StrokeAHA SCIENTIFIC STATEMENTDiagnosis,Workup,Risk Reduction of TransientIschemic Attack in the Emergency DepartmentSetting:A Scientific Statement From theAmerican Heart AssociationHardik P.Amin,MD,Chair;Tracy E Madsen,MD,PhD,Vice Chair;Dawn M.Bravata,MD;Charles R.Wira,MD;S.Claiborne Johnston,MD,PhD;Susan Ashcraft,DNP;Tamika M.Burrus,MD;Peter D.Panagos,MD;Max Wintermark,MD,MAS;Charles Esenwa,MD,MS;on behalf of the American Heart Association Emergency NeurovascularCare Committee of the Stroke Council and Council on Peripheral Vascular DiseaseABSTRACT:At least 240000 individuals experience a transient ischemic attack each year in the United States.Transientischemic attack is a strong predictor of subsequent stroke.The 90-day stroke risk after transient ischemic attack canbe as high as 178%,with almost half occurring within 2 days of the index event.Diagnosing transient ischemic attackcan also be challenging given the transitory nature of symptoms,often reassuring neurological examination at the timeof evaluation,and lack of confirmatory testing.Limited resources,such as imaging availability and access to specialists,can further exacerbate this challenge.This scientific statement focuses on the correct clinical diagnosis,risk assessment,and management decisions of patients with suspected transient ischemic attack.Identification of high-risk patients canbe achieved through use of comprehensive protocols incorporating acute phase imaging of both the brain and cerebralvasculature,thoughtful use of risk stratification scales,and ancillary testing with the ultimate goal of determining who canbe safely discharged home from the emergency department versus admitted to the hospital.We discuss various methods forrapid yet comprehensive evaluations,keeping resource-limited sites in mind.In addition,we discuss strategies for secondaryprevention of future cerebrovascular events using maximal medical therapy and patient education.Key Words:AHA Scientific Statements atrial fibrillation cerebral angiography diffusion magnetic resonance imaging■emergency service,hospital■ischemic attack,.transient■strokeransient ischemic attack (TIA)is clinically describedimaging (DWI)MRI.A patient with resolved symptomsas an acute onset of focal neurological symptomsand MRI demonstrating infarct should be diagnosed withfollowed by complete resolution.TIA has been rec-an ischemic stroke.ognized as a risk factor for future stroke since the 1950s.Use of a time-based versus tissue-based definition forTIA has been debated since the 1980s and intensifiedEPIDEMIOLOGYwith the widespread availability of magnetic resonanceThe true incidence of TIA in the United States is difficultimaging (MRI).12 In 2009,the American Heart Associa-to determine given its transitory nature and the lack oftion redefined TIA using a tissue-based approach (ie,standardized national surveillance systems.In addition,symptom resolution plus absence of infarction on brainlack of symptom recognition by the public sugg
