Level 2: Mid-level evidence
Stenting may be an alternative to open endarterectomy for the treatment of carotid artery stenosis. The Endarterectomy versus Angioplasty in Patients with Symptomatic Severe Carotid Stenosis (EVA-3S) trial compared these two procedures in 527 adults with hemispheric or retinal transient ischemic attack or nondisabling stroke within 120 days and carotid artery stenosis 60%-99% (N Engl J Med 2006;355:1660-1671). The only significant baseline difference was that 1.2% of the endarterectomy group had contralateral carotid occlusion, compared with 5% of the stenting group. The trial, which was publicly funded, was stopped early due to clinically relevant differences.
At 30 days, carotid endarterectomy (compared with carotid artery stenting) was associated with lower incidences of nonfatal stroke (2.7% vs. 8.8%, P =.004, NNT 17) and combined outcome of stroke of any type or death (3.9% vs. 9.6%, P =.01, NNT 18), decreased bradycardia or hypotension (0% vs. 4.2%, P <.01, NNT 24), and increased cranial-nerve injury (7.7% vs. 1.1%, P <.001, NNH 15).
There were no significant differences in rates of death (1.2% vs. 0.8%), combined outcome of any disabling stroke or death (1.5% vs. 3.4%), systemic complications (3.1% vs. 1.9%), or major local complications (1.2% vs. 3.1%). At six months, the rate of any stroke or death was 6.1% with carotid endarterectomy compared with 11.7% with carotid artery stenting (P =.02, NNT 18).
Another trial concluded that noninferiority of carotid stenting could not be established (Lancet. 2006;368:1239-1247). The Stent-Supported Percutaneous Angioplasty of the Carotid Artery vs. Endarterectomy (SPACE) trial included 1,200 patients with amaurosis fugax, hemispherical transient ischemic attack or complete stroke within 180 days, and ipsilateral carotid artery stenosis at least 70% on duplex ultrasound or using European Carotid Surgery Trial criteria (or at least 50% using NASCET criteria).
Participants were randomized to carotid artery stenting vs. carotid endarterectomy. Intention-to-treat analysis included 1,183 patients; 17 patients withdrew consent before treatment. Comparing carotid artery stenting vs. carotid endarterectomy between randomization and 30 days after treatment, there were no significant differences for any outcome.
Outcomes included the primary end point of ipsilateral stroke or death from any cause (6.84% vs. 6.34%), ipsilateral ischemic stroke (6.51% vs. 5.14%), ipsilateral intracerebral bleeding (0.17% vs. 0.86%), death (0.67% vs. 0.86%), disabling ipsilateral stroke or death (4.67% vs. 3.77%), any stroke (7.51% vs. 6.16%), any stroke or death (7.68% vs. 6.51%), or procedural failure (3.17% vs. 2.05%). The prespecified threshold for noninferiority was not achieved (P =.09).