The impact of atrial fibrillation (AF) on outcomes of mechanical thrombectomy (MT) for acute ischemic stroke (AIS) is controversial, and with a paucity of evidence base. This study aimed to investigate the potential association between AF and outcomes after MT in AIS patients. A post-hoc analysis of a multi-center prospective clinical trial was conducted. Before and after propensity score matching (PSM), the clinical features were compared between patients with and without AF. Multivariable logistic regression and mediation analyses were performed to assess the relationship between AF and ICH. Of the total 245 patients, 123 patients were included in the AF group. After PSM, the AF group showed more retrieval attempts (P = 0.004), comparable favorable outcome (P = 0.493), and mortality (P = 0.362) at 90 days. Multivariate analysis revealed that AF was significantly associated with increased risk for ICH (OR 2.198; 95%CI 1.099-4.395; P = 0.026). INR and retrieval attempts were found to act as partial mediations. In the subgroup with lower INR, AF still had a significant association with ICH (OR 2.496; 95%CI 1.331-4.679; P = 0.004). In AIS patients undergoing MT, AF was associated with more retrieval attempts and higher risk of any ICH. Of note, the effect of AF on the increased risk of ICH was partly attributable to the adjusted anticoagulation status and more retrieval attempts. It is crucial to elaborately prevent ICH after thrombectomy for stroke patients with AF.
Keywords: Atrial fibrillation; Intracranial hemorrhage; Ischemic stroke; Mechanical thrombectomy.