IMPORTANCE: Carotid endarterectomy and carotid artery stenting are the leading approaches to revascularization for carotid stenosis, yet contemporary data on trends in rates and outcomes are limited. ...OBJECTIVE: To describe US national trends in performance and outcomes of carotid endarterectomy and stenting among Medicare beneficiaries from 1999 to 2014. DESIGN, SETTING, AND PARTICIPANTS: Serial cross-sectional analysis of Medicare fee-for-service beneficiaries aged 65 years or older from 1999 to 2014 using the Medicare Inpatient and Denominator files. Spatial mixed models adjusted for age, sex, and race were fit to calculate county-specific risk-standardized revascularization rates. Mixed models were fit to assess trends in outcomes after adjustment for demographics, comorbidities, and symptomatic status. EXPOSURES: Carotid endarterectomy and carotid artery stenting. MAIN OUTCOMES AND MEASURES: Revascularization rates per 100 000 beneficiary-years of fee-for-service enrollment, in-hospital mortality, 30-day stroke or death, 30-day stroke, myocardial infarction, or death, 30-day all-cause mortality, and 1-year stroke. RESULTS: During the study, 937 111 unique patients underwent carotid endarterectomy (mean age, 75.8 years; 43% women) and 231 077 underwent carotid artery stenting (mean age, 75.4 years; 49% women). There were 81 306 patients who underwent endarterectomy in 1999 and 36 325 in 2014; national rates per 100 000 beneficiary-years decreased from 298 in 1999-2000 to 128 in 2013-2014 (P < .001). The number of patients who underwent stenting ranged from 10 416 in 1999 to 22 865 in 2006 (an increase per 100 000 beneficiary-years from 40 in 1999-2000 to 75 in 2005-2006; P < .001); by 2014, there were 10 208 patients who underwent stenting and the rate decreased to 38 per 100 000 beneficiary-years (P < .001). Outcomes improved over time despite increases in vascular risk factors (eg, hypertension prevalence increased from 67% to 81% among patients who underwent endarterectomy and from 61% to 70% among patients who underwent stenting) and the proportion of symptomatic patients (all P < .001). There were adjusted annual decreases in 30-day ischemic stroke or death of 2.90% (95% CI, 2.63% to 3.18%) among patients who underwent endarterectomy and 1.13% (95% CI, 0.71% to 1.54%) among patients who underwent stenting; an absolute decrease from 1999 to 2014 was observed for endarterectomy (1.4%; 95% CI, 1.2% to 1.5%) but not stenting (−0.1%; 95% CI, −0.5% to 0.4%). Rates for 1-year ischemic stroke decreased after endarterectomy (absolute decrease, 3.5% 95% CI, 3.2% to 3.7%; adjusted annual decrease, 2.17% 95% CI, 2.00% to 2.34%) and stenting (absolute decrease, 1.6% 95% CI, 1.2% to 2.1%; adjusted annual decrease, 1.86% 95% CI, 1.45%-2.26%). Additional improvements were noted for in-hospital mortality, 30-day stroke, myocardial infarction, or death, and 30-day all-cause mortality as well as within demographic subgroups. CONCLUSIONS AND RELEVANCE: Among fee-for-service Medicare beneficiaries, the performance of carotid endarterectomy declined from 1999 to 2014, whereas the performance of carotid artery stenting increased until 2006 and then declined from 2007 to 2014. Outcomes improved despite increases in vascular risk factors.
