Impact of prior antithrombotic therapy on safety and outcomes of endovascular therapy in large-core acute ischemic stroke

Background and purpose: Evidence on whether prior antithrombotic drug (ATD) use affects outcomes after endovascular therapy (EVT) is limited in patients with large-core acute ischemic stroke. Materials and methods: This was a subanalysis of the Recovery by Endovascular Salvage for Cerebral Ultra-acute Embolism–Japan Large Ischemic Core Trial, which assessed the efficacy of EVT in patients with large-vessel occlusion and extensive early ischemic changes. The primary outcome was a modified Rankin Scale (mRS) score of 0–3 at 90 days. Secondary outcomes included intracerebral hemorrhage (ICH) within 48 hours, symptomatic ICH, 90-day mortality, ordinal mRS shift, and ≥8-point improvement in National Institutes of Health Stroke Scale score at 48 hours. Logistic regression models were used to assess treatment effects and interactions between ATD and EVT. Results: A total of 202 patients were included (ATD, n = 70; no ATD, n = 132). There was no significant interaction between use of ATD and the effect of EVT in terms of the primary outcome (pinteraction=0.944) or secondary outcomes (pinteraction=0.218–0.752). In the EVT cohort, prior ATD use was not associated with the primary outcome (adjusted OR 1.16, 95% CI 0.41–3.23). Results were consistent for antiplatelet drugs (adjusted OR 0.70, 95% CI 0.18–2.71) and anticoagulants (adjusted OR 1.52, 95% CI 0.45–5.20). Conclusions: In this exploratory subanalysis, prior ATD use did not significantly modify the observed treatment effect of EVT in patients with large-core acute ischemic stroke. These findings suggest that prior ATD use alone should not preclude consideration of EVT.