Intravenous Thrombolysis 4.5-9 Hours After Stroke Onset - a Cohort Study from the TRISP Collaboration.

Abstract

To investigate the safety and effectiveness of intravenous thrombolysis (IVT) >4.5-9 hours after stroke onset and the relevance of advanced neuroimaging for patient selection. Prospective multicenter cohort study from the ThRombolysis in Ischemic Stroke Patients (TRISP) collaboration. Outcomes were symptomatic intracranial hemorrhage (sICH), poor 3-month functional outcome (mRS 3-6) and mortality. We compared (i) IVT >4.5-9 hours versus 0-4.5 hours after stroke onset and (ii) within the >4.5-9 hours-group baseline advanced neuroimaging (CT perfusion, MR perfusion or MR DWI/FLAIR) versus non-advanced neuroimaging. Of 15'827 patients, 663 (4.2%) received IVT >4.5-9 hours and 15'164 (95.8%) within 4.5 hours after stroke onset. The main baseline characteristics were evenly distributed between both groups. Time of stroke onset was known in 74.9% of patients treated between >4.5-9 hours. Using propensity score weighted binary logistic regression analysis (OTT >4.5-9 hours vs. OTT 0-4.5 hours), the probability of sICH (ORadjusted 0.80[0.53-1.17]), poor functional outcome (ORadjusted 1.01[0.83-1.22]) and mortality (ORadjusted 0.80[0.61-1.04]) did not differ significantly between both groups. In patients treated between >4.5-9 hours, the use of advanced neuroimaging was associated with a 50% lower mortality compared to non-advanced imaging only (9.9% vs 19.7%; ORadjusted 0.51[0.33-0.79]). This study showed no evidence in difference of sICH, poor outcome and mortality in selected stroke patients treated with IVT between >4.5-9 hours after stroke onset compared to those treated within 4.5 hours. Advanced neuroimaging for patient selection was associated with lower mortality. This article is protected by copyright. All rights reserved.