Ablation STrategies for Repeat PrOcedures in Atrial Fibrillation Recurrences despite Durable Pulmonary Vein Isolation ASTRO - AF Trial

Background Ablation strategies for patients with symptomatic atrial fibrillation (AF) and isolated pulmonary veins (PV) vary and their impact on arrhythmia recurrence remains unclear. This prospective randomized German multi—center trial sought to compare two ablation strategies in this patient cohort. Methods Patients with AF despite durable PV isolation were randomly assigned at seven centers to undergo low-voltage area (LVA) ablation using 3D mapping and irrigated radiofrequency current ablation (group A) or empirical left atrial appendage isolation (LAAI) utilizing the cryoballoon (CB) followed by staged interventional LAA closure (group B). The primary endpoint was freedom from atrial tachyarrhythmias between 91 and 365 days after index ablation. The study was powered for superiority of LAAI compared to LVA. Results Patients (40% female, mean age 68.8±8 years) with paroxysmal (32%) or persistent AF (68%) were randomized to undergo LVA ablation (n=79) or CB guided LAAI (n=82). After a planned interim analysis enrollment was halted on January 10th 2023. In the LAAI group 77/82 LAAs were successfully isolated with subsequent LAAC in 57 patients. Procedure related complications occurred in 4 (5%) and 11 (13.5%) patients in group A and B, respectively (P=0.10). The median follow-up was 367 (IQR 359-378) days. The Kaplan Meier point estimate for the freedom from a primary endpoint event was 51.7% (CI 40.9-65.4%) for group A and 55.5% (CI 44.4-69.2%; p=0.8069). Conclusions The present study did not detect superiority of CB guided LAAI over LVA ablation in patients with AF despite durable PVI. It was registered at What is new? What are the clinical implications? ### Competing Interest Statement The authors have declared no competing interest. ### Clinical Trial https://clinicaltrials.gov/study/[NCT04056390][1] ### Funding Statement The trial was supported by an unrestricted educational research grant of Medtronic. ### Author Declarations I confirm all relevant ethical guidelines have been followed, and any necessary IRB and/or ethics committee approvals have been obtained. Yes The details of the IRB/oversight body that provided approval or exemption for the research described are given below: The trial was approved by the ethics committee of the Landesaerztekammer Hessen (2023-3251-evBO) and complies with the declaration of Helsinki. I confirm that all necessary patient/participant consent has been obtained and the appropriate institutional forms have been archived, and that any patient/participant/sample identifiers included were not known to anyone (e.g., hospital staff, patients or participants themselves) outside the research group so cannot be used to identify individuals. Yes I understand that all clinical trials and any other prospective interventional studies must be registered with an ICMJE-approved registry, such as ClinicalTrials.gov. I confirm that any such study reported in the manuscript has been registered and the trial registration ID is provided (note: if posting a prospective study registered retrospectively, please provide a statement in the trial ID field explaining why the study was not registered in advance). Yes I have followed all appropriate research reporting guidelines, such as any relevant EQUATOR Network research reporting checklist(s) and other pertinent material, if applicable. Yes Data can be accessed with permission of the author [1]: /lookup/external-ref?link_type=CLINTRIALGOV&access_num=NCT04056390&atom=%2Fmedrxiv%2Fearly%2F2024%2F04%2F12%2F2024.04.09.24305585.atom