Thomas G. Brott

Guidelines for Carotid Endarterectomy A Multidisciplinary Consensus Statement From the Ad Hoc Committee, American Heart Association

BACKGROUND AND PURPOSEnIndications for carotid endarterectomy have engendered considerable debate among experts and have resulted in publication of retrospective reviews, natural history studies, audits of community practice, position papers, expert opinion statements, and finally prospective randomized trials. The American Heart Association assembled a group of experts in a multidisciplinary consensus conference to develop this statement.nnnMETHODSnA conference was held July 16-18, 1993, in Park City, Utah, that included recognized experts in neurology, neurosurgery, vascular surgery, and healthcare planning. A program of critical topics was developed, and each expert presented a talk and provided the chairman with a summary statement. From these summary statements a document was developed and edited onsite to achieve consensus before final revision.nnnRESULTSnThe first section of this document reviews the natural history, methods of patient evaluation, options for medical management, results of surgical management, data from position statements, and results to date of prospective randomized trials for symptomatic and asymptomatic patients with carotid artery disease. The second section divides 96 potential indications for carotid endarterectomy, based on surgical risk, into four categories: (1) Proven: This is the strongest indication for carotid endarterectomy; data are supported by results of prospective contemporary randomized trials. (2) Acceptable but not proven: a good indication for operation; supported by promising but not scientifically certain data. (3) Uncertain: Data are insufficient to define the risk/benefit ratio. (4) Proven inappropriate: Current data are adequate to show that the risk of surgery outweighs any benefit.nnnCONCLUSIONSnIndications for carotid endarterectomy in symptomatic good-risk patients with a surgeon whose surgical morbidity and mortality rate is less than 6% are as follows. (1) Proven: one or more TIAs in the past 6 months and carotid stenosis > or = 70% or mild stroke within 6 months and a carotid stenosis > or = 70%; (2) acceptable but not proven: TIAs within the past 6 months and a stenosis 50% to 69%, progressive stroke and a stenosis > or = 70%, mild or moderate stroke in the past 6 months and a stenosis 50% to 69%, or carotid endarterectomy ipsilateral to TIAs and a stenosis > or = 70% combined with required coronary artery bypass grafting; (3) uncertain: TIAs with a stenosis < 50%, mild stroke and stenosis < 50%, TIAs with a stenosis < 70% combined with coronary artery bypass grafting, or symptomatic, acute carotid thrombosis; (4) proven inappropriate: moderate stroke with stenosis < 50%, not on aspirin; single TIA, < 50% stenosis, not on aspirin; high-risk patient with multiple TIAs, not on aspirin, stenosis < 50%; high-risk patient, mild or moderate stroke, stenosis < 50%, not on aspirin; global ischemic symptoms with stenosis < 50%; acute dissection, asymptomatic on heparin. Indications for carotid endarterectomy in asymptomatic good-risk patients performed by a surgeon whose surgical morbidity and mortality rate is less than 3% are as follows. (1) Proven: none. As this statement went to press, the National Institute of Neurological Disorders and Stroke issued a clinical advisory stating that the Institute has halted the Asymptomatic Carotid Atherosclerosis Study (ACAS) because of a clear benefit in favor of surgery for patients with carotid stenosis > or = 60% as measured by diameter reduction. When the ACAS report is published, this indication will be recategorized as proven. (2) acceptable but not proven: stenosis > 75% by linear diameter; (3) uncertain: stenosis > 75% in a high-risk patient/surgeon (surgical morbidity and mortality rate > 3%), combined carotid/coronary operations, or ulcerative lesions without hemodynamically significant stenosis; (4) proven inappropriate: operations with a combined stroke morbidity and mortality > 5%.

Guidelines for Thrombolytic Therapy for Acute Stroke: A Supplement to the Guidelines for the Management of Patients With Acute Ischemic Stroke A Statement for Healthcare Professionals From a Special Writing Group of the Stroke Council, American Heart Association

In 1994 a panel of the American Heart Association Stroke Council wrote guidelines on the management of patients with acute ischemic stroke.1 The panel predicted that its recommendations would change as the results of ongoing clinical trials became available. At that time the panel recommended that thrombolytic drugs should not be given to persons with acute ischemic stroke outside the clinical trial setting. Since publication of the guidelines, the results of five clinical trials of intravenously administered thrombolytic drugs have been reported.2 3 4 5 6 The use of intra-arterial thrombolytic drugs continues to be reported. In light of these data, the Stroke Council reviewed the status of thrombolytic therapy and prepared this supplement, which includes recommendations for the use of thrombolytic drugs in clinical practice. In preparing this report, panel members used the rules of evidence for treatments used during the writing of the previous report1 7 (Table 1⇓). The target audience for this statement includes neurologists, emergency physicians, primary care physicians, neurosurgeons, and vascular surgeons who care for persons seen within the first few hours after stroke.nnView this table:nn Table 1. nLevels of Evidence and Grading of Recommendations for Treatment of Patients With Acute Ischemic Stroke*nnnnMeasures to expedite clot lysis and restore circulation may limit the extent of brain injury and improve outcome after stroke. Unfortunately, intracranial bleeding was frequent among persons enrolled in studies performed in the late 1960s and 1970s, and the therapy was abandoned8 9 10 (Level of Evidence II). More recently, interest in thrombolytic therapy revived because of development of new drugs and their successful use in the care of persons with myocardial ischemia.11 In addition, a meta-analysis combining data from several pilot studies in stroke suggested that thrombolytic therapy might be useful.12 Available thrombolytic drugs are recombinant tissue plasminogen …

Guidelines for the management of patients with acute ischemic stroke. A statement for healthcare professionals from a special writing group of the Stroke Council, American Heart Association.

