2011 ASA/ACCF/AHA/AANN/AANS/ACR/ASNR/CNS/SAIP/SCAI/SIR/SNIS/SVM/SVS Guideline on the Management of Patients With Extracranial Carotid and Vertebral Artery Disease

HomeStrokeVol. 42, No. 82011 ASA/ACCF/AHA/AANN/AANS/ACR/ASNR/CNS/SAIP/SCAI/SIR/SNIS/SVM/SVS Guideline on the Management of Patients With Extracranial Carotid and Vertebral Artery Disease Free AccessResearch ArticlePDF/EPUBAboutView PDFView EPUBSections ToolsAdd to favoritesDownload citationsTrack citationsPermissions ShareShare onFacebookTwitterLinked InMendeleyReddit Jump toFree AccessResearch ArticlePDF/EPUB2011 ASA/ACCF/AHA/AANN/AANS/ACR/ASNR/CNS/SAIP/SCAI/SIR/SNIS/SVM/SVS Guideline on the Management of Patients With Extracranial Carotid and Vertebral Artery DiseaseA Report of the American College of Cardiology Foundation/American Heart Association Task Force on Practice Guidelines, and the American Stroke Association, American Association of Neuroscience Nurses, American Association of Neurological Surgeons, American College of Radiology, American Society of Neuroradiology, Congress of Neurological Surgeons, Society of Atherosclerosis Imaging and Prevention, Society for Cardiovascular Angiography and Interventions, Society of Interventional Radiology, Society of NeuroInterventional Surgery, Society for Vascular Medicine, and Society for Vascular Surgery Writing Committee Members Thomas G. Brott, Jonathan L. Halperin, Suhny Abbara, J. Michael Bacharach, John D. Barr, Ruth L. Bush, Christopher U. Cates, Mark A. Creager, Susan B. Fowler, Gary Friday, Vicki S. Hertzberg, E. Bruce McIff, Wesley S. Moore, Peter D. Panagos, Thomas S. Riles, Robert H. Rosenwasser and Allen J. Taylor Writing Committee Members , Thomas G. BrottThomas G. Brott *, †, ‡, §, ‖, ¶, #, **, ††, ‡‡, §§, ‖‖, ¶¶, ##, *** , Jonathan L. HalperinJonathan L. Halperin *, †, ‡, §, ‖, ¶, #, **, ††, ‡‡, §§, ‖‖, ¶¶, ##, *** , Suhny AbbaraSuhny Abbara *, †, ‡, §, ‖, ¶, #, **, ††, ‡‡, §§, ‖‖, ¶¶, ##, *** , J. Michael BacharachJ. Michael Bacharach *, †, ‡, §, ‖, ¶, #, **, ††, ‡‡, §§, ‖‖, ¶¶, ##, *** , John D. BarrJohn D. Barr *, †, ‡, §, ‖, ¶, #, **, ††, ‡‡, §§, ‖‖, ¶¶, ##, *** , Ruth L. BushRuth L. Bush , Christopher U. CatesChristopher U. Cates *, †, ‡, §, ‖, ¶, #, **, ††, ‡‡, §§, ‖‖, ¶¶, ##, *** , Mark A. CreagerMark A. Creager *, †, ‡, §, ‖, ¶, #, **, ††, ‡‡, §§, ‖‖, ¶¶, ##, *** , Susan B. FowlerSusan B. Fowler *, †, ‡, §, ‖, ¶, #, **, ††, ‡‡, §§, ‖‖, ¶¶, ##, *** , Gary FridayGary Friday *, †, ‡, §, ‖, ¶, #, **, ††, ‡‡, §§, ‖‖, ¶¶, ##, *** , Vicki S. HertzbergVicki S. Hertzberg , E. Bruce McIffE. Bruce McIff *, †, ‡, §, ‖, ¶, #, **, ††, ‡‡, §§, ‖‖, ¶¶, ##, *** , Wesley S. MooreWesley S. Moore , Peter D. PanagosPeter D. Panagos *, †, ‡, §, ‖, ¶, #, **, ††, ‡‡, §§, ‖‖, ¶¶, ##, *** , Thomas S. RilesThomas S. Riles *, †, ‡, §, ‖, ¶, #, **, ††, ‡‡, §§, ‖‖, ¶¶, ##, *** , Robert H. RosenwasserRobert H. Rosenwasser *, †, ‡, §, ‖, ¶, #, **, ††, ‡‡, §§, ‖‖, ¶¶, ##, *** and Allen J. TaylorAllen J. Taylor *, †, ‡, §, ‖, ¶, #, **, ††, ‡‡, §§, ‖‖, ¶¶, ##, *** Originally published31 Jan 2011https://doi.org/10.1161/STR.0b013e3182112cc2Stroke. 2011;42:e464–e540is corrected byCorrectionOther version(s) of this articleYou are viewing the most recent version of this article. Previous versions: January 1, 2011: Previous Version 1 Table of ContentsPreamble . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .e467 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .e469 1.1. Methodology and Evidence Review . . . . . . . . .e4691.2. Organization of the Writing Committee . . . . . .e4701.3. Document Review and Approval . . . . . . . . . . .e4701.4. Anatomy and Definitions . . . . . . . . . . . . . . . . .e4701.5. Epidemiology of Extracranial Cerebrovascular Disease and Stroke . . . . . . . . .e471Atherosclerotic Disease of the Extracranial Carotid and Vertebral Arteries . . . . . . . . . . . . . . . . .e472 2.1. Evaluation of Asymptomatic Patients at Risk of Extracranial Carotid Artery Disease . