Abstract TP25: Early Major Neurologic Improvement after Endovascular Therapy in Acute Ischemic Stroke

Abstract

Background and Purpose: Intravenous thrombolysis is associated with early major neurologic improvement, which is reported to occur in about a quarter of patients after 24 hrs. The aim of the study is to evaluate the frequency and predictors of early major improvement in patient with ischemic stroke after undergoing acute intra-arterial therapy. Materials and methods: Prospective collected database of patients undergoing intra-arterial therapy for the acute ischemic stroke from January 2008 to December 2011 was reviewed. The NIHSS was used to assess severity of stroke in patients upon admission, 24 hrs after procedure and at hospital discharge. Major neurological improvement was defined as improvement of NIHSS by more or equal to 8 or absolute NIHSS of 0 or 1. Arterial recanalization was defined as thrombolysis in cerebral infarction grade 2b or 3. Favorable outcome was defined as modified Rankin scale of 0-2 at 1 month and 3 months. Demographic and radiographic data were collected. Results: MNI was seen in 28 out of 138 (20%) of patients at 24 hours but was not associated with a 30 day or 90 day favorable outcome. MNI at discharge was seen in 47 of 148 (31%) patients and was associated with a 30 day and 90 day favorable outcomes of 0-2 on mRankin (Odds Ratio (OR) : 9.1, 95% confidence interval (CI): 3.7-22.5). Recanalization was associated with MNI at 24 hours (OR 3.1, 95% CI: 1.2-7.9) and MNI at discharge (OR 2.8, 95% CI: 1.3-6.0). Among pre-treatment variables, MNI at discharge was associated with imaging by pre-treatment Alberta Stroke Program Early CT Score (median 9 with MNI, 8 without MNI, p=0.03) and time to treatment (median 5.2 hours with MNI v 7.2 hours without MNI, p<0.01). Age and baseline NIHSS were not associated with MNI. In a logistic regression model, favorable outcome at 90 days was independently associated with baseline NIHSS and MNI at discharge. Conclusions: MNI after intra-arterial therapy was seen in about a quarter of patients and was associated with higher CT ASPECT scores, time to therapy, and arterial recanalization. MNI at discharge was an independent predictor of long term outcome.