Summary Background Stenting is an alternative to endarterectomy for treatment of carotid artery stenosis, but long-term efficacy is uncertain. We report long-term data from the randomised ...International Carotid Stenting Study comparison of these treatments. Methods Patients with symptomatic carotid stenosis were randomly assigned 1:1 to open treatment with stenting or endarterectomy at 50 centres worldwide. Randomisation was computer generated centrally and allocated by telephone call or fax. Major outcomes were assessed by an independent endpoint committee unaware of treatment assignment. The primary endpoint was fatal or disabling stroke in any territory after randomisation to the end of follow-up. Analysis was by intention to treat (ITT all patients) and per protocol from 31 days after treatment (all patients in whom assigned treatment was completed). Functional ability was rated with the modified Rankin scale. This study is registered, number ISRCTN25337470. Findings 1713 patients were assigned to stenting (n=855) or endarterectomy (n=858) and followed up for a median of 4·2 years (IQR 3·0–5·2, maximum 10·0). Three patients withdrew immediately and, therefore, the ITT population comprised 1710 patients. The number of fatal or disabling strokes (52 vs 49) and cumulative 5-year risk did not differ significantly between the stenting and endarterectomy groups (6·4% vs 6·5%; hazard ratio HR 1·06, 95% CI 0·72–1·57, p=0·77). Any stroke was more frequent in the stenting group than in the endarterectomy group (119 vs 72 events; ITT population, 5-year cumulative risk 15·2% vs 9·4%, HR 1·71, 95% CI 1·28–2·30, p<0·001; per-protocol population, 5-year cumulative risk 8·9% vs 5·8%, 1·53, 1·02–2·31, p=0·04), but were mainly non-disabling strokes. The distribution of modified Rankin scale scores at 1 year, 5 years, or final follow-up did not differ significantly between treatment groups. Interpretation Long-term functional outcome and risk of fatal or disabling stroke are similar for stenting and endarterectomy for symptomatic carotid stenosis. Funding Medical Research Council, Stroke Association, Sanofi-Synthélabo, European Union.
Abstract Background Brain lesions on diffusion-weighted imaging (DWI) are frequently found after carotid artery stenting (CAS), but their clinical relevance remains unclear. Objectives This study ...sought to investigate whether periprocedural ischemic DWI lesions after CAS or carotid endarterectomy (CEA) are associated with an increased risk of recurrent cerebrovascular events. Methods In the magnetic resonance imaging (MRI) substudy of ICSS (International Carotid Stenting Study), 231 patients with symptomatic carotid stenosis were randomized to undergo CAS (n = 124) or CEA (n = 107). MRIs were performed 1 to 7 days before and 1 to 3 days after treatment. The primary outcome event was stroke or transient ischemic attack in any territory occurring between the post-treatment MRI and the end of follow-up. Time to occurrence of the primary outcome event was compared between patients with (DWI+) and without (DWI–) new DWI lesions on the post-treatment scan in the CAS and CEA groups separately. Results Median time of follow-up was 4.1 years (interquartile range: 3.0 to 5.2). In the CAS group, recurrent stroke or transient ischemic attack occurred more often among DWI+ patients (12 of 62) than among DWI– patients (6 of 62), with a cumulative 5-year incidence of 22.8% (standard error SE: 7.1%) and 8.8% (SE: 3.8%), respectively (unadjusted hazard ratio: 2.85; 95% confidence interval: 1.05 to 7.72; p = 0.04). In DWI+ and DWI– patients, 8 and 2 events, respectively, occurred within 6 months after treatment. In the CEA group, there was no difference in recurrent cerebrovascular events between DWI+ and DWI– patients. Conclusions Ischemic brain lesions discovered on DWI after CAS seem to be a marker of increased risk for recurrent cerebrovascular events. Patients with periprocedural DWI lesions might benefit from more aggressive and prolonged antiplatelet therapy after CAS. (A Randomised Comparison of the Risks, Benefits and Cost Effectiveness of Primary Carotid Stenting With Carotid Endarterectomy: International Carotid Stenting Study; ISRCTN25337470 )
Summary Background In the Carotid and Vertebral Artery Transluminal Angioplasty Study (CAVATAS), early recurrent carotid stenosis was more common in patients assigned to endovascular treatment than ...it was in patients assigned to endarterectomy (CEA), raising concerns about the long-term effectiveness of endovascular treatment. We aimed to investigate the long-term risks of restenosis in patients included in CAVATAS. Methods 413 patients who were randomly assigned in CAVATAS and completed treatment for carotid stenosis (200 patients had endovascular treatment and 213 patients had endarterectomy) had prospective clinical follow-up at a median of 5 years and carotid duplex ultrasound at a median of 4 years. We investigated the cumulative long-term incidence of carotid restenosis after endovascular treatment and endarterectomy, the effect of the use of stents on restenosis after endovascular treatment, risk factors for the development of restenosis, and the effect of carotid restenosis on the risk of recurrent cerebrovascular events. Analysis was by intention to treat. This study is registered, number ISRCTN01425573. Findings Severe carotid restenosis (≥70%) or occlusion occurred significantly more often in patients in the endovascular arm than in patients in the endarterectomy arm (adjusted hazard ratio HR 3·17, 95% CI 1·89–5·32; p<0·0001). The estimated 5-year incidence of restenosis was 30·7% in the endovascular arm and 10·5% in the endarterectomy arm. Patients in the endovascular arm who were treated with a stent (n=50) had a significantly lower risk of developing restenosis of 70% or greater compared with those treated with balloon angioplasty alone (n=145; HR 0·43, 0·19–0·97; p=0·04). Current smoking or a history of smoking was a predictor of restenosis of 70% or more (2·32, 1·19–4·54; p=0·01) and the early finding of moderate stenosis (50–69%) up to 60 days after treatment was associated with the risk of progression to restenosis of 70% or more (3·76, 1·88–7·52; p=0·0002). The composite endpoint of ipsilateral non-perioperative stroke or transient ischaemic attack occurred more often in patients in whom restenosis of 70% or more was diagnosed in the first year after treatment compared with patients without restenosis of 70% or more (5-year incidence 23% vs 11%; HR 2·18, 1·04–4·54; p=0·04), but the increase in ipsilateral stroke alone was not significant (10% vs 5%; 1·67, 0·54–5·11). Interpretation Restenosis is about three times more common after endovascular treatment than after endarterectomy and is associated with recurrent ipsilateral cerebrovascular symptoms; however, the risk of recurrent ipsilateral stroke is low. Further data are required from on-going trials of stenting versus endarterectomy to ascertain whether long-term ultrasound follow-up is necessary after carotid revascularisation. Funding British Heart Foundation; UK National Health Service Management Executive; UK Stroke Association.