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .e473 2.1.1. Recommendations for Duplex Ultrasonography to Evaluate Asymptomatic Patients With Known or Suspected Carotid Stenosis. . . . . . . . .e4732.1.2. Recommendations From Other Panels . . . . . . . . . . . . . . . . . . . . . . . . . . .e4742.2. Extracranial Cerebrovascular Disease as a Marker of Systemic Atherosclerosis . . . . . . . . .e474 2.2.1. Screening for Coronary or Lower-Extremity Peripheral Arterial Disease in Patients With Atherosclerosis of the Carotid or Vertebral Arteries. . . . . . . . . . . . . . . . . . . . . . . . . .e474Clinical Presentation. . . . . . . . . . . . . . . . . . . . . . . . .e474 3.1. Natural History of Atherosclerotic Carotid Artery Disease . . . . . . . . . . . . . . . . . . .e4743.2. Characterization of Atherosclerotic Lesions in the Extracranial Carotid Arteries. . . . . . . . . .e4763.3. Symptoms and Signs of Transient Ischemic Attack and Ischemic Stroke. . . . . . . . . . . . . . . .e476 3.3.1. Public Awareness of Stroke Risk Factors and Warning Indicators . . . . . . .e476Clinical Assessment of Patients With Focal Cerebral Ischemic Symptoms . . . . . . . . . . . . . . . . . .e477 4.1. Acute Ischemic Stroke . . . . . . . . . . . . . . . . . . .e4774.2. Transient Ischemic Attack. . . . . . . . . . . . . . . . .e4774.3. Amaurosis Fugax . . . . . . . . . . . . . . . . . . . . . . .e4774.4. Cerebral Ischemia Due to Intracranial Arterial Stenosis and Occlusion . . . . . . . . . . . .e4774.5. Atherosclerotic Disease of the Aortic Arch as a Cause of Cerebral Ischemia . . . . . . .e4784.6. Atypical Clinical Presentations and Neurological Symptoms Bearing an Uncertain Relationship to Extracranial Carotid and Vertebral Artery Disease. . . . . . . . . . . . . . . . . .e478Diagnosis and Testing . . . . . . . . . . . . . . . . . . . . . . .e478 5.1. Recommendations for Diagnostic Testing in Patients With Symptoms or Signs of Extracranial Carotid Artery Disease . . . . . . . . .e4785.2. Carotid Duplex Ultrasonography. . . . . . . . . . . .e4795.3. Magnetic Resonance Angiography . . . . . . . . . .e4805.4. Computed Tomographic Angiography. . . . . . . .e4815.5. Catheter-Based Contrast Angiography. . . . . . . .e4825.6. Selection of Vascular Imaging Modalities for Individual Patients. . . . . . . . . . . . . . . . . . . .e483Medical Therapy for Patients With Atherosclerotic Disease of the Extracranial Carotid or Vertebral Arteries. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .e484 6.1. Recommendations for the Treatment of Hypertension. . . . . . . . . . . . . . . . . . . . . . . . .e4846.2. Cessation of Tobacco Smoking . . . . . . . . . . . . . . . . . . . . . . .e485 6.2.1. Recommendation for Cessation of Tobacco Smoking . . . . . . . . . . . . . . . . . .e4856.3. Control of Hyperlipidemia . . . . . . . . . . . . . . . .e485 6.3.1. Recommendations for Control of Hyperlipidemia . . . . . . . . . . . . . . . . . . . .e4856.4. Management of Diabetes Mellitus. . . . . . . . . . .e486 6.4.1. Recommendations for Management of Diabetes Mellitus in Patients With Atherosclerosis of the Extracranial Carotid or Vertebral Arteries . . . . . . . . .e4866.5. Hyperhomocysteinemia . . . . . . . . . . . . . . . . . . .e4876.6. Obesity and the Metabolic Syndrome . . . . . . . .e4876.7. Physical Inactivity. . . . . . . . . . . . . . . . . . . . . . .e4876.8. Antithrombotic Therapy . . . . . . . . . . . . . . . . . .e488 6.8.1. Recommendations for Antithrombotic Therapy in Patients With Extracranial Carotid Atherosclerotic Disease Not Undergoing Revascularization . . . . . . . .e4886.8.2. Nonsteroidal Anti-inflammatory Drugs . . . . . . . . . . . . . . . . . . . . . . . . . . .e489Revascularization . . . . . . . . . . . . . . . . . . . . . . . . . . .e490 7.1. Recommendations for Selection of Patients for Carotid Revascularization . . . . . . . . . . . . . .e4907.2. Carotid Endarterectomy. . . . . . . . . . . . . . . . . . .e490 7.2.1. Randomized Trials of Carotid Endarterectomy . . . . . . . . . . . . .e493 7.2.1.1. Carotid Endarterectomy in Symptomatic Patients . . . . . . . .e4937.2.1.2. Carotid Endarterectomy in Asymptomatic Patients . . . . . . .e4947.2.2. Factors Affecting the Outcome of Carotid Endarterectomy . . . . . . . . . . . . .e495 7.2.2.1. Technical Considerations. . . . . .e4957.2.2.2. Case Selection and Operator Experience . . . . . . . . .e4957.2.2.3. Demographic and Clinical Factors . . . . . . . . . . . . .e4957.2.3. Risks Associated With Carotid Endarterectomy . . . . . . . . . . . . .e4967.2.4. Carotid Endarterectomy in Patients