{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,1]],"date-time":"2026-03-01T23:20:15Z","timestamp":1772407215122,"version":"3.50.1"},"reference-count":69,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2020,2,19]],"date-time":"2020-02-19T00:00:00Z","timestamp":1582070400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100014440","name":"Ministerio de Ciencia, Innovaci\u00f3n y Universidades","doi-asserted-by":"publisher","award":["DPI2017-83952-C3"],"award-info":[{"award-number":["DPI2017-83952-C3"]}],"id":[{"id":"10.13039\/100014440","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100011698","name":"Junta de Comunidades de Castilla-La Mancha","doi-asserted-by":"publisher","award":["SBPLY\/17\/180501\/000411"],"award-info":[{"award-number":["SBPLY\/17\/180501\/000411"]}],"id":[{"id":"10.13039\/501100011698","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100003359","name":"Generalitat Valenciana","doi-asserted-by":"publisher","award":["AICO\/2019\/036"],"award-info":[{"award-number":["AICO\/2019\/036"]}],"id":[{"id":"10.13039\/501100003359","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Entropy"],"abstract":"<jats:p>Atrial fibrillation (AF) is currently the most common cardiac arrhythmia, with catheter ablation (CA) of the pulmonary veins (PV) being its first line therapy. Ablation of complex fractionated atrial electrograms (CFAEs) outside the PVs has demonstrated improved long-term results, but their identification requires a reliable electrogram (EGM) fractionation estimator. This study proposes a technique aimed to assist CA procedures under real-time settings. The method has been tested on three groups of recordings: Group 1 consisted of 24 highly representative EGMs, eight of each belonging to a different AF Type. Group 2 contained the entire dataset of 119 EGMs, whereas Group 3 contained 20 pseudo-real EGMs of the special Type IV AF. Coarse-grained correlation dimension (CGCD) was computed at epochs of 1 s duration, obtaining a classification accuracy of 100% in Group 1 and 84.0\u201385.7% in Group 2, using 10-fold cross-validation. The receiver operating characteristics (ROC) analysis for highly fractionated EGMs, showed 100% specificity and sensitivity in Group 1 and 87.5% specificity and 93.6% sensitivity in Group 2. In addition, 100% of the pseudo-real EGMs were correctly identified as Type IV AF. This method can consistently express the fractionation level of AF EGMs and provides better performance than previous works. Its ability to compute fractionation in short-time can agilely detect sudden changes of AF Types and could be used for mapping the atrial substrate, thus assisting CA procedures under real-time settings for atrial substrate modification.<\/jats:p>","DOI":"10.3390\/e22020232","type":"journal-article","created":{"date-parts":[[2020,2,19]],"date-time":"2020-02-19T04:06:01Z","timestamp":1582085161000},"page":"232","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":6,"title":["Short-Time Estimation of Fractionation in Atrial Fibrillation with Coarse-Grained Correlation Dimension for Mapping the Atrial Substrate"],"prefix":"10.3390","volume":"22","author":[{"given":"Aikaterini","family":"Vraka","sequence":"first","affiliation":[{"name":"BioMIT.org, Electronic Engineering Department, Universitat Politecnica de Valencia, 46022 Valencia, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Fernando","family":"Hornero","sequence":"additional","affiliation":[{"name":"Cardiac Surgery Department, Hospital Universitari i Politecnic La Fe, 46026 Valencia, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5309-0562","authenticated-orcid":false,"given":"Vicente","family":"Bertomeu-Gonz\u00e1lez","sequence":"additional","affiliation":[{"name":"Cardiology Department, Hospital Universitario de San Juan de Alicante, 03550 Alicante, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7253-1826","authenticated-orcid":false,"given":"Joaqu\u00edn","family":"Osca","sequence":"additional","affiliation":[{"name":"Electrophysiology Section, Hospital Universitari i Politecnic La Fe, 46026 Valencia, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0942-3638","authenticated-orcid":false,"given":"Ra\u00fal","family":"Alcaraz","sequence":"additional","affiliation":[{"name":"Research Group in Electronic, Biomedical and Telecommunication Engineering, University of Castilla-La Mancha, 16071 Cuenca, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3364-6380","authenticated-orcid":false,"given":"Jos\u00e9 J.","family":"Rieta","sequence":"additional","affiliation":[{"name":"BioMIT.org, Electronic Engineering Department, Universitat Politecnica de Valencia, 46022 Valencia, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2020,2,19]]},"reference":[{"key":"ref_1","first-page":"1609","article-title":"2016 ESC Guidelines for the management of atrial fibrillation developed in collaboration with EACTS. 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