{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,12]],"date-time":"2025-10-12T03:05:43Z","timestamp":1760238343389,"version":"build-2065373602"},"reference-count":69,"publisher":"MDPI AG","issue":"15","license":[{"start":{"date-parts":[[2020,7,27]],"date-time":"2020-07-27T00:00:00Z","timestamp":1595808000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Ventricular fibrillation (VF) signals are characterized by highly volatile and erratic electrical impulses, the analysis of which is difficult given the complex behavior of the heart rhythms in the left (LV) and right ventricles (RV), as sometimes shown in intracardiac recorded Electrograms (EGM). However, there are few studies that analyze VF in humans according to the simultaneous behavior of heart signals in the two ventricles. The objective of this work was to perform a spectral and a non-linear analysis of the recordings of 22 patients with Congestive Heart Failure (CHF) and clinical indication for a cardiac resynchronization device, simultaneously obtained in LV and RV during induced VF in patients with a Biventricular Implantable Cardioverter Defibrillator (BICD) Contak Renewal IVTM (Boston Sci.). The Fourier Transform was used to identify the spectral content of the first six seconds of signals recorded in the RV and LV simultaneously. In addition, measurements that were based on Information Theory were scrutinized, including Entropy and Mutual Information. The results showed that in most patients the spectral envelopes of the EGM sources of RV and LV were complex, different, and with several frequency peaks. In addition, the Dominant Frequency (DF) in the LV was higher than in the RV, while the Organization Index (OI) had the opposite trend. The entropy measurements were more regular in the RV than in the LV, thus supporting the spectral findings. We can conclude that basic stochastic processing techniques should be scrutinized with caution and from basic to elaborated techniques, but they can provide us with useful information on the biosignals from both ventricles during VF.<\/jats:p>","DOI":"10.3390\/s20154162","type":"journal-article","created":{"date-parts":[[2020,7,27]],"date-time":"2020-07-27T04:39:50Z","timestamp":1595824790000},"page":"4162","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Spectral Analysis and Mutual Information Estimation of Left and Right Intracardiac Electrograms during Ventricular Fibrillation"],"prefix":"10.3390","volume":"20","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-8639-0980","authenticated-orcid":false,"given":"Milton Fabricio","family":"P\u00e9rez-Guti\u00e9rrez","sequence":"first","affiliation":[{"name":"Departamento de El\u00e9ctrica y Electr\u00f3nica, Universidad de las Fuerzas Armadas ESPE, Av. General Rumi\u00f1ahui s\/n, Sangolqu\u00ed 171-5-231B, Ecuador"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6560-9429","authenticated-orcid":false,"given":"Juan Jos\u00e9","family":"S\u00e1nchez-Mu\u00f1oz","sequence":"additional","affiliation":[{"name":"Arrhythmia Unit and Electrophysiology, Department of Cardiology, Virgen de la Arrixaca University Hospital, Instituto Murciano de Investigaci\u00f3n Biosanitaria, 30120 Murcia, Spain"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2196-3514","authenticated-orcid":false,"given":"Mayra","family":"Erazo-Rodas","sequence":"additional","affiliation":[{"name":"Departamento de El\u00e9ctrica y Electr\u00f3nica, Universidad de las Fuerzas Armadas ESPE, Av. General Rumi\u00f1ahui s\/n, Sangolqu\u00ed 171-5-231B, Ecuador"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7403-165X","authenticated-orcid":false,"given":"Alicia","family":"Guerrero-Curieses","sequence":"additional","affiliation":[{"name":"Departamento de Teor\u00eda de la Se\u00f1al y Comunicaciones, Sistemas Telem\u00e1ticos y Computaci\u00f3n, Universidad Rey Juan Carlos, 28943 Fuenlabrada, Spain"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7827-3197","authenticated-orcid":false,"given":"Estrella","family":"Everss","sequence":"additional","affiliation":[{"name":"Departamento de Teor\u00eda de la Se\u00f1al y Comunicaciones, Sistemas Telem\u00e1ticos y Computaci\u00f3n, Universidad Rey Juan Carlos, 28943 Fuenlabrada, Spain"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4709-1993","authenticated-orcid":false,"given":"Aurelio","family":"Quesada-Dorador","sequence":"additional","affiliation":[{"name":"Arrhythmia Unit, Department of Cardiology, Hospital General de Valencia, 46014 Valencia, Spain"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1495-8389","authenticated-orcid":false,"given":"Ricardo","family":"Ruiz-Granell","sequence":"additional","affiliation":[{"name":"Arrhythmia Unit, Department of Cardiology, Hospital Cl\u00ednico Universitario, Av. Blasco Iba\u00f1ez, 17, 46010 Valencia, Spain"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7352-6597","authenticated-orcid":false,"given":"Alicia","family":"Ib\u00e1\u00f1ez-Criado","sequence":"additional","affiliation":[{"name":"Arrhythmia Unit, Department of Cardiology, Hospital Cl\u00ednico de Alicante, 03010 Alicante, Spain"}]},{"given":"Alex","family":"Bellver-Navarro","sequence":"additional","affiliation":[{"name":"Arrhythmia Unit, Hospital General de Castell\u00f3n, 12004 Castell\u00f3n, Spain"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0426-8912","authenticated-orcid":false,"given":"Jos\u00e9 Luis","family":"Rojo-\u00c1lvarez","sequence":"additional","affiliation":[{"name":"Departamento de Teor\u00eda de la Se\u00f1al y Comunicaciones, Sistemas Telem\u00e1ticos y Computaci\u00f3n, Universidad Rey Juan Carlos, 28943 Fuenlabrada, Spain"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1928-865X","authenticated-orcid":false,"given":"Arcadi","family":"Garc\u00eda-Alberola","sequence":"additional","affiliation":[{"name":"Arrhythmia Unit and Electrophysiology, Department of Cardiology, Virgen de la Arrixaca University Hospital, Instituto Murciano de Investigaci\u00f3n Biosanitaria, 30120 Murcia, Spain"}]}],"member":"1968","published-online":{"date-parts":[[2020,7,27]]},"reference":[{"key":"ref_1","unstructured":"(2017). 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