AUTHOR=Galinovic Ivana , Boutitie Florent , Fiebach Jochen B. , Villringer Kersten , Cheng Bastian , Ebinger Martin , Endres Matthias , Fiehler Jens , Ford Ian , Thijs Vincent , Lemmens Robin , Muir Keith W. , Nighoghossian Norbert , Pedraza Salvador , Simonsen Claus Z. , Roy Pascal , Gerloff Christian , Thomalla Götz TITLE=Post-hoc Analysis of Outcome of Intravenous Thrombolysis in Infarcts of Infratentorial Localization in the WAKE-UP Trial JOURNAL=Frontiers in Neurology VOLUME=10 YEAR=2019 URL=https://www.frontiersin.org/journals/neurology/articles/10.3389/fneur.2019.00983 DOI=10.3389/fneur.2019.00983 ISSN=1664-2295 ABSTRACT=

Introduction: In WAKE-UP (Efficacy and Safety of MRI-based Thrombolysis in Wake-Up Stroke), patients with an acute stroke of unknown onset time were randomized to treatment with intravenous alteplase or placebo, guided by MRI.

Methods: In this exploratory post-hoc secondary analysis we compared clinical and imaging data, as well as treatment effects and safety of intravenous thrombolysis between patients with infra- vs. supratentorial stroke.

Results: Forty-eight out of 503 randomized patients (9.5%) presented with a stroke involving the cerebellum or brainstem. Patients with infratentorial stroke were younger compared to patients with supratentorial stroke (mean age 60 vs. 66 years), more frequently male (85 vs. 62%), and less severely affected (median NIHSS 4.5 vs. 6.0). There was no heterogeneity for treatment effect between supratentorial (OR 1.67 95% CI 1.11–2.51) and infratentorial (OR 1.31 95% CI 0.41–4.22) sub-groups (test for interaction p = 0.70). In patients with infratentorial stroke, favorable outcome [a score of 0–1 on the modified Rankin scale (mRS) at 90 days] was observed in 12/22 patients (54.5%) in the alteplase group and in 13/25 patients (52.0%) in the placebo group (p = 0.59). The primary safety endpoint (death or mRS 4–6 at day 90) occurred in three patients of the alteplase group (13.6%) and three patients in the placebo group (12.0%); p = 0.74.

Discussion: WAKE-UP was underpowered for demonstrating treatment effect in subgroup analyses however, based on our current results, there is no evidence to recommend withholding MRI-guided thrombolysis in patients with unknown onset stroke of infratentorial localization.