Background: Optimum management of carotid stenosis, both symptomatic (sx) and asymptomatic (asx), remains controversial despite clinical trials evaluating Carotid Endarterectomy (CEA) and Carotid Stenting (CAS). Objective: We compared attitudes in management of carotid stenosis between experts in Europe (EU), and North America (NA). Methods: From April 2011 to July 2012, a 3-round, email-Delphi survey was sent to members of the European Stroke Organisation (n=390) and to a list of NA stroke neurologists developed at the University of Texas at Houston Stroke Program (n=289). Those completing the survey were shown all responses broken down by EU/NA after each of the first 2 survey rounds. Continent specific consensus was defined a priori to be > 80% agreement. Results: 100 (15%, of which 73% EU) participated in all 3-Delphi rounds, 19% of all EU vs 9% NA (χ2=11.62, p=0.0007): 76% male; 69% treating between 1-8 new cases of carotid stenosis per month. In the final round, EU reached consensus in 7/11 statements (3 reached in phase-I), while NA did in 4/11 (1 reached in phase-I).Ninety-percent of EU vs 70% of NA (χ2=8.09, p=0.017) disagreed that CAS and CEA are equivalent treatments for sx carotid stenosis, and stated that CEA is superior. There remains a significant difference between EU and NA when considering ipsilateral stroke and death < 30 days as primary outcome (χ2=12.18, p=0.007). Sixty-nine-percent of NA agreed that there is a stronger indication for CAS over CEA in patients < 65 years for sx carotid stenosis whereas 55% of EU (χ2=11.39, p=0.023) disagreed with the statement. When asked how likely they would recommend CEA for an asx carotid stenosis, 81% of EU and 80% of NA said ‘sometimes’. When asked how likely they would recommend CAS for an asx carotid stenosis, 62% of NA said ‘sometimes’ vs 60% of EU said ‘never’(χ2=3.54, p=0.06). Conclusion: There are several clear differences in attitudes regarding the management of carotid stenosis between EU and NA: EU has a stronger attitude towards superiority of CEA while in NA there is more equipoise between the two treatments. Areas of lack of consensus may provide direction for future clinical trials.
Abstract 84: Low Risk of Stroke or Death Among Patients With Recently Symptomatic Carotid Stenosis Awaiting Revascularisation - A Pooled Analysis of Randomised Trials
Background: Historical data suggest that patients with recently symptomatic carotid stenosis are at high risk of early recurrent stroke. Guidelines therefore recommend revascularization within 2 weeks of symptoms. We assessed the risk of stroke or death occurring before revascularization in modern trials of symptomatic carotid stenosis. Methods: We pooled data of all individual patients with symptomatic carotid stenosis randomised to stenting (CAS) or endarterectomy (CEA) in the EVA-3S, SPACE, ICSS and CREST trials. The outcome event (OE) was death or any stroke occurring between randomization and treatment by CAS or CEA, or up to 120 days after randomization among patients not undergoing treatment in this period. Results: 4707 patients were included in the analysis. Median time from qualifying event until randomization was 18 (interquartile range 7-50) days. Median time from randomization until treatment was 6 (2-11) days in the CAS group, and 7 (3-12) days in the CEA group (p<0.001). 31% of patients in the CAS group and 27% in the CEA group underwent revascularization within 14 days of the qualifying event. The OE occurred in 21 patients (CAS: 8, CEA: 13), all within 31 days of randomization (Kaplan Meier estimate: 2.4%, standard error 0.7%; fig.), including 18 non-fatal strokes, 1 fatal stroke, and 2 non-stroke related deaths. In 2 of the patients, the date of the qualifying event was unknown, in 8 patients the OE occurred within 14 days of the qualifying event and in 11 patients >14 days after the qualifying event. All patients with the OE had severe (70-99% degree) stenosis. No other baseline variables predicted the OE. Discussion: Despite the fact that less than a third of patients underwent revascularization within 14 days of the qualifying event, only 2.4% of patients had a recurrent stroke or died before treatment. The risk is lower than expected from historical data, which may reflect advances in medical therapy. Patients at risk are those with severe degree of stenosis.
