Modelling Coagulation, Heat Transfer and Blood Flow in the Left Atrium during Catheter Ablation for Atrial Fibrillation Patients

Modelling Coagulation, Heat Transfer and Blood Flow in the Left Atrium during Catheter Ablation for Atrial Fibrillation Patients | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article Modelling Coagulation, Heat Transfer and Blood Flow in the Left Atrium during Catheter Ablation for Atrial Fibrillation Patients Paolo Melidoro, Steven E. Williams, Gregory Y.H Lip, Magdalena Klis, and 2 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-8745185/v1 This work is licensed under a CC BY 4.0 License Status: Under Review Version 1 posted 4 You are reading this latest preprint version Abstract Atrial fibrillation (AF) is the most common cardiac arrhythmia and increases stroke risk and reduces quality of life. Left atrial catheter ablation (LACA) restores sinus rhythm by targeting abnormal electrical sources. Pulmonary vein isolation (PVI) is the most common approach, while left atrial appendage electrical isolation (LAAEI) is used selectively but may raise thrombus risk. Computational fluid dynamics (CFD) has been used to model thrombogenesis during LACA, but the relationship between blood temperature and coagulation is yet to be modelled. We performed twenty-nine simulations coupling CFD with heat transfer during PVI and related thrombogenesis in the left atrium. These included PVI at 80 °C and 60 °C, LAAEI at 80 °C, and ablation sites at increasing distances from the LAA. Experimental data linking temperature and coagulation were used to calibrate a thermal exposure model, alongside transport and reaction equations for coagulation proteins, including fibrin. At 80 °C, PVI produced variable fibrin formation across the PVs, with no significant differences between PVs or correlation with PV velocity. At 60 °C, fibrin remained below the thrombus threshold, and fibrin at 80 °C was significantly greater (p = 1.91×10⁻⁶). Including LAAEI produced a significant overall difference in fibrin among sites, but no pairwise differences remained after correction. Fibrin decreased with increasing distance from the LAA orifice, showing a significant negative correlation after three and twelve cycles. These results highlight risks of temperature-dependent thrombogenesis and suggest reduced thrombus risk with more distant ablation from the LAA. Full Text Additional Declarations No competing interests reported. Cite Share Download PDF Status: Under Review Version 1 posted Editorial decision: Revision requested 22 Feb, 2026 Editor assigned by journal 04 Feb, 2026 Submission checks completed at journal 03 Feb, 2026 First submitted to journal 30 Jan, 2026 You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-8745185","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":595045588,"identity":"3d8342cf-5a8f-4238-bc57-df4266586674","order_by":0,"name":"Paolo Melidoro","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAA+klEQVRIiWNgGAWjYHACxgMgko+ZwQBI2RgwsEOEDfDpAWthg2hJM2BgJloLRNFhwlrM2Q8fOPCBYZscGzvzxscVFeeN+ZsZGD/8YDhsjEuLZU9awsEZDLeN2ZjZig3PnLltJnGYgVmyh+GwGS4tBgdyDA7zMNxObGPmMZNsbLttYwB0mDTQhTY4tZx/A9ZSD9VyDqSF+TdeLTcgtiSwQbQcMANqYQPZgtNhljOeAf1icNuwDeSXhjPJxhKHGdssewzScXrfnD/54IMPFbfl+fkPb3zYUGFn2N/efPjGjwprwwZcDkMiYYCxAW9E4o3jUTAKRsEoGAVgAACzuU1OuwRfDQAAAABJRU5ErkJggg==","orcid":"","institution":"King's College London","correspondingAuthor":true,"prefix":"","firstName":"Paolo","middleName":"","lastName":"Melidoro","suffix":""},{"id":595045589,"identity":"117bc424-ea94-41cc-891f-285cc02424fc","order_by":1,"name":"Steven E. 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