ABSTRACT NUMBER: ESOC2026A987 LONG-TERM IMAGING FINDINGS AND OUTCOMES AFTER TRANSIENT ISCHEMIC ATTACK

Abstract Background and aims Transient ischemic attack (TIA) carries a high short-term risk of acute ischemic stroke (AIS). Early identification of patients at increased risk is crucial for effective secondary prevention. However, the clinical value of systematic follow-up neuroimaging after TIA remains uncertain, as standardized imaging protocols are lacking and covert brain infarcts may remain undetected. We investigated the frequency and clinical relevance of new cerebral ischemia identified on follow-up imaging after TIA. Methods We conducted a retrospective cohort study of consecutive patients evaluated for probable TIA at a comprehensive Stroke Center between 2015 and 2019. Follow-up imaging was performed at the discretion of treating physicians. The primary outcome was new cerebral ischemia, defined as symptomatic AIS or covert brain infarction detected on follow-up imaging. Associations between baseline characteristics and ischemic events were assessed using multivariable Cox regression, and long-term mortality was analyzed according to ischemia type. Results Among 1,359 patients with probable TIA, 244 (median age 73 years; 35% female) underwent follow-up imaging. New cerebral ischemia was detected in 19% (46/244), including 80% symptomatic AIS and 20% covert brain infarcts. New ischemia was independently associated with higher ABCD2 scores, symptomatic baseline stenosis, and smoking history. Patients with covert infarcts had vascular risk profiles similar to those with symptomatic AIS but were younger. Long-term mortality did not differ between groups. Conclusions Follow-up imaging after TIA frequently reveals clinically relevant ischemia, including covert infarction, and may support improved risk stratification and individualized secondary prevention strategies. Conflict of interest noting to disclose