Yield of systematic transcranial doppler in patients with transient ischemic attack

Abstract

Urgent evaluation and treatment of transient ischemic attack (TIA) patients in a dedicated TIA clinic may reduce the 90-day stroke risk by 80%. ABCD2 (Age, Blood pressure, Clinical features, Duration, Diabetes) score and magnetic resonance imaging abnormalities help to identify patients at high risk of stroke. Our aim was to determine whether the use of transcranial Doppler (TCD) examination on arrival at the TIA clinic yields additional information that facilitates the identification of patients at high risk of stroke recurrence. Between January 2003 and December 2007, 1,881 patients were admitted to SOS-TIA clinic (a TIA clinic with around-the-clock access). Clinical and vascular assessment included TCD performed by a neurologist immediately after admission. Stroke prevention measures were initiated on arrival, in accordance with guidelines. All patients were followed for 1 year after presentation to the SOS-TIA clinic. A total of 1,823 TCD examinations were performed within 4 hours of admission. Intracranial narrowing or occlusion was found in 8.8% of patients, and was independently associated with age, hypertension, and diabetes. After 1-year follow-up on best preventive therapy, the incidence of recurrent vascular events (intracranial revascularization for TIA recurrence, stroke, myocardial infarction, and vascular death combined) was 7.0% in patients with intracranial narrowing or occlusion and 2.4% in those without (log-rank, p = 0.007). The hazard ratio of combined outcome for the presence of intracranial narrowing or occlusion was 2.29 (95% confidence interval [CI], 1.15-4.56; p = 0.02) in multivariate analysis including age, gender, hypertension, and diabetes, and was 2.50 (95%CI, 1.24-5.05; p = 0.01) in multivariate analysis including ABCD2 score > or =4. Immediate TCD examination on arrival at the TIA clinic is feasible and could help to identify patients at high risk of vascular events recurrence. This study supports a systematic intracranial vascular examination in the initial management of TIA.