In 1991, about 500 000 Americans had a stroke (400 000 had an ischemic stroke) and more than 143 000 died. More than 3 000 000 people in the .Ignited States have survived a stroke. In 1994 the annual economic costs of stroke due to health care expenses and lost productivity are estimated to be nearly

Guidelines for Carotid Endarterectomy A Statement for Healthcare Professionals From a Special Writing Group of the Stroke Council, American Heart Association

20 billion. In spite of these human and financial costs, stroke unfortunately has not received a great deal of attention, and its management has been marred by an element of nihilism. Caplan concludes that past failures to establish effective therapies for stroke are due to problems in clinical trial design, lack of interest in care of stroke, and lack of available technologies to evaluate patients. However, with advances in diagnosis and treatment, stroke can now be managed as the life-threatening emergency that it is. In 1993 the American Heart Association included emergent stroke care as part of its special resuscitation situations for basic and advanced life support. This report builds on that statement. The goal of this special report is to provide information about the current management of acute ischemic stroke. It also provides recommendations for initial care (within 24 hours of stroke) based on currently available data from clinical trials. In the future, many therapies for stroke will be linked to very early (within 6 hours) intervention. No recommendations about rehabilitation or chronic medical or surgical measures to prevent recurrent stroke are made. To prepare this report, the members of the Stroke Council used the rules of evidence for specific treatments that have been used by other panels (Table I). These rules give greater credence to the results of well-designed clinical trials than to anecdotal case reports or case series. The current recommendations will eventually be altered

Identification and entry of the patient with acute cerebral infarction.

Since the 1950s carotid endarterectomy has been performed in patients with symptomatic carotid artery stenosis, based on suggestive but inconclusive evidence for its effectiveness. Only during the last 5 years have randomized studies clarified the indications for surgery. In preparing this report, panel members used the same rules of evidence used in the previous report1 2 (Table⇓).nnView this table:nn Table 1. nLevels of Evidence and Grading of RecommendationsnnnnFew studies have analyzed control of risk factors in a randomized, prospective manner following carotid endarterectomy. However, a wealth of data are available regarding the general relationship between risk factor control and stroke risk. These data provide some guidance for the care of endarterectomy patients.nn### HypertensionnnHypertension is the most powerful, prevalent, and treatable risk factor for stroke.3 Both systolic and diastolic blood pressure are independently related to stroke incidence. Isolated systolic hypertension, which is common in the elderly, also considerably increases risk of stroke. Reduction of elevated blood pressure significantly lowers risk of stroke. Meta-analyses of randomized trials found that an average reduction in diastolic blood pressure of 6 mm Hg produces a 42% reduction in stroke incidence.3 4 Treatment of isolated systolic hypertension in people older than 60 years also reduces stroke incidence by 36% without an excessive number of side effects such as depression or dementia.5 Long-term care of patients after endarterectomy should include careful control of hypertension (Grade A recommendation for treatment of hypertension in general; Grade C recommendation for postendarterectomy care).nnPerioperative treatment of hypertension after carotid endarterectomy represents a special situation. Poor control of blood pressure after endarterectomy increases risk of cerebral hyperperfusion syndrome.6 7 8 9 This complication is characterized by unilateral headache, seizures, and occasionally altered mental status or focal neurological signs. Neuroimaging may show intracerebral hemorrhages10 11 12 or white …

Comparison of admission serum glucose concentration with neurologic outcome in acute cerebral infarction. A study in patients given naloxone

Although time has been recognized as a critical factor in the treatment of other arterial occlusive disorders, it has been an underemphasized variable in the treatment of acute stroke. Animal models of cerebral arterial occlusion have demonstrated that neurologic recovery is more likely the shorter the duration of occlusion. Complete recovery does not occur if the occlusion persists more than six hours. Prior trials have only rarely begun treatment within six hours of stroke onset. Over the past five years, we have participated in three stroke trials and have tried to identify factors that lead to delays in treatment. Factors that affect the time from stroke onset to arrival at the hospital include recognition of acute stroke by the patient, prehospital care personnel, and physicians. After arrival at the hospital, factors that can significantly delay treatment include the time to obtain computed tomography and the site of treatment (emergency department vs ICU). With proper attention, the time from patient arrival until treatment should be less than one hour. Future efforts should be directed toward reducing the time from stroke onset until arrival at the hospital. Education of the public, high-risk patients, prehospital care providers, and physicians may aid in these efforts.

Effect of treatment delay, age, and stroke severity on the effects of intravenous thrombolysis with alteplase for acute ischaemic stroke: a meta-analysis of individual patient data from randomised trials | NOVA. The University of Newcastle's Digital Repository

We studied the ability of serum glucose concentration and neurologic deficits at admission in predicting the outcome of acute cerebral ischemia in 65 patients given naloxone. Among our patients, the volume of infarction on computed tomograms and outcome were strongly related to the severity of neurologic deficits found at admission. Neither a history of diabetes nor hyperglycemia when added to the results of the initial neurologic assessment improved prediction of outcome after acute cerebral infarction.