with endarterectomy. (ClinicalTrials.gov number, NCT00004732.)

Figure 1. Randomization and Follow-up of the Study Patients

Patients were assessed for eligibility before randomization, but the number of patients assessed is not available, because screening logs were not maintained. CAS denotes carotid-artery stenting, and CEA carotid endarterectomy.

Figure 2. Primary End Point, According to Treatment Group

The primary end point was a composite of stroke, myocardial infarction, or death from any cause during the periprocedural period or ipsilateral stroke within 4 years after randomization. Panel A shows the Kaplan–Meier curves for patients undergoing carotid-artery stenting (CAS) and those undergoing carotid endarterectomy (CEA) in whom the primary end point did not occur, according to year of follow-up. Panel B shows the hazard ratios for the primary end point, as calculated for the CAS group versus the CEA group, according to age at the time of the procedure. The hazard ratios were estimated from the proportional-hazards model with adjustment for sex and symptomatic status. Dashed lines indicate the 95% confidence intervals. Panel C shows the numbers of patients in each age group.