{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,26]],"date-time":"2026-01-26T21:45:23Z","timestamp":1769463923513,"version":"3.49.0"},"reference-count":32,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2026,1,23]],"date-time":"2026-01-23T00:00:00Z","timestamp":1769126400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001871","name":"Foundation for Science and Technology","doi-asserted-by":"publisher","award":["PTDC\/EMD-EMD\/0980\/2020"],"award-info":[{"award-number":["PTDC\/EMD-EMD\/0980\/2020"]}],"id":[{"id":"10.13039\/501100001871","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Mathematics"],"abstract":"<jats:p>Coronary artery disease (CAD) remains the leading cause of cardiovascular mortality worldwide. Accurate and non-invasive quantification of coronary hemodynamics, namely in the right coronary artery (RCA), is essential for clinical decision-making but remains challenging due to the complex interaction among vessel geometry, pulsatile flow, and blood rheology. This study presents and validates a transparent computational framework for non-invasive fractional flow reserve (FFR) estimation using patient-specific RCA geometries reconstructed from coronary computed tomography angiography (CCTA) using SimVascular 27-03-2023. The proposed workflow integrates realistic boundary conditions through a Womersley velocity profile and a three-element Windkessel outlet model, coupled with a viscoelastic blood rheology formulation (sPTT) implemented via user-defined functions (UDFs). This work integrates all clinically relevant conditions of invasive FFR assessment into a single patient-specific computational framework, while delivering results within a time frame compatible with clinical practice, representing a meaningful methodological advance. The methodology was applied to seven patient-specific cases, and the resulting non-invasive FFR values were compared with both invasive wire-based measurements and commercial HeartFlow\u00ae outputs (Mountain View, CA, USA). Under hyperemic conditions, the computed FFR values showed strong agreement with invasive references, with a mean relative error of 8.4% \u00b1 6.3%, showing diagnostic consistency similar to that of HeartFlow\u00ae (8.3% \u00b1 8.1%) for the selected dataset. These findings demonstrate the ability of the proposed CFD-based pipeline to accurately replicate physiological coronary behavior under hyperemia. This novel workflow provides a fully on-site, open-source, reproducible, and cost-effective framework. Ultimately, this study advances the clinical applicability of non-invasive CFD tools for the functional assessment of CAD, particularly in the RCA.<\/jats:p>","DOI":"10.3390\/math14030395","type":"journal-article","created":{"date-parts":[[2026,1,23]],"date-time":"2026-01-23T17:52:38Z","timestamp":1769190758000},"page":"395","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["A Computational Framework for FFR Estimation in Right Coronary Arteries: From CFD Simulation to Clinical Validation"],"prefix":"10.3390","volume":"14","author":[{"ORCID":"https:\/\/orcid.org\/0009-0009-3974-5302","authenticated-orcid":false,"given":"Francisco P.","family":"Oliveira","sequence":"first","affiliation":[{"name":"Engineering Faculty, University of Porto, Rua Dr. Roberto Frias, s\/n, 4200-465 Porto, Portugal"},{"name":"Institute of Science and Innovation in Mechanical and Industrial Engineering (LAETA-INEGI), Campus of FEUP, Rua Dr. Roberto Frias, 400, 4200-465 Porto, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6962-9937","authenticated-orcid":false,"given":"Maria","family":"Fernandes","sequence":"additional","affiliation":[{"name":"Engineering Faculty, University of Porto, Rua Dr. Roberto Frias, s\/n, 4200-465 Porto, Portugal"},{"name":"Institute of Science and Innovation in Mechanical and Industrial Engineering (LAETA-INEGI), Campus of FEUP, Rua Dr. Roberto Frias, 400, 4200-465 Porto, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7362-3597","authenticated-orcid":false,"given":"Nuno","family":"Dias Ferreira","sequence":"additional","affiliation":[{"name":"Cardiology Department, Unidade Local de Sa\u00fade de Gaia e Espinho, R. Concei\u00e7\u00e3o Fernandes, s\/n, 4434-502 Vila Nova de Gaia, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1428-1651","authenticated-orcid":false,"given":"Diogo","family":"Santos-Ferreira","sequence":"additional","affiliation":[{"name":"Cardiology Department, Unidade Local de Sa\u00fade de Gaia e Espinho, R. Concei\u00e7\u00e3o Fernandes, s\/n, 4434-502 Vila Nova de Gaia, Portugal"},{"name":"UnIC@RISE, Department of Surgery and Physiology, Faculty of Medicine, University of Porto, Alameda Prof. Hern\u00e2ni Monteiro, 4200-319 Porto, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4168-2207","authenticated-orcid":false,"given":"Saima","family":"Mushtaq","sequence":"additional","affiliation":[{"name":"Department of Perioperative Cardiology and Cardiovascular Imaging, Centro Cardiologico Monzino IRCCS, 20138 Milan, Italy"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1339-6679","authenticated-orcid":false,"given":"Gianluca","family":"Pontone","sequence":"additional","affiliation":[{"name":"Department of Perioperative Cardiology and Cardiovascular Imaging, Centro Cardiologico Monzino IRCCS, 20138 Milan, Italy"},{"name":"Department of Biomedical, Surgical and Dental Sciences, University of Milan, 20122 Milan, Italy"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5260-5613","authenticated-orcid":false,"given":"Ricardo","family":"Ladeiras-Lopes","sequence":"additional","affiliation":[{"name":"UnIC@RISE, Department of Surgery and Physiology, Faculty of Medicine, University of Porto, Alameda Prof. Hern\u00e2ni Monteiro, 4200-319 Porto, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9582-7881","authenticated-orcid":false,"given":"Nuno","family":"Bettencourt","sequence":"additional","affiliation":[{"name":"UnIC@RISE, Department of Surgery and Physiology, Faculty of Medicine, University of Porto, Alameda Prof. Hern\u00e2ni Monteiro, 4200-319 Porto, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8726-0942","authenticated-orcid":false,"given":"Lu\u00edsa C.","family":"Sousa","sequence":"additional","affiliation":[{"name":"Engineering Faculty, University of Porto, Rua Dr. Roberto Frias, s\/n, 4200-465 Porto, Portugal"},{"name":"Institute of Science and Innovation in Mechanical and Industrial Engineering (LAETA-INEGI), Campus of FEUP, Rua Dr. Roberto Frias, 400, 4200-465 Porto, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2362-6538","authenticated-orcid":false,"given":"S\u00f3nia I. S.","family":"Pinto","sequence":"additional","affiliation":[{"name":"Engineering Faculty, University of Porto, Rua Dr. Roberto Frias, s\/n, 4200-465 Porto, Portugal"},{"name":"Institute of Science and Innovation in Mechanical and Industrial Engineering (LAETA-INEGI), Campus of FEUP, Rua Dr. Roberto Frias, 400, 4200-465 Porto, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2026,1,23]]},"reference":[{"key":"ref_1","unstructured":"World Health Organization (2025, May 10). Cardiovascular Diseases (CVDs) Fact Sheet. Available online: https:\/\/www.who.int\/news-room\/fact-sheets\/detail\/cardiovascular-diseases-(cvds)."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"2233","DOI":"10.1016\/j.jacc.2012.11.083","article-title":"Computational Fluid Dynamics Applied to Cardiac Computed Tomography for Noninvasive Quantification of Fractional Flow Reserve: Scientific Basis","volume":"61","author":"Taylor","year":"2013","journal-title":"J. Am. Coll. 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