Stenting for symptomatic carotid stenosis in patients 70 years and older should be avoided, but the procedure might be as safe as endarterectomy in younger patients, according to results of a prospectively defined meta-analysis published Online First September 10 in The Lancet.
“Results from randomised controlled trials have shown a higher short-term risk of stroke associated with carotid stenting than with carotid endarterectomy for the treatment of symptomatic carotid stenosis,” write Martin M. Brown, MD, National Hospital for Neurology and Neurosurgery and University College London, London, United Kingdom, and colleagues from the Carotid Stenting Trialists’ Collaboration. “However, these trials were underpowered for investigation of whether carotid artery stenting might be a safe alternative to endarterectomy in specific patient subgroups.”
The investigators conducted a preplanned meta-analysis of individual patient data from 3 randomized controlled trials: the Endarterectomy versus Angioplasty in Patients with Symptomatic Severe Carotid Stenosis (EVA-3S) trial, the Stent-Protected Angioplasty versus Carotid Endarterectomy (SPACE) trial, and the International Carotid Stenting Study (ICSS).
The data from the trials, comprising 3433 patients, were pooled and analyzed, with any stroke or death as the primary outcome.
In the first 120 days after randomization, any stroke or death was 53% more likely to occur in the carotid stenting group vs the carotid endarterectomy group, occurring in 8.9% (153/1725 patients) randomly assigned to stenting vs 5.8% (99/1708 patients) randomly assigned to carotid endarterectomy (risk ratio [RR], 1.53; 95% confidence interval [CI], 1.20 – 1.95; P = .0006.)
Of all subgroup variables assessed in the meta-analysis, only age significantly modified the treatment effect. In patients younger than 70 years, the estimated 120-day risk for stroke or death was 5.8% in the carotid stenting group and 5.7% in the carotid endarterectomy group (RR, 1.00; 95% CI, 0.68 – 1.47).
However, in patients 70 years or older, the estimated risk for stroke or death was twice that with carotid endarterectomy: 12.0% vs 5.9% (RR, 2.04; 95% CI, 1.48 – 2.82).
The study also found risk estimates for stroke or death within the first 30 days of treatment to be similar in patients 70 years and younger for both groups (5.1% for stenting vs 4.5% for carotid endarterectomy). However, for patients older than 70 years, the estimates were 10.5% in the stenting group vs 4.4% in the endarterectomy group (RR, 2.41; 95% CI, 1.65 – 3.51).
The findings suggest that stenting might be a viable alternative to endarterectomy in younger patients, although there is some uncertainty about the potentially higher rate of recurrent stenosis after stenting vs endarterectomy and the implications this might have for future stroke risk in these patients, the study authors comment.
“With these caveats in mind, an approach of offering stenting when technically feasible as an alternative option to endarterectomy to patients younger than 65-70 years with symptomatic carotid stenosis, in centres in which acceptable periprocedural outcomes have been independently verified, might seem justified, as long as patients are made aware of a possible increase in the risk of restenosis,” they write.
Limitations of the meta-analysis include insufficient statistical power to compare treatment risks in some subgroups, such as women; patients presenting with ocular ischemia; and patients with severe contralateral carotid disease. Also, the number of procedures undertaken by each surgeon and interventionalist before they joined the trials is unknown, as is the effect of individual experience on complication rates.
The study authors conclude that the prospectively defined meta-analysis of EVA-3S, SPACE, and ICSS that showed a highly significant, age-dependent variation of risks from stenting has implications for clinical practice. “There is strong evidence that, in the short term, the harm of stenting compared with endarterectomy decreases with younger age,” they write.
The study was funded by The Stroke Association. The study authors have disclosed no relevant financial relationships.
Lancet. Published online September 10, 2010.