John J. Connors

An Updated Definition of Stroke for the 21st Century A Statement for Healthcare Professionals From the American Heart Association/American Stroke Association

Despite the global impact and advances in understanding the pathophysiology of cerebrovascular diseases, the term “stroke” is not consistently defined in clinical practice, in clinical research, or in assessments of the public health. The classic definition is mainly clinical and does not account for advances in science and technology. The Stroke Council of the American Heart Association/American Stroke Association convened a writing group to develop an expert consensus document for an updated definition of stroke for the 21st century. Central nervous system infarction is defined as brain, spinal cord, or retinal cell death attributable to ischemia, based on neuropathological, neuroimaging, and/or clinical evidence of permanent injury. Central nervous system infarction occurs over a clinical spectrum: Ischemic stroke specifically refers to central nervous system infarction accompanied by overt symptoms, while silent infarction by definition causes no known symptoms. Stroke also broadly includes intracerebral hemorrhage and subarachnoid hemorrhage. The updated definition of stroke incorporates clinical and tissue criteria and can be incorporated into practice, research, and assessments of the public health.

Recommendations for Comprehensive Stroke Centers: A Consensus Statement From the Brain Attack Coalition

Background and Purpose— To develop recommendations for the establishment of comprehensive stroke centers capable of delivering the full spectrum of care to seriously ill patients with stroke and cerebrovascular disease. Recommendations were developed by members of the Brain Attack Coalition (BAC), which is a multidisciplinary group of members from major professional organizations involved with the care of patients with stroke and cerebrovascular disease. Summary of Review— A comprehensive literature search was conducted from 1966 through December 2004 using Medline and Pub Med. Articles with information about clinical trials, meta-analyses, care guidelines, scientific guidelines, and other relevant clinical and research reports were examined and graded using established evidence-based medicine approaches for therapeutic and diagnostic modalities. Evidence was also obtained from a questionnaire survey sent to leaders in cerebrovascular disease. Members of BAC reviewed literature related to their field and graded the scientific evidence on the various diagnostic and treatment modalities for stroke. Input was obtained from the organizations represented by BAC. BAC met on several occasions to review each specific recommendation and reach a consensus about its importance in light of other medical, logistical, and financial factors. Conclusions— There are a number of key areas supported by evidence-based medicine that are important for a comprehensive stroke center and its ability to deliver the wide variety of specialized care needed by patients with serious cerebrovascular disease. These areas include: (1) health care personnel with specific expertise in a number of disciplines, including neurosurgery and vascular neurology; (2) advanced neuroimaging capabilities such as MRI and various types of cerebral angiography; (3) surgical and endovascular techniques, including clipping and coiling of intracranial aneurysms, carotid endarterectomy, and intra-arterial thrombolytic therapy; and (4) other specific infrastructure and programmatic elements such as an intensive care unit and a stroke registry. Integration of these elements into a coordinated hospital-based program or system is likely to improve outcomes of patients with strokes and complex cerebrovascular disease who require the services of a comprehensive stroke center.

Recommendations for Imaging of Acute Ischemic Stroke A Scientific Statement From the American Heart Association

Stroke is a common and serious disorder, with an incidence of ≈795 000 each year in the United States alone. Worldwide, stroke is a leading cause of death and disability. Recombinant tissue plasminogen activator (rtPA) was approved a decade ago for the treatment of acute ischemic stroke. The guidelines for its use include stroke onset within 3 hours of intravenous drug administration, preceded by a computed tomographic (CT) scan to exclude the presence of hemorrhage, which is a contraindication to the use of the drug. Although randomized, controlled studies in Europe and North America demonstrated the efficacy of this treatment, it also was associated with an incidence of intracranial hemorrhage of 6.4%,1,2⇓ which was shown on subsequent studies to be even greater if there was not strict adherence to the administration protocol.3 The goal of these controlled studies was to evaluate patient outcome. There was no attempt to determine the site, or even the actual presence, of a vascular occlusion, the degree of tissue injury, or the amount of tissue at risk for further injury that might be salvageable. More than a decade later, progress for treating acute ischemic stroke has been slow,4,5⇓ yet the goals for treating this common disease have expanded. First, there is the need to extend the therapeutic window from 3 to ≥6 hours. Even with the rapid communication and transportation in our societies today, very few patients present for treatment within 3 hours.6 Second, there is the desire to improve the efficacy of treatment. It had been shown even before the randomized, controlled studies that intravenous rtPA works better in small peripheral vessels than in the large vessels at the skull base.7 Third, there is a need to decrease the complication rate, especially if patients are to be …