With Unfavorable Anatomy . . . . . . . . . .e5007.2.5. Evolution in the Safety of Carotid Surgery . . . . . . . . . . . . . . . . . . .e5007.2.6. Evolution of Medical Therapy . . . . . . . .e5007.2.7. Recommendations for Periprocedural Management of Patients Undergoing Carotid Endarterectomy . . . . . . . . . . . . .e5017.3. Carotid Artery Stenting . . . . . . . . . . . . . . . . . . .e501 7.3.1. Multicenter Registry Studies. . . . . . . . . .e5017.3.2. Risks Associated With Carotid Artery Stenting . . . . . . . . . . . . . . . . . . . . . . . . .e502 7.3.2.1. Cardiovascular Complications . . . . . . . . . . . . . .e5027.3.2.2. Neurological Complications . . . . . . . . . . . . . .e5027.3.3. Prevention of Cerebral Embolism in Patients Undergoing Catheter-Based Carotid Intervention . . . . . . . . . . . . . . . .e5037.3.4. Intravascular Ultrasound Imaging in Conjunction With Catheter-Based Carotid Intervention . . . . . . . . . . . . . . . .e5037.3.5. Management of Patients Undergoing Endovascular Carotid Artery Stenting . . . . . . . . . . . . . . . . . . . . . . . . .e503 7.3.5.1. Recommendations for Management of Patients Undergoing Carotid Artery Stenting . . . . . . . . . . . . . . . . . . .e5037.4. Comparative Assessment of Carotid Endarterectomy and Stenting. . . . . . . . . . . . . . .e504 7.4.1. Nonrandomized Comparison of Carotid Endarterectomy With Carotid Artery Stenting . . . . . . . . . . . . . . . . . . . . . . . . .e5047.4.2. Meta-Analyses Comparing Carotid Endarterectomy and Stenting . . . . . . . . .e5057.4.3. Randomized Trials Comparing Carotid Endarterectomy and Carotid Artery Stenting . . . . . . . . . . . . . . . . . . . .e505 7.4.3.1. High-Risk Patients. . . . . . . . . . .e5057.4.3.2. Conventional-Risk Patients . . . . . . . . . . . . . . . . . . .e5057.4.4. Selection of Carotid Endarterectomy or Carotid Artery Stenting for Individual Patients With Carotid Stenosis . . . . . . . .e5077.5. Durability of Carotid Revascularization . . . . . .e507 7.5.1. Recommendations for Management of Patients Experiencing Restenosis After Carotid Endarterectomy or Stenting . . . . . . . . . . . . . . . . . . . . . . .e5077.5.2. Clinical Durability of Carotid Surgery and Carotid Stenting . . . . . . . . . . . . . . . .e5087.5.3. Anatomic Durability of Carotid Surgery and Carotid Stenting . . . . . . . . . . . . . . . .e508Vertebral Artery Disease . . . . . . . . . . . . . . . . . . . . .e509 8.1. Anatomy of the Vertebrobasilar Arterial Circulation . . . . . . . . . . . . . . . . . . . . . . . . . . . .e5098.2. Epidemiology of Vertebral Artery Disease . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .e5098.3. Clinical Presentation of Patients With Vertebrobasilar Arterial Insufficiency . . . . . . . .e5098.4. Evaluation of Patients With Vertebral Artery Disease. . . . . . . . . . . . . . . . . . . . . . . . . .e5098.5. Vertebral Artery Imaging . . . . . . . . . . . . . . . . .e509 8.5.1. Recommendations for Vascular Imaging in Patients With Vertebral Artery Disease . . . . . . . . . . . . . . . . . . . . . . . . . .e5098.6. Medical Therapy of Patients With Vertebral Artery Disease. . . . . . . . . . . . . . . . . . . . . . . . .e510 8.6.1. Recommendations for Management of Atherosclerotic Risk Factors in Patients With Vertebral Artery Disease . . . . . . . . . . . . . . . . . . . . . . . . .e5108.7. Vertebral Artery Revascularization . . . . . . . . .e511 8.7.1. Surgical Management of Vertebral Artery Disease . . . . . . . . . . . . . . . . . . .e5118.7.2. Catheter-Based Endovascular Interventions for Vertebral Artery Disease . . . . . . . . . . . . . . . . . . .e511Diseases of the Subclavian and Brachiocephalic Arteries. