Evaluation of a CTA-Triage Based Transient Ischemic Attack Service: A Retrospective Single Center Cohort Study

We designed a computed tomography angiography (CTA)-based algorithm for patients presenting to hospital with a transient ischemic attack (TIA) which identified high-risk patients, as well as inpatient versus semiurgent outpatient management following MRI, and we hypothesised that this would be effective.

Patients seen in the ED at the Royal Adelaide Hospital from March 3, 2012 to November 30, 2016 with TIA-like symptoms were assessed for a cardioembolic source (clinical assessment, electrocardiogram) and underwent intra and extracranial CTA. Patients with a referable >50% stenosis were admitted and given dual antiplatelets. Most high-risk cardiac source patients were also admitted and anticoagulated. Other patients were loaded with aspirin, or changed to clopidogrel if on aspirin, and reviewed as outpatients following semiurgent MRI (3-4 days). We assessed the 90-day recurrent stroke risk in this cohort as a whole, and in those with a final cerebrovascular diagnosis.

1167 patients were diagnosed in Emergency as TIA and referred via our algorithm. A total of 150 were admitted, 78 had "high-risk" features. A total of 1017 patients were reviewed in the TIA clinic. The average age of the total cohort was 65.8 years old. Final diagnosis was TIA/minor stroke in 69% admitted patients and 30% clinic patients (P value < .0001). The 90-day recurrent stroke risk in these patients was 2.0% (5.8% admitted vs .7% clinic patients, P value < .0001). In those with noncerebrovascular diagnoses, there were no recurrent strokes within 90 days.

Stroke risk is very low using CTA guided semiurgent clinic review algorithm.