Absence of Consistent Sex Differences in Outcomes From Symptomatic Carotid Endarterectomy and Stenting Randomized Trials
Background and Purpose: CREST (Carotid Revascularization Endarterectomy Versus Stenting Trial) reported a higher periprocedural risk for any stroke, death, or myocardial infarction for women randomized to carotid artery stenting (CAS) compared with women randomized to carotid endarterectomy (CEA). No difference in risk by treatment was detected for women relative to men in the 4-year primary outcome. We aimed to conduct a pooled analysis among symptomatic patients in large randomized trials to provide more precise estimates of sex differences in the CAS-to-CEA risk for any stroke or death during the 120-day periprocedural period and ipsilateral stroke thereafter. Methods: Data from the Carotid Stenosis Trialists’ Collaboration included outcomes from symptomatic patients in EVA-3S (Endarterectomy Versus Angioplasty in Patients With Symptomatic Severe Carotid Stenosis), SPACE (Stent-Protected Angioplasty Versus Carotid Endarterectomy in Symptomatic Patients), ICSS (International Carotid Stenting Study), and CREST. The primary outcome was any stroke or death within 120 days after randomization and ipsilateral stroke thereafter. Event rates and relative risks were estimated using Poisson regression; effect modification by sex was assessed with a sex-by-treatment-by-trial interaction term, with significant interaction defined a priori as P ≤0.10. Results: Over a median 2.7 years of follow-up, 433 outcomes occurred in 3317 men and 1437 women. The CAS-to-CEA relative risk of the primary outcome was significantly lower for women compared with men in 1 trial, nominally lower in another, and nominally higher in the other two. The sex-by-treatment-by-trial interaction term was significant ( P =0.065), indicating heterogeneity among trials. Contributors to this heterogeneity are primarily differences in periprocedural period. When the trials are nevertheless pooled, there were no significant sex differences in risk in any follow-up period. Conclusions: There were significant differences between trials in the magnitude of sex differences in treatment effect (CAS-to-CEA relative risk), indicating pooling data from these trials to estimate sex differences might not be valid. Whether sex is acting as an effect modifier of the CAS-to-CEA treatment effect in symptomatic patients remains uncertain. Registration: URL: https://www.clinicaltrials.gov ; Unique identifier: NCT00190398 (EVA-3S) and NCT00004732 (CREST). URL: https://www.isrctn.com ; Unique identifier: ISRCTN57874028 (SPACE) and ISRCTN25337470 (ICSS).
Abstract 42: CAS versus CEA Treatment Differences in Long-Term Outcomes and Post-Procedural Durability: the Carotid Stenosis Trialist Collaboration (CSTC)
Introduction: A 3.4% (95% CI: 2.1% to 4.7%) higher peri-procedural stroke and death risk has been previously documented for those treated with carotid artery stenting (CAS) relative to those treated with carotid endarterectomy (CEA). However, the CAS versus CEA treatment differences in long-term outcomes and the post-procedure durability have not been described. Methods: Data from the 4 largest CAS-versus-CEA randomized trials for treatment of symptomatic carotid atherosclerosis (EVA-3S, SPACE, ICSS, and CREST) were pooled, and treatment differences assessed for the outcome of any stroke or death during a 120-day peri-procedural period, plus ipsilateral stroke afterward. Results: Long-term follow-up was analysed for 4754 patients. Median length of follow-up across the studies ranged from 2.0 to 6.9 years, with 88 peri-procedural and 55 post-procedural events among those CEA-treated, and 169 and 64 for those CAS-treated. After the peri-procedural period, the annual rates of stroke following CAS was 0.6% (95% CI: 0.5 to 0.8) and following CEA 0.6% (95% CI: 0.5 to 0.8), resulting in non-significant durability differences of less than 1% over the period extending up to 9 years (see Table). The previously-documented 3.4% higher peri-procedural event rate in the CAS group contributed to a significant 3.1% (95% CI: 1.6% to 4.7%) treatment difference at 1-year, and the aforementioned similar durability implied that this significant difference remained relatively constant over the period extending up to 9 years (see table). Conclusions: The post-procedure durability of CAS and CEA were similar, both with event rates below 1%. The similarity of post-procedure events rates implies that the previously-documented higher peri-procedural in the CAS group is “carried forward” with a higher risk of outcomes extending to 9-years.
