Prediction of hemorrhagic transformation in patients with mild atrial fibrillation-associated stroke treated with early anticoagulation: post hoc analysis of the Triple AXEL Trial

Objectives: To investigate the predictors of hemorrhagic transformation (HT) in patients with mild atrial fibrillation-related stroke who were treated with early anticoagulation. We conducted a post-hoc subgroup analysis from Acute Cerebral Infarction Patients with Non-valvular Atrial Fibrillation (Triple AXEL) study. Patients and methods: The Triple AXEL study was a randomized, multicenter, open-label, blinded end-point evaluation, comparative phase 2 trial. To identify the relationship between the type of HT and risk factors. We analyzed various factors using data from the Triple AXEL study, such as sex, history of hypertension, diabetes, microbleeds, concomitant antiplatelet use, initial infarction volume, initial infarction location, and new intracranial hemorrhage on follow-up gradient recalled echo or susceptibility-weighted imaging. Results: We analyzed various factors by dividing patients into a new HT group and a no HT group. No correlation was found between HT and risk factors that were significantly associated with HT, including age, sex, history of hypertension, diabetes, microbleeds, concomitant antiplatelet use, and initial infarction volume. When the initial infarction was classified into anterior circulation infarction (ACI) and posterior circulation infarction (PCI), the occurrence of new HT was significantly more associated with PCI than with ACI (57.6% vs 24.0%, P = 0.001). Multivariate logistic regression analysis was performed using HT as a response variable. Only the location of initial infarction according to the vascular territory contributed to the increased risk of HT (OR2.3, 95%CI1.33-3.91, P = 0.003). Conclusion: PCI is a very important independent risk factor for HT in patients with mild AF-related stroke treated with early anticoagulation.