Abstract
BACKGROUND: Deciding on intravenous thrombolysis (IVT) in acute ischemic stroke (AIS) patients with reported recent direct oral anticoagulant (DOAC) intake remains challenging due to concerns about hemorrhagic risk and the absence of randomized controlled trial evidence. This study aimed to provide a comprehensive characterization of all AIS patients with reported recent DOAC intake-regardless of IVT eligibility-treated at a comprehensive stroke center that routinely measures calibrated anti-facor IIa/Xa activity at admission. METHODS: In this retrospective study, clinical and procedural data from AIS patients with recent DOAC intake and calibrated anti-factor IIa/Xa activity measured within three hours of admission were analyzed. Patients were treated at the University Hospital Essen between March 2017 and October 2023. RESULTS: Among 469 included patients, anti-factor IIa/Xa activity was ≤ 30 ng/ml in 28%, > 30- ≤ 50 ng/ml in 9%, > 50- ≤ 75 ng/ml in 9%, > 75- ≤ 100 ng/ml in 9% and > 100 ng/ml in 45%. Lower DOAC levels correlated with severe stroke symptoms at admission (ρ = - 0.263, p < 0.001). IVT was administered to 33.5% of patients with DOAC levels ≤ 50 ng/ml, compared to only 4% among those with levels > 50 ng/ml, the majority of whom received prior reversal with idarucizumab. Symptomatic intracranial haemorrhage (sICH) occurred in 4% of IVT-treated and 1% of non-IVT-treated patients, without association to anticoagulation status. CONCLUSIONS: A considerable proportion of AIS patients with recent DOAC intake exhibited minimal or no anticoagulant activity at presentation. Those with the lowest levels also showed highest stroke severity. IVT was safe across all DOAC level groups, with low and comparable sICH rates. These findings support the rationale for a randomized trial evaluating IVT without prior DOAC level testing.