Safety of Carotid Revascularization in Patients With a History of Coronary Heart Disease
Background and Purpose— We investigated whether procedural stroke or death risk of carotid artery stenting (CAS) compared with carotid endarterectomy (CEA) is different in patients with and without history of coronary heart disease (CHD) and whether the treatment-specific impact of age differs. Methods— We combined individual patient data of 4754 patients with symptomatic carotid stenosis from 4 randomized trials (EVA-3S [Endarterectomy Versus Angioplasty in Patients With Symptomatic Severe Carotid Stenosis], SPACE [Stent-Protected Angioplasty Versus Carotid Endarterectomy], ICSS [International Carotid Stenting Study], and CREST [Carotid Revascularization Endarterectomy Versus Stenting Trial]). Procedural risk was defined as any stroke or death ≤30 days after treatment. We compared procedural risk between both treatments with Cox regression analysis, stratified by history of CHD and age (<70, 70–74, ≥75 years). History of CHD included myocardial infarction, angina, or coronary revascularization. Results— One thousand two hundred ninety-three (28%) patients had history of CHD. Procedural stroke or death risk was higher in patients with history of CHD. Procedural risk in patients treated with CAS compared with CEA was consistent in patients with history of CHD (8.3% versus 4.6%; hazard ratio [HR], 1.96; 95% CI, 0.67–5.73) and in those without (6.9% versus 3.6%; HR, 1.93; 95% CI, 1.40–2.65; P interaction =0.89). In patients with history of CHD, procedural risk was significantly higher after CAS compared with CEA in patients aged ≥75 (CAS-to-CEA HR, 2.78; 95% CI, 1.32–5.85), but not in patients aged <70 (HR, 1.71; 95% CI, 0.79–3.71) and 70 to 74 years (HR, 1.09; 95% CI, 0.45–2.65). In contrast, in patients without history of CHD, procedural risk after CAS was higher in patients aged 70 to 74 (HR, 3.62; 95% CI, 1.80–7.29) and ≥75 years (HR, 2.64; 95% CI, 1.52–4.59), but equal in patients aged <70 years (HR, 1.05; 95% CI, 0.63–1.73; 3-way P interaction =0.09). Conclusions— History of CHD does not modify procedural stroke or death risk of CAS compared with CEA. CAS might be as safe as CEA in patients with history of CHD aged <75 years, whereas for patients without history of CHD, risk after CAS compared with CEA was only equal in those aged <70 years.
Immediate and Delayed Procedural Stroke or Death in Stenting Versus Endarterectomy for Symptomatic Carotid Stenosis
Background and Purpose— Stenting for symptomatic carotid stenosis (carotid artery stenting [CAS]) carries a higher risk of procedural stroke or death than carotid endarterectomy (CEA). It is unclear whether this extra risk is present both on the day of procedure and within 1 to 30 days thereafter and whether clinical risk factors differ between these periods. Methods— We analyzed the risk of stroke or death occurring on the day of procedure (immediate procedural events) and within 1 to 30 days thereafter (delayed procedural events) in 4597 individual patients with symptomatic carotid stenosis who underwent CAS (n=2326) or CEA (n=2271) in 4 randomized trials. Results— Compared with CEA, patients treated with CAS were at greater risk for immediate procedural events (110 versus 42; 4.7% versus 1.9%; odds ratio, 2.6; 95% CI, 1.9–3.8) but not for delayed procedural events (59 versus 46; 2.5% versus 2.0%; odds ratio, 1.3; 95% CI, 0.9–1.9; interaction P =0.006). In patients treated with CAS, age increased the risk for both immediate and delayed events while qualifying event severity only increased the risk of delayed events. In patients treated with CEA, we found no risk factors for immediate events while a higher level of disability at baseline and known history of hypertension were associated with delayed procedural events. Conclusions— The increased procedural stroke or death risk associated with CAS compared with CEA was caused by an excess of events occurring on the day of procedure. This finding demonstrates the need to enhance the procedural safety of CAS by technical improvements of the procedure and increased operator skill. Higher age increased the risk for both immediate and delayed procedural events in CAS, mechanisms of which remain to be elucidated. Clinical Trial Registration— URL: https://clinicaltrials.gov . Unique identifier: NCT00190398. URL: http://www.isrctn.com . Unique identifier: ISRCTN57874028. URL: http://www.isrctn.com . Unique identifier: ISRCTN25337470. URL: https://clinicaltrials.gov . Unique identifier: NCT00004732.
