NEW YORK (Reuters Health) – A long-term trial has shown “no evidence to support the use of endovascular treatment” for carotid artery stenosis over endarterectomy in patients who are willing and able to undergo surgery, according to a paper published online August 29 in The Lancet Neurology.

Between 1992 and 1971, 504 participants in the Carotid and Vertebral Artery Transluminal Angioplasty Study (CAVATAS) who were suitable for either treatment were randomized to undergo either angioplasty, with or without stenting, or surgery, and then were followed for up to 11 years. Initial results, published in 2001, showed that rates of the primary outcome – stroke lasting more than 7 days or death – were similar with both treatments.

The current analysis, reported by Dr. Martin M. Brown at the National Hospital for Neurology and Neurosurgery in London and colleagues, found that the endovascular group had a higher rate of minor strokes lasting less than 7 days within the first month after treatment (8 vs 1), but there were more cranial nerve palsies (22 vs 0) in the surgery group.

Over the entire course of follow-up, both groups had the same number of other strokes or death (25 vs 25). The 8-year incidence for any non-perioperative stroke was 21.1% for endovascular treatment versus 15.4% for endarterectomy. None of the differences in outcomes was statistically significant.

Subgroup analysis suggested that patients over 67 and those with ischemic heart disease might have a lower long-term risk of stroke after treatment with endarterectomy.

These findings only “support the use of endovascular treatment … in patients in whom carotid endarterectomy is contraindicated or who prefer to risk the possibly greater hazard of endovascular treatment over surgery.”

In a separate paper, Dr. Brown and his associates compare restenosis rates in a subset of the CAVATAS cohort: 200 patients in the endovascular group and 213 in the endarterectomy group.

On ultrasonography at a median of 4 years and clinical follow-up at a median of 5 years after treatment, severe restenosis (70% or greater) occurred significantly more often after angioplasty (31%, vs 11% in the endarterectomy arm, adjusted hazard ratio 3.17, p < 0.001). The increased incidence of severe restenosis was linked in turn with a small increased risk of ipsilateral strokes (roughly 2% per year).

The 50 patients who received stents, however, had a lower risk of severe restenosis than those who had angioplasty alone (HR 0.43, p = 0.04).

Risk factors for severe carotid restenosis, regardless of treatment received, were current or past smoking (HR 2.32, p = 0.01) and moderate (50%-69%) residual or early recurrent stenosis within 2 months of treatment (HR 3.76, p = 0.002).

The authors do not recommend elective carotid reinterventional treatment for asymptomatic carotid restenosis, even if severe, given the low risk of ipsilateral stroke.

In a related commentary, Dr. Peter M. Rothwell from John Radcliffe Hospital in Oxford, UK, points out that even with “minor strokes” that resolve quickly, “risks of cognitive decline, fatigue, depression, and epilepsy do not.”

Given what we know now, he adds, “the routine use of stenting in patients with recent symptoms of carotid stenosis who are suitable for endarterectomy can no longer be justified.”

He concludes: “Most patients who have undergone stenting for symptomatic carotid stenosis outside of randomized controlled trials …have faced a greater procedural risk of stroke, a greater risk of severe restenosis, and a worse-long-term outcome than if they had had endarterectomy.”

Reference:
Lancet Neurol 2009.