{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,3]],"date-time":"2026-03-03T00:58:50Z","timestamp":1772499530605,"version":"3.50.1"},"reference-count":85,"publisher":"MDPI AG","issue":"8","license":[{"start":{"date-parts":[[2018,8,9]],"date-time":"2018-08-09T00:00:00Z","timestamp":1533772800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100003329","name":"Ministerio de Econom\u00eda y Competitividad","doi-asserted-by":"publisher","award":["TEC2015-64678-R"],"award-info":[{"award-number":["TEC2015-64678-R"]}],"id":[{"id":"10.13039\/501100003329","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100010198","name":"Ministerio de Econom\u00eda, Industria y Competitividad, Gobierno de Espa\u00f1a","doi-asserted-by":"publisher","award":["DPI2017-83952-C3"],"award-info":[{"award-number":["DPI2017-83952-C3"]}],"id":[{"id":"10.13039\/501100010198","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100003451","name":"Euskal Herriko Unibertsitatea","doi-asserted-by":"publisher","award":["PIF15\/190"],"award-info":[{"award-number":["PIF15\/190"]}],"id":[{"id":"10.13039\/501100003451","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100003451","name":"Euskal Herriko Unibertsitatea","doi-asserted-by":"publisher","award":["GIU17\/031"],"award-info":[{"award-number":["GIU17\/031"]}],"id":[{"id":"10.13039\/501100003451","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100003086","name":"Eusko Jaurlaritza","doi-asserted-by":"publisher","award":["PRE-2016-1-0012"],"award-info":[{"award-number":["PRE-2016-1-0012"]}],"id":[{"id":"10.13039\/501100003086","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"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Entropy"],"abstract":"<jats:p>Optimal defibrillation timing guided by ventricular fibrillation (VF) waveform analysis would contribute to improved survival of out-of-hospital cardiac arrest (OHCA) patients by minimizing myocardial damage caused by futile defibrillation shocks and minimizing interruptions to cardiopulmonary resuscitation. Recently, fuzzy entropy (FuzzyEn) tailored to jointly measure VF amplitude and regularity has been shown to be an efficient defibrillation success predictor. In this study, 734 shocks from 296 OHCA patients (50 survivors) were analyzed, and the embedding dimension (m) and matching tolerance (r) for FuzzyEn and sample entropy (SampEn) were adjusted to predict defibrillation success and patient survival. Entropies were significantly larger in successful shocks and in survivors, and when compared to the available methods, FuzzyEn presented the best prediction results, marginally outperforming SampEn. The sensitivity and specificity of FuzzyEn were 83.3% and 76.7% when predicting defibrillation success, and 83.7% and 73.5% for patient survival. Sensitivities and specificities were two points above those of the best available methods, and the prediction accuracy was kept even for VF intervals as short as 2s. These results suggest that FuzzyEn and SampEn may be promising tools for optimizing the defibrillation time and predicting patient survival in OHCA patients presenting VF.<\/jats:p>","DOI":"10.3390\/e20080591","type":"journal-article","created":{"date-parts":[[2018,8,9]],"date-time":"2018-08-09T10:36:31Z","timestamp":1533810991000},"page":"591","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":18,"title":["Fuzzy and Sample Entropies as Predictors of Patient Survival Using Short Ventricular Fibrillation Recordings during out of Hospital Cardiac Arrest"],"prefix":"10.3390","volume":"20","author":[{"given":"Beatriz","family":"Chicote","sequence":"first","affiliation":[{"name":"Department of Communications Engineering, University of the Basque Country (UPV\/EHU), 48013 Bilbao, Spain"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9521-1852","authenticated-orcid":false,"given":"Unai","family":"Irusta","sequence":"additional","affiliation":[{"name":"Department of Communications Engineering, University of the Basque Country (UPV\/EHU), 48013 Bilbao, Spain"}]},{"given":"Elisabete","family":"Aramendi","sequence":"additional","affiliation":[{"name":"Department of Communications Engineering, University of the Basque Country (UPV\/EHU), 48013 Bilbao, Spain"}]},{"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 (UCLM), 16071 Cuenca, Spain"}]},{"given":"Jos\u00e9 Joaqu\u00edn","family":"Rieta","sequence":"additional","affiliation":[{"name":"BioMIT.org, Electronic Engineering Department, Universitat Polit\u00e9cnica de Valencia (UPV), 46022 Valencia, Spain"}]},{"given":"Iraia","family":"Isasi","sequence":"additional","affiliation":[{"name":"Department of Communications Engineering, University of the Basque Country (UPV\/EHU), 48013 Bilbao, Spain"}]},{"given":"Daniel","family":"Alonso","sequence":"additional","affiliation":[{"name":"Emergency Medical System (Emergentziak-Osakidetza), Basque Health Service, 20014 Donostia, Spain"}]},{"given":"Mar\u00eda del Mar","family":"Baqueriza","sequence":"additional","affiliation":[{"name":"Emergency Medical System (Emergentziak-Osakidetza), Basque Health Service, 20014 Donostia, Spain"}]},{"given":"Karlos","family":"Ibarguren","sequence":"additional","affiliation":[{"name":"Emergency Medical System (Emergentziak-Osakidetza), Basque Health Service, 20014 Donostia, Spain"}]}],"member":"1968","published-online":{"date-parts":[[2018,8,9]]},"reference":[{"key":"ref_1","first-page":"188","article-title":"EuReCa ONE-27 Nations, ONE Europe, ONE Registry: A prospective one month analysis of out-of-hospital cardiac arrest outcomes in 27 countries in Europe","volume":"105","author":"Lefering","year":"2016","journal-title":"Resuscitation"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"e67","DOI":"10.1161\/CIR.0000000000000558","article-title":"Heart Disease and Stroke Statistics-2018 Update: A Report From the American Heart Association","volume":"137","author":"Benjamin","year":"2018","journal-title":"Circulation"},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"2305","DOI":"10.1172\/JCI26381","article-title":"Mechanisms of sudden cardiac death","volume":"115","author":"Rubart","year":"2005","journal-title":"J. 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