Abstract 4347966: High Use of P2Y12 Inhibitors and DOACs Persists up to One Year After Percutaneous Left Atrial Appendage Occlusion

Background: Percutaneous left atrial appendage occlusion (pLAAO) is used as an alternative to anticoagulation in patients with atrial fibrillation. Long-term patterns of antiplatelets and anticoagulants use post pLAAO compared to direct oral anticoagulants (DOACs) users are unknown. Hypothesis: We hypothesized that the use of antiplatelets and anticoagulants remains prevalent up to one year following pLAAO. Methods: We emulated a target trial where patients with atrial fibrillation were randomly assigned to receive pLAAO or DOACs in the 1:3 ratio using a nationally representative 15% sample of Medicare beneficiaries from Jan 2015 to Dec 2020. We reported the number of patients who received related treatment (>=1 prescription) in the certain time range. We assessed the following drugs up to one year post pLAAO implantation: Antiplatelets (clopidogrel, ticagrelor, prasugrel), 2- vitamin K antagonists (warfarin) and 3- DOACs (apixaban, dabigatran, rivaroxaban, edoxaban). Results: Among 3,692 patients who underwent pLAAO, use of DOACs and warfarin decreased substantially by 6-12 months post pLAAO (from 47.0% to 7.4% and from 42.4% to 2.2%, respectively). In the DOACs arm which had 11,076 patients, use of DOACs remained high on follow up (81.0% at 1-year). At 6-12 months post index date, patients who received pLAAO were significantly less likely to remain on DOACs (7.4% vs. 81.0%; p< 0.001) or warfarin (2.2% vs 4.6%; p < 0.001), but more likely to be on a P2Y12 inhibitor (55.0% vs 9.2%; p < 0.001), table 1. Conclusion: The use of P2Y12 inhibitors and DOACs remained high at 6-12 months post pLAAO with approximately 1 in 2 patients receiving a prescription for a P2Y12 inhibitor and 1 in 14 receiving a prescription for a DOAC. These high prescribing patterns warrant further investigation as they may be contributing to an increased bleeding risk post pLAAO.