Abstract 4144096: Outcomes of Left Atrial Appendage Occlusion in Patients with Atrial Fibrillation and Gastrointestinal Bleeding: Insights from a Multicenter Registry

Background: The patient population undergoing left atrial appendage occlusion (LAAO) in the US is older and at a higher bleeding and thromboembolic risk than that enrolled in the initial trials that led to FDA approval. Real world outcomes in this population have implications for the use of LAAO. Goals: We sought to compare clinical outcomes of LAAO in patients with atrial fibrillation (AF) with prior major gastrointestinal (GI) bleeding to continued oral anticoagulation (OAC). Methods: Using data from a large US hospital system, patients with AF who underwent LAAO from 01/2016 to 11/2022 with a history of at least one major (requiring admission or transfusion) GI bleed event (LAAO group) were identified and compared to a control group with prior GI bleed with continued OAC. Controls were selected in a 1:2 fashion using propensity score matching based on 17 variables. Hospital admissions for major bleeding, ischemic stroke or transient ischemic attack (TIA) as well as survival were tracked during follow-up. Results: Patients in the LAAO group (n=642, age 76.5±8.2 years, 47.8% female) had higher CHA 2 D 2 -VASc (4.3±1.7 vs. 4.1±1.6, p=0.003) and lower HAS-BLED (3±0.9 vs. 3.3±0.9, p<0.001) scores than the control group (n=1273, age 76.3±10.1 years, 47.8% female) but were otherwise comparable. At baseline, a higher proportion of patients in the LAAO group was on a direct oral anticoagulant (59.7% vs. 44.9%, p<0.001), while fewer patients were on warfarin (15.9% vs. 53.3%, p<0.001). Over a median follow-up of 2.95 (1.53-4.89) years, patients in the LAAO group had lower rates of a major bleeding event (97.8 vs. 140 events per 1,000 person-years, p<0.001) as compared to the control group. Similarly, fewer patients in the LAAO group were admitted for ischemic stroke or TIA (15.4 vs. 26.1 events per 1,000 person-years, p=0.016) when compared to the control group. Finally, survival rates in the LAAO group were improved as compared with the control group (89.4 vs. 119.9 events per 1,000 person-years, p<0.001), Figure 1. Conclusions: In patients with prior major GI bleeding, LAAO is associated with superior clinical outcomes with lower bleeding and stroke rates when compared to OAC.