Clinical Question

Is carotid artery stenting more effective than endarterectomy in patients with carotid artery stenosis?

Bottom Line

These two randomized trials, one with short-term outcomes and the other with five-year outcomes, demonstrate that carotid artery stenting results in more frequent strokes (clinical and radiographically detected) than carotid endarterectomy (CEA). However, the rate of fatal and disabling strokes is comparable. (Level of Evidence = 2b–)

Synopsis

These two studies, one from the Czech Republic (N = 150) and the other multinational (the International Carotid Stenting Study [ICSS]; N = 1,700), compared CEA with carotid artery stenting. The investigators used comparable methods (concealed allocation, only outcome assessors were blinded) and recruited adults with carotid stenosis. The Czech researchers evaluated patients with at least 70% stenosis before intervention, at 24 hours, and again 30 days later. The ICSS researchers, who evaluated patients with at least 50% stenosis, provided five-year outcome data. Although the authors of both studies report on functional outcomes (such as the modified Rankin scale), the Czech researchers report on magnetic resonance imaging–detected lesions and cognitive function, and the ICSS investigators report stroke rates.

In the Czech study, new infarcts were detected on magnetic resonance imaging in 49% of stented patients compared with 25% of the patients treated with CEA (number needed to treat to harm [NNTH] = 4). Most of these were silent as only two stented patients and one CEA-treated patient had symptoms. The authors reported no differences in any of the cognitive measures.

In the ICSS, the rate of fatal strokes was similar (6.4% vs. 6.5%) in each group. However, the rate of all strokes was 4.4% higher in the stented patients after the first year and 5.8% higher after the fifth year of follow-up (NNTH = 38 for the first year and 500 for the fifth year). Additionally, during the first year of follow-up, the stented group had 2.6% more deaths, but by five years, the death rate was similar for each group. The authors also report that the long-term functional outcomes were similar for each group.

Study design: Randomized controlled trial (nonblinded)

Funding source: Industry plus government

Allocation: Concealed

Setting: Inpatient (any location) with outpatient follow-up

References: KulihaMRoubecMProcházkaVet alRandomized clinical trial comparing neurological outcomes after carotid endarterectomy or stenting. Br J Surg2015; 102( 3): 194– 201.

BonatiLHDobsonJFeatherstoneRLet alInternational Carotid Stenting Study investigatorsLong-term outcomes after stenting versus endarterectomy for treatment of symptomatic carotid stenosis: the International Carotid Stenting Study (ICSS) randomised trial. Lancet2015; 385( 9967): 529– 538.