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .e511 9.1. Recommendations for the Management of Patients With Occlusive Disease of the Subclavian and Brachiocephalic Arteries. . . . .e5119.2. Occlusive Disease of the Subclavian and Brachiocephalic Arteries. . . . . . . . . . . . . .e5129.3. Subclavian Steal Syndrome . . . . . . . . . . . . . . .e5129.4. Revascularization of the Brachiocephalic and Subclavian Arteries. . . . . . . . . . . . . . . . . .e512Special Populations. . . . . . . . . . . . . . . . . . . . . . . . .e513 10.1. Neurological Risk Reduction in Patients With Carotid Artery Disease Undergoing Cardiac or Noncardiac Surgery . . . . . . . . . . .e513 10.1.1. Recommendations for Carotid Artery Evaluation and Revascularization Before Cardiac Surgery . . . . . . . . . . . . . . . . . . . . . . .e51310.1.2. Neurological Risk Reduction in Patients With Carotid Artery Disease Undergoing Coronary Bypass Surgery . . . . . . . . . . . . . . . . . . . . . . .e51310.1.3. Neurological Risk Reduction in Patients Undergoing Noncoronary Cardiac or Noncardiac Surgery . . . . . . . . . . . . . . . . . . . . . . .e514Nonatherosclerotic Carotid and Vertebral Artery Diseases. . . . . . . . . . . . . . . . . . . . . . . . . . . .e514 11.1. Fibromuscular Dysplasia . . . . . . . . . . . . . . . .e514 11.1.1. Recommendations for Management of Patients With Fibromuscular Dysplasia of the Extracranial Carotid Arteries. . . . . . . . . . . . . . . . .e51411.2. Cervical Artery Dissection . . . . . . . . . . . . . .e515 11.2.1. Recommendations for Management of Patients With Cervical Artery Dissection . . . . . . . . . . . . . . .e515Future Research . . . . . . . . . . . . . . . . . . . . . . . . . . .e516References. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .e518Appendix 1. Author Relationships With Industry and Other Entities. . . . . . . . . . . . . . . . . . .e534Appendix 2. Reviewer Relationships With Industry and Other Entities. . . . . . . . . . . .e536Appendix 3. Abbreviation List . . . . . . . . . . . . . . . . . . .e540Jacobs Alice K.Chair, ACCF/AHA Task Force on Practice GuidelinesSmith Sidney C.Immediate Past Chair, ACCF/AHA Task Force on Practice GuidelinesPreambleIt is essential that the medical profession play a central role in critically evaluating the evidence related to drugs, devices, and procedures for the detection, management, or prevention of disease. Properly applied, rigorous, expert analysis of the available data documenting absolute and relative benefits and risks of these therapies and procedures can improve the effectiveness of care, optimize patient outcomes, and favorably affect the cost of care by focusing resources on the most effective strategies. One important use of such data is the production of clinical practice guidelines that, in turn, can provide a foundation for a variety of other applications such as performance measures, appropriate use criteria, clinical decision support tools, and quality improvement tools.The American College of Cardiology Foundation (ACCF) and the American Heart Association (AHA) have jointly engaged in the production of guidelines in the area of cardiovascular disease since 1980. The ACCF/AHA Task Force on Practice Guidelines (Task Force) is charged with developing, updating, and revising practice guidelines for cardiovascular diseases and procedures, and the Task Force directs and oversees this effort. Writing committees are charged with assessing the evidence as an independent group of authors to develop, update, or revise recommendations for clinical practice.Experts in the subject under consideration have been selected from both organizations to examine subject-specific data and write guidelines in partnership with representatives from other medical practitioner and specialty groups. Writing committees are specifically charged to perform a formal literature review; weigh the strength of evidence for or against particular tests, treatments, or procedures; and include estimates of expected health outcomes where data exist. Patient-specific modifiers, comorbidities, and issues of patient preference that may influence the choice of tests or therapies are considered. When available, information from studies on cost is considered, but data on efficacy and clinical outcomes constitute the primary basis for recommendations in these guidelines.In analyzing the data and developing the recommendations and supporting text, the writing committee used evidence-based methodologies developed by the Task Force that are described elsewhere.1 The committee reviewed and ranked evidence supporting current recommendations with the weight of evidence ranked as Level A if the data were derived from multiple randomized clinical trials or meta-analyses. The committee ranked available evidence as Level B when data were derived from a single