A Study Comparing Carotid Revascularization Endarterectomy Versus Stenting


About this study

The purpose of this study is to compare the relatively new procedure of stent-assisted carotid angioplasty to the traditional and accepted surgical approach of carotid endarterectomy for the treatment of carotid artery stenosis to prevent recurrent strokes in those patients who have had a TIA (transient ischemic attack) or a mild stroke within the past 6 months (symptomatic) and in those patients who have not had any symptoms within the past 6 months (asymptomatic).

Participation eligibility

Participant eligibility includes age, gender, type and stage of disease, and previous treatments or health concerns. Guidelines differ from study to study, and identify who can or cannot participate. There is no guarantee that every individual who qualifies and wants to participate in a trial will be enrolled. Contact the study team to discuss study eligibility and potential participation.

Inclusion Criteria

  • Symptomatic with recent neurological events (TIA or non-disabling stroke) and an associated carotid stenosis  ≥ 50% by angiography or ≥ 70% by ultrasound or ≥70% by Computed Tomography Angiography or Magnetic Resonance Angiography 
  • Asymptomatic with no recent (in the last 6 months) neurological events referable to the study with artery and carotid stenosis (patients with symptoms beyond 180 days are considered asymptomatic) ≥ 60% by angiography or ≥ 70% by ultrasound or ≥ 80% by CTA or MRA

Exclusion Criteria

  • Conditions that
    • Interfere with the evaluation of endpoints
    • Are known to interfere with the completion of CEA or CAS
    • Affect the likelihood of survival for the 4 year study period
  • Chronic atrial fibrillation and/or anti-coagulation or episodic atrial fibrillation within the last 6 months

Participating Mayo Clinic locations

Study statuses change often. Please contact the study team for the most up-to-date information regarding possible participation.

Mayo Clinic Location Status

Jacksonville, Fla.

Mayo Clinic principal investigator

Albert Hakaim, M.D.

Closed for enrollment

More information


  • 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. Read More on PubMed
  • Carotid endarterectomy (CEA) and medical therapy were shown superior to medical therapy alone for symptomatic (> or =50%) and asymptomatic (> or =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. Read More on PubMed
  • The Carotid Revascularization Endarterectomy vs. Stenting Trial (CREST) completed randomization on July 18, 2008. Sponsored by the National Institute of Neurological Disorders and Stroke (NINDS), the trial has enrolled 2,522 participants across North America and is the largest randomized clinical trial (RCT) comparing the efficacy of carotid artery stenting (CAS) to carotid endarterectomy (CEA). It is also the largest RCT to assess carotid revascularization in both symptomatic and asymptomatic patients with carotid artery stenosis. Conventional-risk patients with symptomatic carotid stenosis (> or =50% by angiography, > or =70% by ultrasound) or asymptomatic carotid stenosis (> or =60% by angiography, > or =70% by ultrasound) were randomized to both treatment arms in a 1:1 ratio. Eligibility criteria for CREST were similar to those of the previous NINDS-sponsored CEA RCTs. The investigational devices used in the CAS arm of the study are the RX Acculink stent and the RX Accunet embolic protection system, (Abbott Vascular, Santa Clara, Calif). The primary aim is to contrast the efficacy of CAS versus CEA in preventing stroke, myocardial infarction, and all-cause mortality during a 30-day peri-procedural period, and ipsilateral stroke over the follow-up period (extending up to four years). The secondary aims are to contrast the efficacy of CAS and CEA in men and women, the restenosis rates of the two procedures, health-related quality of life, and cost effectiveness of CAS and CEA. The conclusion of enrollment in CREST marks the end of a long recruitment period from 117 community and academic hospital centers across the United States and Canada. Each surgeon and interventionalist underwent a rigorous credentialing process that included performance-assessment of prior CEA and CAS procedures. Credentialing of interventionalists also included a review of additional CAS procedures enrolled into a CREST lead-in phase prior to entering patients into the randomized trial; 1564 patients were enrolled in the lead-in, the final pathway for the largest credentialing effort to date for any clinical trial. CREST will provide long-term follow-up after carotid revascularization based on systematic ultrasonographic and neurologic surveillance, and on quality of life and cost-effectiveness comparisons between CAS and CEA in the setting of a RCT. We present a brief description of the CREST protocol, impediments that were overcome during the trial, salient results from the lead-in phase of the trial, a summary of enrollment activities and characteristics of the final cohort, and a timeline for anticipated results from the randomized phase. Read More on PubMed
  • 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). Read More on PubMed
  • A heightened risk of stroke and death among octogenarians undergoing carotid artery stenting (CAS) has been reported. The multicenter Carotid Revascularization Endarterectomy vs. Stent Trial (CREST) supported by the National Institute of Neurological Disorders, National Institutes of Health, compares the efficacy of carotid endarterectomy (CEA) and CAS in an ongoing clinical trial. This effort also includes a "lead-in" phase of symptomatic (>50% stenosis) and asymptomatic (>70% stenosis) patients. The protocol calls for patients to receive aspirin and clopidogrel before and 30-days after CAS and to be examined by a study neurologist preprocedure, at 24-hours, and at 30-day. The occurrence of stroke and death was reviewed by an independent clinical events committee. Read More on PubMed
  • 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). Read More on PubMed
  • The Carotid Revascularization Endarterectomy versus Stenting Trial (CREST) is a prospective, randomized, multicenter clinical trial of carotid endarterectomy (CEA) versus carotid artery stenting (CAS) as prevention for stroke in patients with symptomatic stenosis greater than or equal to 50%. CREST is sponsored by the US National Institute of Neurological Disorders and Stroke (NINDS) of the US National Institutes of Health (NIH), with additional support by a device manufacturer, and will provide data to the US Food and Drug Administration (FDA) for evaluation of a stent device. Because of budget constraints for CREST, Health Care Financing Administration (HCFA) reimbursement for hospital costs incurred by CREST patients will be essential. The involvement of academic scientists, industry, and three separate government agencies (NIH, FDA, HCFA) has presented many challenges in conducting the trial. A review of the pathways followed to meet these challenges may be helpful to others seeking to facilitate sharing of the costs and burdens of conducting innovative clinical research. Read More on PubMed

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