Summary Background In the randomised Carotid Revascularization Endarterectomy versus Stenting Trial (CREST), the primary endpoint did not differ between carotid artery stenting and carotid ...endarterectomy in patients with symptomatic and asymptomatic stenosis. A prespecified secondary aim was to examine differences by sex. Methods Patients who were asymptomatic or had had a stroke or transient ischaemic attack within 180 days before random allocation were enrolled in CREST at 117 clinical centres in the USA and Canada. The primary outcome was the composite of stroke, myocardial infarction, or death during the periprocedural period or ipsilateral stroke within 4 years. We used standard survival methods including Kaplan-Meier survival curves and sex-by-treatment interaction term to assess the relation between patient factors and risk of reaching the primary outcome. Analyses were by intention to treat. CREST is registered with ClinicalTrials.gov , NCT00004732. Findings Between Dec 21, 2000, and July 18, 2008, 2502 patients were randomly assigned to carotid endarterectomy (n=1240) or carotid artery stenting (n=1262), 872 (34·9%) of whom were women. Rates of the primary endpoint for carotid artery stenting compared with carotid endarterectomy were 6·2% versus 6·8% in men (hazard ratio HR 0·99, 95% CI 0·66–1·46) and 8·9% versus 6·7% in women (1·35, 0·82–2·23). There was no significant interaction in the primary endpoint between sexes (interaction p=0·34). Periprocedural events occurred in 35 (4·3%) of 807 men assigned to carotid artery stenting compared with 40 (4·9%) of 823 assigned to carotid endarterectomy (HR 0·90, 95% CI 0·57–1·41) and 31 (6·8%) of 455 women assigned to carotid artery stenting compared with 16 (3·8%) of 417 assigned to carotid endarterectomy (1·84, 1·01–3·37; interaction p=0·064). Interpretation Periprocedural risk of events seems to be higher in women who have carotid artery stenting than those who have carotid endarterectomy whereas there is little difference in men. Additional data are needed to confirm whether this differential risk should be taken into account in decisions for treatment of carotid disease in women. Funding National Institute of Neurological Disorders and Stroke and Abbott Vascular Solutions (formerly Guidant).
In this randomized comparison of stenting and endarterectomy as treatment for carotid-artery stenosis, there was no significant difference in the rate of the composite primary end point of stroke, ...myocardial infarction, or death (7.2% and 6.8%, respectively; P=0.51). Stroke was more common with carotid-artery stenting than carotid endarterectomy; myocardial infarction was more common with carotid endarterectomy. The 4-year rate of stroke or death was 6.4% for carotid-artery stenting and 4.7% for carotid endarterectomy (P=0.03).
In this randomized comparison of stenting and endarterectomy as treatment for carotid-artery stenosis, there was no significant difference in the rate of the composite primary end point of stroke, myocardial infarction, or death (7.2% and 6.8%, respectively).
Carotid-artery atherosclerosis is an important cause of ischemic stroke.
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Carotid endarterectomy has been established as effective treatment for both symptomatic patients and asymptomatic patients.
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Carotid-artery stenting is another option for treatment. The results of randomized trials comparing carotid-artery stenting and carotid endarterectomy for use in symptomatic patients are conflicting.
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The primary aim of the Carotid Revascularization Endarterectomy vs. Stenting Trial (CREST) was to compare the outcomes of carotid-artery stenting with those of carotid endarterectomy among patients with symptomatic or asymptomatic extracranial carotid stenosis.
Methods
Study Design
CREST is a randomized, controlled trial with blinded end-point adjudication. Ethics review . . .
High stroke event rates among carotid artery stenting (CAS)-treated patients in the Carotid Revascularization Endarterectomy Versus Stenting Trial (CREST) lead-in registry generated an a priori ...hypothesis that age may modify the relative efficacy of CAS versus carotid endarterectomy (CEA). In the primary CREST report, we previously noted significant effect modification by age. Here we extend this investigation by examining the relative efficacy of the components of the primary end point, the treatment-specific impact of age, and contributors to the increasing risk in CAS-treated patients at older ages.
Among 2502 CREST patients with high-grade carotid stenosis, proportional hazards models were used to examine the impact of age on the CAS-to-CEA relative efficacy, and the impact of age on risk within CAS-treated and CEA-treated patients.
Age acted as a treatment effect modifier for the primary end point (P interaction=0.02), with the efficacy of CAS and CEA approximately equal at age 70 years. For CAS, risk for the primary end point increased with age (P<0.0001) by 1.77-times (95% confidence interval, 1.38-2.28) per 10-year increment; however, there was no evidence of increased risk for CEA-treated patients (P=0.27). Stroke events were the primary contributor to the overall effect modification (P interaction=0.033), with equal risk at ≈64 years. The treatment-by-age interaction for CAS and CEA was not altered by symptomatic status (P=0.96) or by sex (P=0.45).
Outcomes after CAS versus CEA were related to patient age, attributable to increasing risk for stroke after CAS at older ages. Patient age should be an important consideration when choosing between the 2 procedures for treating carotid stenosis.
URL: http://www.clinicaltrials.gov. Unique identifier: NCT00004732.
We report patient enrollment and retention by race and ethnicity in the CREST (Carotid Revascularization Endarterectomy Versus Stent Trial) and assess potential effect modification by race/ethnicity. ...In addition, we discuss the challenge of detecting differences in study outcomes when subgroups are small and the event rate is low.