randomized trial or nonrandomized studies. Evidence was ranked as Level C when the primary source of the recommendation was consensus opinion, case studies, or standard of care. In the narrative portions of these guidelines, evidence is generally presented in chronological order of development. Studies are identified as observational, retrospective, prospective, or randomized when appropriate. For certain conditions for which inadequate data are available, recommendations are based on expert consensus and clinical experience and ranked as Level C. An example is the use of penicillin for pneumococcal pneumonia, for which there are no randomized trials and treatment is based on clinical experience. When recommendations at Level C are supported by historical clinical data, appropriate references (including clinical reviews) are cited if available. For issues where sparse data are available, a survey of current practice among the clinicians on the writing committee was the basis for Level C recommendations, and no references are cited. The schema for Classification of Recommendations and Level of Evidence is summarized in Table 1, which also illustrates how the grading system provides an estimate of the size and the certainty of the treatment effect. A new addition to the ACCF/AHA methodology is a separation of the Class III recommendations to delineate whether the recommendation is determined to be of "no benefit" or associated with "harm" to the patient. In addition, in view of the increasing number of comparative effectiveness studies, comparator verbs and suggested phrases for writing recommendations for the comparative effectiveness of one treatment/strategy with respect to another for Class of Recommendation I and IIa, Level of Evidence A or B only have been added.Table 1. Applying Classification of Recommendations and Level of EvidenceTable 1. Applying Classification of Recommendations and Level of Evidence*Data available from clinical trials or registries about the usefulness/efficacy in different subpopulations, such as gender, age, history of diabetes, history of prior myocardial infarction, history of heart failure, and prior aspirin use. A recommendation with Level of Evidence B or C does not imply that the recommendation is weak. Many important clinical questions addressed in the guidelines do not lend themselves to clinical trials. Even though randomized trials are not available, there may be a very clear clinical consensus that a particular test or therapy is useful or effective.†For comparative effectiveness recommendations (Class I and IIa; Level of Evidence: A and B only), studies that support the use of comparator verbs should involve direct comparisons of the treatments or strategies being evaluated.The Task Force makes every effort to avoid actual, potential, or perceived conflicts of interest that may arise as a result of relationships with industry or other entities (RWI) among the writing committee. Specifically, all members of the writing committee, as well as peer reviewers of the document, are asked to disclose all current relationships and those 24 months before initiation of the writing effort that may be perceived as relevant. All guideline recommendations require a confidential vote by the writing committee and must be approved by a consensus of the members voting. Any writing committee member who develops a new RWI during his or her tenure is required to notify guideline staff in writing. These statements are reviewed by the Task Force and all members during each conference call and/or meeting of the writing committee and are updated as changes occur. For detailed information about guideline policies and procedures, please refer to the ACCF/AHA methodology and policies manual.1 Authors' and peer reviewers' RWI pertinent to this guideline are disclosed in Appendixes 1 and 2, respectively. Disclosure information for the ACCF/AHA Task Force on Practice Guidelines is also available online at www.cardiosource.org/ACC/About-ACC/Leadership/Guidelines-and-Documents-Task-Forces.aspx. The work of the writing committee was supported exclusively by the ACCF and AHA (and the other partnering organizations) without commercial support. Writing committee members volunteered their time for this