Abstract WP132: Contemporary U.S. Practice Patterns Regarding Anticoagulation and LAA Closure in ICH Survivors with Atrial Fibrillation

Introduction: Optimal secondary stroke prevention strategies remain uncertain for patients with atrial fibrillation (AF) who experience intracerebral hemorrhage (ICH). Anticoagulation reduces the risk of ischemic stroke in AF patients but generally increases the risk of hemorrhagic stroke. Left atrial appendage (LAA) occlusion is emerging as an alternative for stroke prevention in AF, though few data exist on outcomes in ICH patients. In this context, little is known about contemporary U.S. practice patterns regarding secondary stroke prevention in patients with AF and ICH. Methods: We performed a retrospective cohort study using linked electronic health record, pharmacy, and insurance claims data on >11 million patients at 29 healthcare organizations across the U.S. Validated ICD-10 diagnosis codes were used to identify adults with AF who were hospitalized during 2016-2024 for ICH. We used RxNorm codes to identify prescriptions for aspirin and anticoagulant drugs, specifically warfarin, apixaban, dabigatran, or rivaroxaban. LAA occlusion was defined using validated CPT codes. Survival statistics were used to calculate cumulative rates starting at hospital discharge and censoring at the time of death or end of linked claims data. Results: We identified 2,361 AF patients hospitalized with ICH. Their mean age was 65.4 years, 40.5% were female, the median NIHSS score was 9 (IQR, 3-18), 26.9% were receiving anticoagulation prior to their ICH, and about half were discharged home or to an acute rehabilitation facility (Table). Cumulative 5-year rates were 60.4% (95% CI, 56.4-64.5%) for anticoagulation with or without concomitant aspirin, 43.4% (95% CI, 38.2-49.1%) for aspirin only, and 4.4% (95% CI, 2.6-7.5%) for LAA occlusion with or without concomitant anticoagulation and/or aspirin (Figure 1). LAA occlusion rates did not differ by index ICH date ( P = 0.91) (Figure 2). Conclusions: In this large, contemporary national U.S. cohort of patients with AF and ICH, approximately half were started on anticoagulation after discharge, and the remainder were mostly treated with aspirin only. Fewer than 1 in 20 patients underwent LAA occlusion, even in recent years. These findings suggest ongoing uncertainty and equipoise between anticoagulant and antiplatelet therapy for secondary stroke prevention in patients with AF and ICH. This substantial variation underscores the need for data from randomized trials to guide secondary stroke prevention in this high-risk population.