Summary Background Findings from randomised trials have shown a higher early risk of stroke after carotid artery stenting than after carotid endarterectomy. We assessed whether white-matter lesions ...affect the perioperative risk of stroke in patients treated with carotid artery stenting versus carotid endarterectomy. Methods Patients with symptomatic carotid artery stenosis included in the International Carotid Stenting Study (ICSS) were randomly allocated to receive carotid artery stenting or carotid endarterectomy. Copies of baseline brain imaging were analysed by two investigators, who were masked to treatment, for the severity of white-matter lesions using the age-related white-matter changes (ARWMC) score. Randomisation was done with a computer-generated sequence (1:1). Patients were divided into two groups using the median ARWMC. We analysed the risk of stroke within 30 days of revascularisation using a per-protocol analysis. ICSS is registered with controlled-trials.com , number ISRCTN 25337470. Findings 1036 patients (536 randomly allocated to carotid artery stenting, 500 to carotid endarterectomy) had baseline imaging available. Median ARWMC score was 7, and patients were dichotomised into those with a score of 7 or more and those with a score of less than 7. In patients treated with carotid artery stenting, those with an ARWMC score of 7 or more had an increased risk of stroke compared with those with a score of less than 7 (HR for any stroke 2·76, 95% CI 1·17–6·51; p=0·021; HR for non-disabling stroke 3·00, 1·10–8·36; p=0·031), but we did not see a similar association in patients treated with carotid endarterectomy (HR for any stroke 1·18, 0·40–3·55; p=0·76; HR for disabling or fatal stroke 1·41, 0·38–5·26; p=0·607). Carotid artery stenting was associated with a higher risk of stroke compared with carotid endarterectomy in patients with an ARWMC score of 7 or more (HR for any stroke 2·98, 1·29–6·93; p=0·011; HR for non-disabling stroke 6·34, 1·45–27·71; p=0·014), but there was no risk difference in patients with an ARWMC score of less than 7. Interpretation The presence of white-matter lesions on brain imaging should be taken into account when selecting patients for carotid revascularisation. Carotid artery stenting should be avoided in patients with more extensive white-matter lesions, but might be an acceptable alternative to carotid endarterectomy in patients with less extensive lesions. Funding Medical Research Council, the Stroke Association, Sanofi-Synthélabo, the European Union Research Framework Programme 5.
Summary Background Endovascular treatment (angioplasty with or without stenting) is an alternative to carotid endarterectomy for carotid artery stenosis but there are scarce long-term efficacy data ...showing that it prevents stroke. We therefore report the long-term results of the Carotid and Vertebral Artery Transluminal Angioplasty Study (CAVATAS). Methods Between March, 1992, and July, 1997, patients who presented at a participating centre with a confirmed stenosis of the internal carotid artery that was deemed equally suitable for either carotid endarterectomy or endovascular treatment were randomly assigned to either treatment in equal proportions by telephone or fax from the randomisation service at the Oxford Clinical Trials Unit, UK. Patients were seen by an independent neurologist at 1 and 6 months after treatment and then every year after randomisation for as long as possible, up to a maximum of 11 years. Major outcome events were transient ischaemic attack, non-disabling, disabling, and fatal stroke, myocardial infarction, and death from any other cause. Outcomes were adjudicated on by investigators who were masked to treatment. Analysis was by intention to treat. This study is registered, number ISRCTN 01425573. Findings 504 patients with stenosis of the carotid artery (90% symptomatic) were randomly assigned to endovascular treatment (n=251) or surgery (n=253). Within 30 days of treatment, there were more minor strokes that lasted less than 7 days in the endovascular group (8 vs 1) but the number of other strokes in any territory or death was the same (25 vs 25). There were more cranial nerve palsies (22 vs 0) in the endarterectomy group than in the endovascular group. Median length of follow up in both groups was 5 years (IQR 2–6). By comparing endovascular treatment with endarterectomy after the 30-day post-treatment period, the 8-year incidence and hazard ratio (HR) at the end of follow-up for ipsilateral non-perioperative stroke was 11·3% versus 8·6% (HR 1·22, 95% CI 0·59–2·54); for ipsilateral non-perioperative stroke or TIA was 19·3% versus 17·2% (1·29, 0·78–2·14); and for any non-perioperative stroke was 21·1% versus 15·4% (1·66, 0·99–2·80). Interpretation More patients had stroke during follow-up in the endovascular group than in the surgical group, but the rate of ipsilateral non-perioperative stroke was low in both groups and none of the differences in the stroke outcome measures was significant. However, the study was underpowered and the confidence intervals were wide. More long-term data are needed from the on going stenting versus endarterectomy trials. Funding British Heart Foundation; UK National Health Service Management Executive; UK Stroke Association.