Tissue-Based Definition of TIA Is Superior to Time-Based Definition for Predicting Recurrent Stroke

The American Stroke Association has recommended changing the criteria for defining transient ischemic attack (TIA) from time-based to tissue-based (infarction identified on diffusion-weighted magnetic resonance imaging [DWI]). In an international observational study, researchers compared the prognostic accuracy of the two definitions of TIA for predicting recurrent stroke at 7 and 90 days in 4574 patients with TIA defined by time-based criteria. Recurrent stroke was defined as “a new neurologic deficit of vascular origin which lasted more than 24 hours or led to death and occurred after complete resolution of the inception TIA.”

Among 3206 patients who were imaged with DWI, infarction was identified in 884 (tissue-positive cases). In the DWI…