Angioplasty for Symptomatic Intracranial Stenosis: Clinical Outcome

Background and Purpose— Medical treatment of symptomatic intracranial stenosis carries a high risk of stroke. This study was done to evaluate the clinical and angiographic outcomes after intracranial angioplasty for this disease. Methods— A total of 120 patients with 124 intracranial stenoses were treated by primary angioplasty. All patients had neurologic symptoms (stroke or transient ischemic attack) attributable to intracranial stenoses ≥50%. Angiograms were evaluated before and after angioplasty for the degree of stenosis. Results— Pretreatment stenoses varied from 50% to 95% (mean 82.2±10.2). Post-treatment stenoses varied from 0% to 90% (mean 36.0±20.1). There were 3 strokes and 4 deaths (all neurological) within 30 days of the procedure, giving a combined periprocedural stroke and death rate of 5.8%. A total of 116 patients (96.7%) were available for a mean follow-up time of 42.3 months. There were 6 patients who had a stroke in the territory of treatment and 5 additional patients with stroke in other territories. Ten deaths occurred during the follow-up period, none of which were neurological. Including the periprocedural stroke and deaths, this yielded an annual stroke rate of 3.2% in the territory of treatment and a 4.4% annual rate for all strokes. Conclusion— Intracranial angioplasty can be performed with a high degree of technical success and a low risk of complications. Long-term clinical follow-up of intracranial angioplasty patients demonstrates a risk of future strokes that compares favorably to patients receiving medical therapy.

Metrics for Measuring Quality of Care in Comprehensive Stroke Centers: Detailed Follow-Up to Brain Attack Coalition Comprehensive Stroke Center Recommendations A Statement for Healthcare Professionals From the American Heart Association/American Stroke Association

Background— Stroke is a major cause of disability and death. The Brain Attack Coalition has proposed establishment of primary and comprehensive stroke centers to provide appropriate care to stroke patients who require basic and more advanced interventions, respectively. Primary stroke centers have been designated by The Joint Commission since 2003, as well as by various states. The designation of comprehensive stroke centers (CSCs) is now being considered. To assist in this process, we propose a set of metrics and related data that CSCs should track to monitor the quality of care that they provide and to facilitate quality improvement. Methods and Results— We analyzed available guideline statements, reviews, and other literature to identify the major features that distinguish CSCs from primary stroke centers, drafted a set of metrics and related data elements to measure the key components of these aspects of stroke care, and then revised these through an iterative process to reach a consensus. We propose a set of metrics and related data elements that cover the major aspects of specialized care for patients with ischemic cerebrovascular disease and nontraumatic subarachnoid and intracerebral hemorrhages at CSCs. Conclusions— The metrics that we propose are intended to provide a framework for standardized data collection at CSCs to facilitate local quality improvement efforts and to allow for analysis of pooled data from different CSCs that may lead to development of national performance standards for CSCs in the future.

Training, competency, and credentialing standards for diagnostic cervicocerebral angiography, carotid stenting, and cerebrovascular intervention A Joint Statement from the American Academy of Neurology, the American Association of Neurological Surgeons, the American Society of Interventional and Therapeutic Neuroradiology, the American Society of Neuroradiology, the Congress of Neurological Surgeons, the AANS/CNS Cerebrovascular Section, and the Society of Interventional Radiology*

Appropriate and adequate cognitive and technical training, proficiency and experience are essential for the safe performance of procedures that confer significant risk to patient well-being. This principle is the foundation of all medical education and is especially important when considering the cerebral vasculature, for which stroke is a defined risk for every endovascular procedure. Despite recent advances in noninvasive diagnostic neuroimaging, diagnostic cervicocerebral angiography remains the cornerstone and “gold standard” for the evaluation and treatment of patients with cerebrovascular disease.1 In addition to a high level of technical expertise, performance and interpretation of diagnostic cervicocerebral angiography requires in-depth cognitive knowledge of related neurological pathophysiology, neurovascular anatomy and pathology, and an understanding of the full range of neurodiagnostic possibilities. Expert diagnostic cervicocerebral angiography is the foundation for safe and successful cervicocerebral endovascular intervention, including carotid artery angioplasty and stenting for atherosclerosis, interventional stroke therapy, intracranial angioplasty and stenting, and embolization of cerebral aneurysms, epistaxis and vascular malformations. All of these procedures are increasing in volume and complexity with recent technological advances that further mandate the need for adequate cognitive acumen and technical skills. To ensure proper outcomes, formal neuroscience training, adequate procedural training and sufficient experience are all essential for competency in diagnostic cervicocerebral angiography and interventional procedures, including carotid stenting. These concepts have been delineated in training requirements by the Accreditation Council for Graduate Medical Education (ACGME) and by previously published official society statements. The purpose of this document is to define the minimum training and experience necessary to provide adequate quality of patient care for extracranial cerebrovascular interventions, particularly carotid artery stenting. Hospital credentialing is the mechanism by which competence is ensured. ### Risks of diagnostic cervicocerebral angiography. Stroke is recognized as the most disabling and costly of all medical conditions.2 Stroke is also the most feared of all iatrogenic medical and procedural …

