Effect of prior antiplatelet therapy on large vessel occlusion in patients with non-valvular atrial fibrillation newly initiated on apixaban

Introduction We evaluated the effect of prior antiplatelet therapy on large vessel occlusion (LVO) in patients with non-valvular atrial fibrillation (NVAF) newly initiated on apixaban. Methods Patients with acute LVO with acute stroke due to NVAF or stenosis with NVAF started on apixaban within 14 days of onset were enrolled. We compared incidence of major bleeding, cerebral hemorrhage, ischemic events, cerebral infarction, and all-cause mortality between patients with and without prior antiplatelet therapy for acute LVO. We also compared these events between patients who continued antiplatelet therapy after onset (continued group) and those who discontinued it (discontinued group). Hazard ratios were estimated after adjusting for confounders; interaction was evaluated considering intravenous thrombolysis (IVT) or endovascular treatment (EVT) according to major bleeding. Results The study comprised 686 eligible patients (excluded [n = 194]; enrolled [n = 492]). The antiplatelet group consisted of older patients (mean: 79 vs. 76 years; p = 0.006) and had a higher cumulative incidence of major bleeding (7.3% vs. 2.9%, p = 0.003). The incidence of ischemic events and all-cause mortality was similar between the groups. Among the 109 patients in the antiplatelet group, the cumulative incidence of major bleeding, ischemic events, and all-cause mortality was comparable between continued group (n = 26) and discontinued group (n = 83). There were no significant differences between groups with and without IVT/EVT. However, major bleeding occured more frequently in the antiplatelet group without IVT. Conclusion Prior antiplatelet therapy for LVO in patients with NVAF newly initiated on apixaban was associated with major bleeding, which was more frequent in the antiplatelet group without IVT.