Antithrombotic Treatment After Left Atrial Appendage Occlusion in Older Atrial Fibrillation Patients

Abstract Left atrial appendage occlusion (LAAO) is an alternative to oral anticoagulants (OAC) for stroke prevention in nonvalvular atrial fibrillation (NVAF); however, real-world data on adherence to its postprocedural treatment protocol remain limited. We evaluated post-LAAO antithrombotic treatment patterns in a cohort of 16304 NVAF patients (mean [SD] age = 78 [6]; 47% female; CHA2DS2-VASc score = 5.0 [1.5]) undergoing first-time LAAO using Optum claims data 2015-2024. OAC discontinuation was defined as a ≥ 60-day gap in supply, and prolonged OAC use was operationally defined as either (1) an OAC refill following a TEE performed 30–90 days post-implantation or (2) OAC refill beyond 90 days post-implantation, regardless of TEE completion. Among LAAO recipients, 9844 (60%) received concomitant OAC and 3499 (10%) received P2Y12 inhibitor at implantation. Transesophageal echocardiography (TEE) was performed in 11237 (69%) patients at 45 (±15) days. Among OAC users (n = 9844), 30% and 85% discontinued OAC by 45 days and 6 months post-implantation, respectively; only 23% patients followed the standard postprocedural protocol. Common deviation from the protocol included no TEE at 45 (±15) days (30%), early OAC discontinued (22%), continued OAC use post-TEE (10%), and P2Y12 inhibitor initiated early or not initiated (10%). Prolonged OAC use was observed in 1970 patients. Factors associated with a higher likelihood of prolonged OAC use included older age, Black race, cardio ablation, and a longer duration of prior OAC use. These findings suggest moderate to low adherence to the LAAO postprocedural protocol, warranting further evaluation of the clinical impact of these adherence patterns.