Abstract 4342658: Sub-optimal guideline-concordant anticoagulation after atrial fibrillation ablation

Introduction: Catheter ablation (CA) is a treatment strategy for patients with atrial fibrillation (AF). The 2023 ACC/AHA/ACCP/HRS guidelines recommend oral anticoagulant (OAC) therapy for at least 3 months post-CA with long-term continuation based on individual stroke risk. Research Question: Are US patients with AF after CA treated with guideline-concordant anticoagulation? Methods: The Optum Clinformatics DataMart Date of Death claims data were used for this study, which included patients aged ≥18 years with AF diagnosis who underwent CA (with first such ablation classified as ‘index ablation event’) from Jan 2017 until Oct 2023. Patients were excluded if they: 1) had less than 6 months continuous enrollment prior to the index ablation procedure; 2) underwent a left atrial appendage occlusion procedure prior to the index date. Treatment persistence for OAC in the 1-year period post-CA was assessed using descriptive statistics, including Kaplan-Meier plots and estimates. Automated machine learning was used to predict OAC use within 1-year after CA. Patients’ demographics, baseline medical conditions and clinical events prior to drug discontinuation ( e.g. , bleeding, repeated ablation, cardioversion) were included as factors of interest in the model. Area under the receiver operator curve (AUROC) was calculated, as well as importance score (w), i.e. , contribution to AUROC, for each factor. Results: 65,020 patients (mean age 69, standard deviation 10; 39% female) underwent CA in the study period (89.7% with CHA 2 DS 2 -VASc score ≥ 2 at index date). Of these patients, ~ 85% continued OACs for 3 months but only 54.9% at 1 year (Figure 1). The AUROC for the total AF population was 0.685 (95% CI: 0.671 - 0.699). Main predictors for OAC discontinuation at 1-year were CHA 2 DS 2 -VASc baseline score (w, 0.034), bleeding incidence in the follow-up period (w, 0.026), and left atrial appendage occlusion post-CA (w, 0.020). The predictors of OAC discontinuation were similar for paroxysmal (AUROC, 0.689 [95%CI 0.666-0.713]) vs persistent (AUROC, 0.668 [0.664-0.701]) AF. Conclusion: Although guidelines recommend continuing OAC after ablation if CHA 2 DS 2 -VASc score ≥ 2, discontinuation was common in US patients with AF. Machine learning developed a predictive model with reasonably good performance, identifying CHA 2 DS 2 -VASc score as the strongest predictor of guideline concordant OAC therapy in the post ablation period.