Analysis of the Time-Dependent Behaviors of Atrial Fibrillation with Electrographic Flow Mapping

Background Electrographic flow (EGF) mapping algorithms employing Horn-Schunck flow estimations can create temporospatial visualizations of atrial electrical wavefront propagations during atrial fibrillation (AF). Reproducible patterns of centrifugal EGF activation from discrete sites may represent sites of AF origin or sources. Our objectives were to assess the patterns and prevalence of AF sources using EGF mapping. Methods Unipolar electrograms were recorded for 1-minute with 64-pole basket catheters. Flow estimates were constructed by passing consecutive frames through an algorithm to learn and then compare typical wave direction patterns to describe flow-field evolution. During each 2-second segment, sites initiating centrifugal activation patterns were defined as AF sources. Maps of source location/activity duration were generated. Results The EGF method was applied to 405 prospective and retrospective patients with persistent or long-standing persistent AF. Mean age 62.5 years; mean LA size 54 mm; mean AF duration 4.6 years. EGF mapping found 6.6 ± 2.4 AF sources/patient (range 1 to 17). Distribution was 55% LA and 45% RA. Dominant sources (prevalence >20%) were demonstrated in 185 (45.7%) patients, but only 10.7% of all sources were dominant. While AF cycle length (CL) was not affected by source prevalence, CL variance significantly decreased as source prevalence increased. Conclusions Complex AF conduction patterns make ablation challenging, but EGF mapping enables detection and organization of time-dependent AF behaviors. Although many low prevalence sources are detected, they may not be clinically relevant, while higher prevalence sources seem to modulate AF. Recording durations of 1 minute facilitate source discrimination. ### Competing Interest Statement As noted in COI statement, DH has equity interest in Ablacon, Inc. and MK, PR and SC are employed by Ablacon ### Clinical Trial NCT04473963 ### Funding Statement Dr. Haines was supported in part by the Beaumont Foundation with a generous gift from Kimberly A. Whipple. The remainder of the time and effort was contributed by employees of Ablacon. ### 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: Praxisklinik Herz und Gefäße Dresden, Akademische Lehrpraxisklinik der TU Dresden Human Investigations Committee Ruhr University Bochum Research Council University Heart Center, Hamburg GmbH Institute of Experimental Cardiovascular Research Review Board Erasmus Medical Center - Medisch Ethische Toetsings Commissie (METC) 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 The raw data analyzed in this study is readily available for review.