effort.The ACCF/AHA practice guidelines address patient populations (and healthcare providers) residing in North America. As such, drugs that are currently unavailable in North America are discussed in the text without a specific class of recommendation. For studies performed in large numbers of subjects outside of North America, each writing committee reviews the potential impact of different practice patterns and patient populations on the treatment effect and the relevance to the ACCF/AHA target population to determine whether the findings should inform a specific recommendation.The ACCF/AHA practice guidelines are intended to assist healthcare providers in clinical decision making by describing a range of generally acceptable approaches for the diagnosis, management, and prevention of specific diseases or conditions. These practice guidelines represent a consensus of expert opinion after a thorough review of the available current scientific evidence and are intended to improve patient care. The guidelines attempt to define practices that meet the needs of most patients in most circumstances. The ultimate judgment regarding care of a particular patient must be made by the healthcare provider and patient in light of all the circumstances presented by that patient. Thus, there are situations in which deviations from these guidelines may be appropriate. Clinical decision making should consider the quality and availability of expertise in the area where care is provided. When these guidelines are used as the basis for regulatory or payer decisions, the goal should be improvement in quality of care. The Task Force recognizes that situations arise for which additional data are needed to better inform patient care; these areas will be identified within each respective guideline when appropriate.Prescribed courses of treatment in accordance with these recommendations are effective only if they are followed. Because lack of patient understanding and adherence may adversely affect outcomes, physicians and other healthcare providers should make every effort to engage the patient's active participation in prescribed medical regimens and lifestyles.The guidelines will be reviewed annually by the Task Force and considered current unless they are updated, revised, or withdrawn from distribution. The executive summary and recommendations are published in the Journal of the American College of Cardiology, Circulation, Stroke, Catheterization and Cardiovascular Interventions, the Journal of Cardiovascular Computed Tomography, the Journal of NeuroInterventional Surgery, and Vascular Medicine.1. Introduction1.1. Methodology and Evidence ReviewThe ACCF/AHA writing committee to create the 2011 Guideline on the Management of Patients With Extracranial Carotid and Vertebral Artery Disease (ECVD) conducted a comprehensive review of the literature relevant to carotid and vertebral artery interventions through May 2010.The recommendations listed in this document are, whenever possible, evidence-based. Searches were limited to studies, reviews, and other evidence conducted in human subjects and published in English. Key search words included but were not limited to angioplasty, atherosclerosis, carotid artery disease, carotid endarterectomy (CEA), carotid revascularization, carotid stenosis, carotid stenting, carotid artery stenting (CAS), extracranial carotid artery stenosis, stroke, transient ischemic attack (TIA), and vertebral artery disease. Additional searches cross-referenced these topics with the following subtopics: acetylsalicylic acid, antiplatelet therapy, carotid artery dissection, cerebral embolism, cerebral protection, cerebrovascular disorders, complications, comorbidities, extracranial atherosclerosis, intima-media thickness (IMT), medical therapy, neurological examination, noninvasive testing, pharmacological therapy, preoperative risk, primary closure, risk factors, and vertebral artery dissection. Additionally, the committee reviewed documents related to the subject matter previously published by the ACCF and AHA (and other partnering organizations). References selected and published in this document are representative and not all-inclusive.To provide clinicians with a comprehensive set of data, whenever deemed