Prediction Models for Clinical Outcome After a Carotid Revascularization Procedure
Background and Purpose— Prediction models may help physicians to stratify patients with high and low risk for periprocedural complications or long-term stroke risk after carotid artery stenting or carotid endarterectomy. We aimed to evaluate external performance of previously published prediction models for short- and long-term outcome after carotid revascularization in patients with symptomatic carotid artery stenosis. Methods— From a literature review, we selected all prediction models that used only readily available patient characteristics known before procedure initiation. Follow-up data from 2184 carotid artery stenting and 2261 carotid endarterectomy patients from 4 randomized trials (EVA-3S [Endarterectomy Versus Angioplasty in Patients With Symptomatic Severe Carotid Stenosis], SPACE [Stent-Protected Angioplasty Versus Carotid Endarterectomy], ICSS [International Carotid Stenting Study], and CREST [Carotid Revascularization Endarterectomy Versus Stenting Trial]) were used to validate 23 short-term outcome models to estimate stroke or death risk ≤30 days after the procedure and the original outcome measure for which the model was developed. Additionally, we validated 7 long-term outcome models for the original outcome measure. Predictive performance of the models was assessed with C statistics and calibration plots. Results— Stroke or death ≤30 days after the procedure occurred in 158 (7.2%) patients after carotid artery stenting and in 84 (3.7%) patients after carotid endarterectomy. Most models for short-term outcome after carotid artery stenting (n=4) or carotid endarterectomy (n=19) had poor discriminative performance (C statistics ranging from 0.49–0.64) and poor calibration with small absolute risk differences between the lowest and highest risk groups and overestimation of risk in the highest risk groups. Long-term outcome models (n=7) had a slightly better performance with C statistics ranging from 0.59 to 0.67 and reasonable calibration. Conclusions— Current models did not reliably predict outcome after carotid revascularization in a trial population of patients with symptomatic carotid stenosis. In particular, prediction of short-term outcome seemed to be difficult. Further external validation of existing prediction models or development of new prediction models is needed before such models can be used to support treatment decisions in individual patients.
Transatlantic Differences in Management of Carotid Stenosis: BRIDGing the Gap in StrokE Management (BRIDGE) Project
Background and Purpose: Management of carotid stenosis remains controversial despite several trials evaluating carotid endarterectomy (CEA) and carotid angioplasty/stenting (CAS). We compared attitudes in the management of carotid stenosis between selected experts within Europe and North America. Methods: A 3-phase Delphi survey was e-mailed to select stroke experts from Europe (n = 390) and North America (n = 289). Those completing the initial survey were shown all responses after each survey round. Consensus was defined as ≥80% agreement. Results: For phases 1, 2, and 3, response rates were 32%, 62%, and 73%, respectively. Overall, 100 (15%) of 679 participated in all 3 phases, 19% Europeans versus 9% North Americans ( P = .0007). The European group reached consensus in 6 of 15 statements; The North American group reached consensus in 4 of 15. Ninety percentage of Europeans versus 70% of North Americans ( P = .017) stated CEA is superior to CAS for symptomatic carotid stenosis. This difference was not significant in the final model (adjusted odds ratio: 3.72 [95% confidence interval: 0.95-14.5]). Sixty-nine percentage of North Americans agreed there is a stronger indication for CAS over CEA in patients younger than 65 years for symptomatic carotid stenosis, whereas 55% of Europeans ( P = .023) disagreed. For asymptomatic carotid stenosis, when asked how likely they would recommend CAS, 62% North Americans said “sometimes” versus 60% of Europeans said “never” ( P = .06). Conclusion: The majority of North American and European respondents did not consider the 2 procedures equivalent and seemed to indicate that CEA was preferred for the management of carotid stenosis. These findings need to be further explored to help establish evidence-based guidelines.