Abstract W P36: Immediate Changes in Stroke Lesion Volumes Following Thrombolysis Predict Both Imaging and Clinical Outcomes
Objectives and Hypotheses: Our objective was to quantify the DWI and MTT changes at 2 and 24 hours after IV-tPA and evaluate the effect of reperfusion and DWI change on immediate neurological improvement and clinical outcome using the latest available mRS up to 90 days.
Methods: Patients were selected from the Lesion Evolution in Stroke and Ischemia On Neuroimaging (LESION) Project if they had a baseline MRI with evaluable DWI and PWI, were treated with standard IV-tPA, had post-treatment MRI at 2 or 24 hours and FLAIR at follow-up. A reader measured the DWI, MTT and FLAIR volumes using a validated technique. A vascular neurologist scored the NIHSS at pre-treatment, 2 and 24 hours and the mRS at discharge, 5, 30 and 90 days.
Results: Seventy-one patients met the study criteria with mean (±SD) age of 71.6 (±16.4) years, 58% women, median baseline NIHSS 9 (IQR: 4-18), median onset to triage 45 minutes (30-65) and median first MRI to IV-tPA 47 minutes (39-59). For the 43 patients with baseline DWI ≥ 5 ml, 60% of patients with a decrease at 2 hours had a favorable outcome versus 18% of no decrease (p=0.014). There was also a significant difference in mRS distribution between groups, (0-3 versus 2-6, p=0.008). Using linear regression, the 2 hour DWI (p=0.037), change in 2 hour DWI (p<0.000) and change in 24 hour NIHSS (p=0.041) but not the 2 hour NIHSS or its change were predictive of follow-up FLAIR volume. For the 53 patients with a baseline MTT ≥ 5 ml, 42 patients (79%) had a decrease in MTT > 7 ml and 11 (21%) had an increase or no change (p<0.0001) at 24 hours. The latest available mRS was 0-1 in 45% of the patients with a MTT decrease and in 0% of the patients with no decrease (p=0.002). There was also a significant difference in mRS distribution between these groups, (0-5 versus 4-5, p=0.020). Using linear regression, age (p=0.040), admit NIHSS (p<0.000) and change in 24 hour NIHSS (p=0.002) were predictive of mRS distribution.
Conclusions: In patients with a substantial baseline DWI lesion, the decrease of DWI volume at 2 hours post-thrombolysis is a significant predictor of good imaging and clinical outcomes. In patients with a substantial baseline MTT lesion, the decrease of NIHSS and MTT volume at 24 hours post-thrombolysis are significant predictors of good imaging and clinical outcomes.
Author Disclosures: M. Luby: None. S.J. Warach: None. J.G. Merino: None.
- © 2014 by American Heart Association, Inc.