appropriate or when published in the article, data from the clinical trials were used to calculate the absolute risk difference and number needed to treat (NNT) or harm; data related to the relative treatment effects are also provided, such as odds ratio (OR), relative risk (RR), hazard ratio (HR), or incidence rate ratio, along with confidence interval (CI) when available.The committee used the evidence-based methodologies developed by the Task Force and acknowledges that adjudication of the evidence was complicated by the timing of the evidence when 2 different interventions were contrasted. Despite similar study designs (eg, randomized controlled trials), research on CEA was conducted in a different era (and thus, evidence existed in the peer-reviewed literature for more time) than the more contemporary CAS trials. Because evidence is lacking in the literature to guide many aspects of the care of patients with nonatherosclerotic carotid disease and most forms of vertebral artery disease, a relatively large number of the recommendations in this document are based on consensus.The writing committee chose to limit the scope of this document to the vascular diseases themselves and not to the management of patients with acute stroke or to the detection or prevention of disease in individuals or populations at risk, which are covered in another guideline.2 The full-text guideline is based on the presumption that readers will search the document for specific advice on the management of patients with ECVD at different phases of illness. Following the typical chronology of the clinical care of patients with ECVD, the guideline is organized in sections that address the pathogenesis, epidemiology, diagnostic evaluation, and management of patients with ECVD, including prevention of recurrent ischemic events. The text, recommendations, and supporting evidence are intended to assist the diverse array of clinicians who provide care for patients with ECVD. In particular, they are designed to aid primary care clinicians, medical and surgical cardiovascular specialists, and trainees in the primary care and vascular specialties, as well as nurses and other healthcare personnel who seek clinical tools to promote the proper evaluation and management of patients with ECVD in both inpatient and outpatient settings. Application of the recommended diagnostic and therapeutic strategies, combined with careful clinical judgment, should improve diagnosis of each syndrome, enhance prevention, and decrease rates of stroke and related long-term disability and death. The ultimate goal of the guideline statement is to improve the duration and quality of life for people with ECVD.1.2. Organization of the Writing CommitteeThe writing committee to develop the 2011 ASA/ACCF/AHA/AANN/AANS/ACR/ASNR/CNS/SAIP/SCAI/SIR/SNIS/SVM/SVS Guideline on the Management of Patients With Extracranial Carotid and Vertebral Artery Disease was composed of experts in the areas of medicine, surgery, neurology, cardiology, radiology, vascular surgery, neurosurgery, neuroradiology, interventional radiology, noninvasive imaging, emergency medicine, vascular medicine, nursing, epidemiology, and biostatistics. The committee included representatives of the American Stroke Association (ASA), ACCF, AHA, American Academy of Neurology (AAN), American Association of Neuroscience Nurses (AANN), American Association of Neurological Surgeons (AANS), American College of Emergency Physicians (ACEP), American College of Radiology (ACR), American Society of Neuroradiology (ASNR), Congress of Neurological Surgeons (CNS), Society of Atherosclerosis Imaging and Prevention (SAIP), Society for Cardiovascular Angiography and Interventions (SCAI), Society of Cardiovascular Computed Tomography (SCCT), Society of Interventional Radiology (SIR), Society of NeuroInterventional Surgery (SNIS), Society for Vascular Medicine (SVM), and Society for Vascular Surgery (SVS).1.3. Document Review and ApprovalThe document was reviewed by 55 external reviewers, including individuals nominated by each of the ASA, ACCF, AHA, AANN, AANS, ACEP, American College of Physicians, ACR, ASNR, CNS, SAIP, SCAI, SCCT, SIR, SNIS, SVM, and SVS, and by individual content reviewers, including members from the ACCF Cathe