Higher risk of further vascular events among transient ischemic attack patients with diffusion-weighted imaging acute ischemic lesions

Background and Purpose - Recently, a new definition of transient ischemic attack (TIA) has been proposed based on the duration of symptoms and diffusion-weighted imaging (DWI) findings. We investigate the value of temporal and neuroimaging data on the prognoses of TIA patients. Methods - Clinical data, symptom duration, DWI, and ultrasonographic findings were collected in 83 consecutive classical TIA patients attended in the emergency department. Stroke recurrence, myocardial infarction, or any vascular event was recorded at follow-up ( mean of 389 days). Results - A total of 27 (32.5%) patients revealed focal abnormalities on DWI, whereas 37(44.6%) had symptoms lasting >1 hour. Large-artery disease was detected in 37 ( 44.6%) patients. Twenty (24.1%) patients experienced an endpoint: 2 (2.4%) myocardial infarctions, 16 (19.3%) cerebral ischemic events, and 2 cases ( 2.4%) of peripheral arterial disease. Cox proportional hazards multivariate analyses identified the association of symptoms >1 hour with DWI abnormalities as independent predictors of further cerebral ischemic events or any vascular event ( hazard ratio [ HR], 5.02; CI, 1.37 to 18.30; P = 0.015; and HR, 3.77; CI, 1.09 to 13.00; P = 0.029). Large-artery occlusive disease also remained an independent predictor of both endpoints ( HR, 4.22; CI, 1.17 to 15.22; P = 0.028; and HR, 3.60; CI, 1.14 to 11.39; P = 0.0293). Conclusions - TIA patients with DWI abnormalities associated with duration of symptoms >1 hour and those with large-artery occlusive disease have a higher risk of further vascular events. Routine use of DWI and Doppler ultrasonographic examinations will be useful for identifying TIA patients at high risk to plan aggressive prevention therapies.