Abstract 3267: Persistence of Hyperdense Middle Cerebral Artery Sign on Follow-up CT Scan is Associated with Poor Outcome in Ischemic Stroke Patients Treated with Intravenous Thrombolysis

Abstract

Background- Early identification of reliable predictors of functional outcomes is important for planning rehabilitation strategies in patients with acute ischemic stroke (AIS). Hyperdense middle cerebral artery sign (HMCAS) on unenhanced computerized tomography (CT) of the brain represents presence of thrombus, often associated with poor outcome at 3-months. In thrombolyzed cases, HMCAS may disappear or persist on the follow-up CT scan. We evaluated whether persistence of HMCAS on follow-up CT predicts functional outcome at 3-months. Methods- Consecutive AIS patients treated with intravenous thrombolysis between 2007 and 2010 were included. HMCAS was assessed on admission as well as follow-up CT by 2 independent readers, blinded to patient data and outcomes. Data were analyzed for early predictors of poor functional outcome at 3months (modified Rankin scale 2-6points). Results- Of the total of 2238 patients admitted during the study period, 226 (10.1%) with anterior circulation AIS treated with intravenous thrombolysis were included. Median age of the IV-TPA treated patients was 65yrs (range 19-92), 63% males and median National Institute of Health Stroke Scale (NIHSS) 16points (range 4-32). HMCAS was observed on admission CT scan in 109 (48.2%) patients and persisted on follow-up CT in 52 (47.7%) of them. Overall, 108 (47.8%) patients achieved poor functional outcome at 3-months. Older age (OR 1.024;95%CI0.999-1.048), admission NIHSS score (OR1.08;95%CI 1.03-1.14,p=0.002) and HMCAS on follow-up CT scan (OR 10.25;95%CI 4.05-25.99,p <0.0001) were associated with poor outcome at 3-months. Conclusion- Persistence of HMCAS on the follow up CT scan in AIS patients receiving intravenous thrombolysis is an early predictor of poor functional outcome at 3-months.