We compared 2502 patients by race, ethnicity, baseline characteristics, and primary outcome (any periprocedural stroke, death, or myocardial infarction and subsequent ipsilateral stroke up to 10 years).
Two hundred forty (9.7%) patients were minority by race (6.1%) or ethnicity (3.6%); 109 patients (4.4%) were black, 32 (1.3%) Asian, 2332 (93.4%) white, 11 (0.4%) other, and 18 (0.7%) unknown. Ninety (3.6%) were Hispanic, 2377 (95%) non-Hispanic, and 35 (1.4%) unknown. The rate of the primary end point for all patients was 10.9%±0.9% at 10 years and did not differ by race or ethnicity (
>0.24).
The proportion of minorities recruited to CREST was below their representation in the general population, and retention of minority patients was lower than for whites. Primary outcomes did not differ by race or ethnicity. However, in CREST (like other studies), the lack of evidence of a racial/ethnic difference in the treatment effect should be interpreted with caution because of low statistical power to detect such a difference.
URL: http://www.clinicaltrials.gov. Unique identifier: NCT00004732.
Credentialing of vascular surgeons to perform carotid artery stenting (CAS) continues to be a major issue confronting the specialty of Vascular Surgery. Cannulation of aortic arch branches, and ...placement of carotid antiembolic devices and stents constitute the major technical challenges to vascular surgeons becoming credentialed to perform CAS. The multicenter Carotid Revascularization Endarterectomy vs Stenting Trial (CREST), supported by the National Institute of Neurological Disorders and Stroke, National Institute of Health, reviews credentials of interventionalists, including surgeons, for the trial's “lead-in” phase of CAS to treat symptomatic (>50% stenosis) and asymptomatic (>70% stenosis).
Vascular surgeons requesting participation in CREST must have achieved basic interventional credentialing criteria as recommended by the Society of Vascular Surgery. Each interventionalist is asked to submit notes and narrative summaries from a series of 10 to 30 CAS procedures for review by a multi-specialty review committee before being approved to participate in CREST. Thereafter, during the lead-in phase of CREST, each approved interventionalist is asked to perform CAS procedures using the study devices in as many as 20 patients. In this interim report from the CREST lead-phase, the association of specialty of operator (vascular surgeon, neurosurgeon, other specialist) and periprocedural stroke and death rate was examined in patients undergoing CAS. In addition, current enrollment volume in the lead-in phase by specialty of the principal investigator was examined.
Thirty-two of 134 (23.9%) CREST-credentialed interventionalists are vascular surgeons (n = 22; 16.4%) or neurosurgeons (n = 10; 7.5%). For events monitored through March 31, 2004, 789 patients had undergone CAS procedures performed by these 134 specialists. Thirty-day stroke and death rate was 4.6%, and myocardial infarction was observed in 1.1% of patients. Serious adverse events have not been clustered at individual institutions, and no significant differences have been observed between vascular surgeons or neurosurgeons and other credentialed specialists.
Vascular surgeons with basic catheter and guide wire skills, particularly those who have incorporated diagnostic cerebral angiography into their practice, can be credentialed to perform CAS. Individuals or groups should devote a number of cases (n = 10-30 per surgeon) to CAS to accomplish this goal. Pending US Food and Drug Administration approval of devices and Center for Medicaid and Medicare Services reimbursement, institutional financial support for the performance of these procedures must be secured. The learning curve for CAS should not be considered so formidable as to discourage surgeons from adding these techniques of CAS to their procedural inventory.
Evidence indicates that center volume of cases affects outcomes for both carotid endarterectomy and stenting. We evaluated the effect of enrollment volume by site on complication rates in the Carotid ...Revascularization Endarterectomy Versus Stenting Trial (CREST).
The primary composite end point was any stroke, myocardial infarction, or death within 30 days or ipsilateral stroke in follow-up. The 477 approved surgeons performed >12 procedures per year with complication rates <3% for asymptomatic patients and <5% for symptomatic patients; 224 interventionists were certified after a rigorous 2 step credentialing process. CREST centers were divided into tertiles based on the number of patients enrolled into the study, with Group 1 sites enrolling <25 patients, Group 2 sites enrolling 25 to 51 patients, and Group 3 sites enrolling >51 patients. Differences in periprocedural event rates for the primary composite end point and its components were compared using logistic regression adjusting for age, sex, and symptomatic status within site-volume level.
