Revascularization outcomes following acute ischemic stroke in patients taking direct oral anticoagulants: a single hospital cohort study

Successful revascularization therapy is of paramount importance in patients suffering acute ischemic stroke (AIS). However, there is currently only limited evidence on revascularization outcomes for patients suffering AIS while treated with direct oral anticoagulants (DOACs). The aim of our study was to determine the efficacy and safety of intravenous thrombolysis (IVT) and mechanical reperfusion (MeR) in AIS patients taking DOACs, and compare them to randomized clinical trials (RCTs), which included patients without DOAC treatment. In an observational cohort study, we analyzed clinical and radiological outcomes following AIS for all consecutive patients on DOAC therapy treated by IVT or MeR, between 2013 and 2019, at the University Medical Center Ljubljana. Patients in the IVT group were on dabigatran treatment and have received idarucizumab as a reversal agent prior to IVT. Patients in the MeR group had a large vessel occlusion. The primary outcome of the study was efficiency, defined as significant improvement after recanalization (National Institutes of Health Stroke Scale (NIHSS) score improvement of ≥8 points after 24 h and modified Rankin Scale (mRS) ≤2 after 3 months) and safety, defined as occurrence of symptomatic intracerebral hemorrhage (SICH) and mortality. Fifty-one DOAC-treated patients with AIS were included. Nineteen dabigatran-treated patients received IVT after reversal by idarucizumab. Thirty-two patients with a large vessel occlusion (12 on dabigatran, 12 on rivaroxaban, and 8 on apixaban) received MeR. Median NIHSS at admission was 9 in the IVT group and 17 in the MeR group. A significant clinical improvement, 24 h after revascularization (median improvement of NIHSS ≥8), occurred in 84% of patients treated with IVT and 25% of patients treated with MeR. A favorable functional outcome after 3 months (modified Rankin Scale (mRS) ≤2) occurred in 84 % of patients treated with IVT and 44% of patients treated with MeR. SICH occurred in one patient (5%) in the IVT group, and in two patients (6%) in the MeR group. In summary, in our observational study of DOAC-treated AIS patients, the level of IVT efficiency was substantially better than in the RCTs. At the same time, the results of MeR treatment were on the same level as in non-DOAC AIS patients included in the RCTs. The observed safety of IVT and MeR treatment was similar to the RCTs. We propose that thrombi in patients on dabigatran may have increased susceptibility to IVT, thereby allowing for better clinical results.