Analysis of EVA-3S Looks at Anatomical and Technical Factors Associated With Stroke or Death During CAS

January 31, 2011—In Stroke, Olivier Naggara, MD, et al published findings from a study that sought to assess the relationships between anatomic and technical factors and the 30-day risk of stroke or death after carotid artery angioplasty and stenting (CAS) in the EVA-3S (Endarterectomy Versus Stenting in Patients with Symptomatic Severe Carotid Stenosis) trial and to perform a systematic review of the literature (2011;42:380–388).

In the study, the investigators included patients from EVA-3S in whom CAS was attempted irrespective of allocated treatment. Two radiologists blinded to clinical data independently assessed the aortic arch and carotid arteries on procedural angiograms. In addition, the investigators performed a systematic review of studies that reported 30-day risk of stroke or death in relation with arterial anatomy and technique. Outcomes were stroke or death and stroke occurring within 30 days of the CAS procedure.

As detailed in Stroke, the investigators reported that 262 patients from EVA-3S fulfilled the inclusion criteria (including one patient initially allocated to surgery and 13 in whom stent insertion failed). Within 30 days after the procedure, 25 (9.5%) patients had a stroke or had died. The risk of stroke or death was higher in patients with internal carotid artery–common carotid artery angulation ≥ 60° (relative risk [RR], 4.96; 2.29–10.74) and lower in those treated with cerebral protection devices (RR, 0.38; 0.17–0.85).

In the systematic review (56 studies; 34,398 patients), the investigators found that the risk of stroke or death was higher in patients with left-sided CAS (RR, 1.29; 1.05–1.58), increased internal carotid artery–common carotid artery angulation (RR, 3.41; 1.52–7.63), and when the target internal carotid artery stenosis was > 10 mm (RR, 2.36; 1.28–3.38). There was no significant increase in risk of stroke or death in patients with type III aortic arch, aortic arch calcification, or with ostial involvement, calcification, ulceration or degree of stenosis of the target internal carotid artery stenosis. The use of a cerebral protection device was associated with a lower risk of stroke or death (RR, 0.55; 0.41–0.73). Risk was not related to stent or cerebral protection device type.

The investigators concluded that these results strongly suggest that some technical and anatomic factors, especially extreme angulation of the carotid artery, have an impact on the risks of CAS.