The safety of carotid angioplasty and stenting and carotid endarterectomy did not vary by site-volume during the periprocedural period as indicated by occurrence of the primary end point (P=0.54) or by stroke and death (P=0.87). A trend toward an inverse relationship between center enrollment volume and complications was mitigated by adjustment for known risk factors.
Complication rates were low in CREST and were not associated with center enrollment volume. The data are consistent with the value of rigorous training and credentialing in trials evaluating endovascular devices and surgical procedures.
http://www.clinicaltrials.gov. Unique identifier: NCT00004732.
The success of carotid artery stenting in preventing stroke requires a low risk of periprocedural stroke and death. A comprehensive training and credentialing process was prerequisite to the ...randomized Carotid Revascularization Endarterectomy versus Stenting Trial (CREST) to assemble a competent team of interventionalists with low periprocedural event rates. Interventionalists submitted cases to a multidisciplinary Interventional Management Committee. This committee evaluated 427 applicants. Of these, 238 (56%) were selected to participate in the training program and the lead-in phase, 73 (17%) who had clinical registry experience and satisfactory results with the devices used in CREST were exempt from training and were approved for the randomized phase, and 116 (27%) did not qualify for training. At 30 days in the lead-in study, stroke, myocardial infarction, or death occurred in 6.1% of symptomatic subjects and 4.8% of asymptomatic subjects. Stroke or death occurred in 5.8% of symptomatic subjects and 3.8% of asymptomatic subjects. Outcomes were better for younger subjects and varied by operator training. Based on experience, training, and lead-in results, the Interventional Management Committee selected 224 interventionalists to participate in the randomized phase of CREST. We believe that the credentialing and training of interventionalists participating in CREST have been the most rigorous reported to date for any randomized trial evaluating endovascular treatments. The study identified competent operators, which ensured that the randomized trial results fairly contrasted outcomes between endarterectomy and stenting.
Rationale
Carotid endarterectomy (CEA) and medical therapy were shown superior to medical therapy alone for symptomatic (ge;50%) and asymptomatic (≥60%) stenosis. Carotid angioplasty stenting (CAS) ...offers a less invasive alternative. Establishing safety, efficacy, and durability of CAS requires rigorous comparison with CEA in symptomatic and asymptomatic patients.
Aims
The objective is to compare the efficacy of CAS versus CEA in patients with symptomatic (≥50%) or asymptomatic (≥60%) extracranial carotid stenosis.
Design
The Carotid Revascularization Endarterectomy vs. Stenting Trial (CREST) is a prospective, randomized, parallel, two-arm, multi-center trial with blinded endpoint adjudication. Primary endpoints are analyzed using standard time-to-event statistical modeling with adjustment for major baseline covariates. Primary analysis is on an intent-to-treat basis.
Study Outcomes
The primary outcome is the occurrence of any stroke, myocardial infarction, or death during a 30-day peri-procedural period, and ipsilateral stroke during follow-up of up to four years. Secondary outcomes include restenosis and health-related quality of life.
Several carotid endarterectomy randomized, controlled trials and series have reported higher perioperative stroke and death rates for women compared with men. The potential for this same relationship ...with carotid artery stenting was examined in the lead-in phase of the Carotid Revascularization Endarterectomy versus Stenting Trial (CREST).
CREST compares efficacy of carotid endarterectomy and carotid artery stenting in preventing stroke, myocardial infarction, and death in the periprocedural period and ipsilateral stroke over the follow-up period. CREST included a "lead-in" phase of symptomatic (>or=50% stenosis) and asymptomatic (>or=70% stenosis) patients. Patients were examined by a neurologist preprocedure, at 24 hours, and at 30 days. Review of stroke and death was by an independent events committee. The association of sex with periprocedural stroke and death was examined in 1564 patients undergoing carotid artery stenting (26.5% symptomatic).
Women comprised 37% of the lead-in cohort and did not differ from men by age, symptomatic status, or characteristics of the internal carotid artery. The 30-day stroke and death rate for women was 4.5% (26 of 579; 95% CI, 3.0% to 6.5%) compared with 4.2% (41 of 985; 95% CI, 3.0% to 5.6%) for men. The difference in stroke and death rate was not significant nor were there any significant differences by sex after adjustment for age, arterial characteristics, or cardiovascular risk factors.
These results do not provide evidence that women have a higher carotid artery stenting stroke and death rate compared with men. The potential differential periprocedural risk by sex will be prospectively addressed in the randomized phase of CREST.