{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,19]],"date-time":"2026-02-19T15:47:46Z","timestamp":1771516066563,"version":"3.50.1"},"reference-count":32,"publisher":"MDPI AG","issue":"22","license":[{"start":{"date-parts":[[2021,11,18]],"date-time":"2021-11-18T00:00:00Z","timestamp":1637193600000},"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>Sudden Cardiac Death (SCD) is an unexpected sudden death due to a loss of heart function and represents more than 50% of the deaths from cardiovascular diseases. Since cardiovascular problems change the features in the electrical signal of the heart, if significant changes are found with respect to a reference signal (healthy), then it is possible to indicate in advance a possible SCD occurrence. This work proposes SCD identification using Electrocardiogram (ECG) signals and a sparse representation technique. Moreover, the use of fixed feature ranking is avoided by considering a dictionary as a flexible set of features where each sparse representation could be seen as a dynamic feature extraction process. In this way, the involved features may differ within the dictionary\u2019s margin of similarity, which is better-suited to the large number of variations that an ECG signal contains. The experiments were carried out using the ECG signals from the MIT\/BIH-SCDH and the MIT\/BIH-NSR databases. The results show that it is possible to achieve a detection 30 min before the SCD event occurs, reaching an an accuracy of 95.3% under the common scheme, and 80.5% under the proposed multi-class scheme, thus being suitable for detecting a SCD episode in advance.<\/jats:p>","DOI":"10.3390\/s21227666","type":"journal-article","created":{"date-parts":[[2021,11,19]],"date-time":"2021-11-19T02:43:09Z","timestamp":1637289789000},"page":"7666","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":15,"title":["ECG-Based Identification of Sudden Cardiac Death through Sparse Representations"],"prefix":"10.3390","volume":"21","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-4820-3363","authenticated-orcid":false,"given":"Josue R.","family":"Vel\u00e1zquez-Gonz\u00e1lez","sequence":"first","affiliation":[{"name":"Department of Computational Science, National Institute of Astrophysics, Optics, and Electronics, Santa Maria Tonantzintla, Puebla 72840, Mexico"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8623-091X","authenticated-orcid":false,"given":"Hayde","family":"Peregrina-Barreto","sequence":"additional","affiliation":[{"name":"Department of Computational Science, National Institute of Astrophysics, Optics, and Electronics, Santa Maria Tonantzintla, Puebla 72840, Mexico"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2785-5060","authenticated-orcid":false,"given":"Jose J.","family":"Rangel-Magdaleno","sequence":"additional","affiliation":[{"name":"Department of Electronics, National Institute of Astrophysics, Optics, and Electronics, Santa Maria Tonantzintla, Puebla 72840, Mexico"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8515-2489","authenticated-orcid":false,"given":"Juan M.","family":"Ramirez-Cortes","sequence":"additional","affiliation":[{"name":"Department of Electronics, National Institute of Astrophysics, Optics, and Electronics, Santa Maria Tonantzintla, Puebla 72840, Mexico"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9559-0220","authenticated-orcid":false,"given":"Juan P.","family":"Amezquita-Sanchez","sequence":"additional","affiliation":[{"name":"Facultad de Ingenier\u00eda, Universidad Aut\u00f3noma de Quer\u00e9taro, Av R\u00edo Moctezuma 249, San Juan del Rio 76807, Mexico"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2021,11,18]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1134","DOI":"10.1161\/CIRCULATIONAHA.109.899799","article-title":"Community approaches to improve resuscitation after out-of-hospital sudden cardiac arrest","volume":"121","author":"Rea","year":"2010","journal-title":"Circulation"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"620","DOI":"10.1161\/CIRCULATIONAHA.111.023838","article-title":"Epidemiology and genetics of sudden cardiac death","volume":"125","author":"Deo","year":"2012","journal-title":"Circulation"},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"2335","DOI":"10.1161\/CIRCULATIONAHA.110.976092","article-title":"Sudden cardiac death prediction and prevention: Report from a National Heart, Lung, and Blood Institute and Heart Rhythm Society Workshop","volume":"122","author":"Fishman","year":"2010","journal-title":"Circulation"},{"key":"ref_4","unstructured":"Myerburg, R.J. 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