Difinition and evaluation of transient ischemic attack A scientific statement for healthcare professionals from the American Heart Association/American Stroke Association Stroke Council；Council on Cardiovascular Surgery and Anesthesia；Council on Cardiovascular Radiology and Intervention；Council on Cardiovascular Nursing；and the Inerdisciplinary Council on Peripheral Vascular Disease The American Academy of Neurology affirms the value of this statement as an educational tool for neurologists