Routine Clinical Evaluation of Cerebrovascular Reserve Capacity Using Carbogen in Patients With Intracranial Stenosis

Background and Purpose— A promising method for identifying hemodynamic impairment that may serve as a biomarker for stroke risk in patients with intracranial stenosis is cerebrovascular reactivity (CVR) mapping using noninvasive MRI. Here, abilities to measure CVR safely in the clinic using hypercarbic hyperoxic (carbogen) gas challenges, which increase oxygen delivery to tissue, are investigated. Methods— In sequence with structural and angiographic imaging, blood oxygenation level–dependent carbogen-induced CVR scans were performed in patients with symptomatic intracranial stenosis (n=92) and control (n=10) volunteers, with a subgroup of patients (n=57) undergoing cerebral blood flow–weighted pseudocontinuous arterial spin labeling CVR. Subjects were stratified for 4 substudies to evaluate relationships between (1) carbogen and hypercarbic normoxic CVR in healthy tissue (n=10), (2) carbogen cerebral blood flow CVR and blood oxygenation level–dependent CVR in intracranial stenosis patients (n=57), (3) carbogen CVR and clinical measures of disease in patients with asymmetrical intracranial atherosclerotic (n=31) and moyamoya (n=29) disease, and (4) the CVR scan and immediate and longer-term complications (n=92). Results— Noninvasive blood oxygenation level–dependent carbogen-induced CVR values correlate with (1) lobar hypercarbic normoxic gas stimuli in healthy tissue (R=0.92; P<0.001), (2) carbogen-induced cerebral blood flow CVR in patients with intracranial stenosis (R=0.30–0.33; P<0.012), and (3) angiographic measures of disease severity both in atherosclerotic and moyamoya patients after appropriate processing. No immediate stroke-related complications were reported in response to carbogen administration; longer-term neurological events fell within the range for expected events in this patient population. Conclusions— Carbogen-induced CVR elicited no added adverse events and provided a surrogate marker of cerebrovascular reserve consistent with intracranial vasculopathy.

Quality Improvement Guidelines for the Performance of Cervical Carotid Angioplasty and Stent Placement

Developed by a Collaborative Panel of the American Society of Interventional and Therapeutic Neuroradiology, the American Society of Neuroradiology, and the Society of Interventional Radiology

Quality improvement guidelines for the performance of cervical carotid angioplasty and stent placement: Developed by a collaborative panel of the American Society of Interventional and Therapeutic Neuroradiology, the American Society of Neuroradiology, and the Society of Interventional Radiology

John D. Barr, MD, John J. Connors, III, MD, David Sacks, MD, Joan C. Wojak, MD, Gary J. Becker, MD, John F. Cardella, MD, Bohdan Chopko, MD, PhD, Jacques E. Dion, MD, Allan J. Fox, MD, Randall T. Higashida, MD, Robert W. Hurst, MD, Curtis A. Lewis, MD, MBA, Terence A.S. Matalon, MD, Gary M. Nesbit, MD, J. Arliss Pollock, MD, Eric J. Russell, MD, David J. Seidenwurm, MD, and Robert C. Wallace, MD, for the ASITN, ASNR, and SIR Standards of Practice Committees

Intracranial angioplasty and stenting for cerebral atherosclerosis: a position statement of the American Society of Interventional and Therapeutic Neuroradiology, Society of Interventional Radiology, and the American Society of Neuroradiology.

From the Departments of Radiology, Neurology, Neurological Surgery, and Anesthesiology Neurointerventional Radiology Division (R.T.H.), University of California, San Francisco Medical Center, San Francisco, California; Departments of Radiology and Neurological Surgery Neuroendovascular Service (P.M.M.), Columbia University Medical Center, 710 West 168 Street, Rm 404, New York, NY 10032; Interventional Neuroradiology Division (J.J.C.), Baptist Hospital of Miami, Miami, Florida; Department of Radiology (D.S.), Reading Hospital and Medical Center, West Reading, Pennsylvania; Department of Radiology and Division of Interventional Neuroradiology (C.M.S.), Methodist Hospital, Houston, Texas; Interventional Neuroradiology (J.D.B), Baptist Memorial Hospitals, Memphis, Tennessee; Interventional Neuroradiology (J.C.W.), Our Lady of Lourdes Regional Medical Center, Lafayette, Louisiana; Department of Radiology and Division of Endovascular Neuroradiology (G.R.D.), University of California, Los Angeles, Los Angeles, California. Address correspondence to P.M.M., Departments of Radiology and Neurological Surgery Neuroendovascular Service, Columbia University Medical Center, 710 West 168th Street, Rm 404, New York, NY 10032.