TIA triage in emergency department using acute MRI (TIA-TEAM): a feasibility and safety study

Positive diffusion weighted imaging (DWI) on MRI is associated with increased recurrent stroke risk in TIA patients. Acute MRI aids in TIA risk stratification and diagnosis.

To evaluate the feasibility and safety of TIA triage directly from the emergency department (ED) with acute MRI and neurological consultation.

Consecutive ED TIA patients assessed by a neurologist underwent acute MRI/MRA of head/neck per protocol and were hospitalized if positive DWI, symptomatic vessel stenosis, or per clinical judgment. Stroke neurologist adjudicated the final TIA diagnosis as definite, possible, or not a cerebrovascular event. Stroke recurrence rates were calculated at 7, 90, 365 days and compared with predicted stroke rates derived from historical DWI and ABCD(2) score data.

One hundred twenty-nine enrolled patients had a mean age of 69 years (± 17) and median ABCD(2) score of 3 (interquartile range [IQR] 3-4). During triage, 112 (87%) patients underwent acute MRI after a median of 16 h (IQR 10-23) from symptom onset. No patients experienced a recurrent event before imaging. Twenty-four (21%) had positive DWI and 8 (7%) had symptomatic vessel stenosis. Of the total cohort, 83 (64%) were discharged and 46 (36%) were hospitalized. By one-year follow-up, one patient in each group had experienced a stroke. Of 92 patients with MRI and index cerebrovascular event, recurrent stroke rates were 1.1% at 7 and 90 days. These were similar to predicted recurrence rates.

TIA triage in the ED using a protocol with neurological consultation and acute MRI is feasible and safe. The majority of patients were discharged without hospitalization and rates of recurrent stroke were not higher than predicted.