{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,22]],"date-time":"2026-04-22T23:55:22Z","timestamp":1776902122245,"version":"3.51.2"},"reference-count":38,"publisher":"MDPI AG","issue":"7","license":[{"start":{"date-parts":[[2021,7,19]],"date-time":"2021-07-19T00:00:00Z","timestamp":1626652800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001691","name":"Japan Society for the Promotion of Science","doi-asserted-by":"publisher","award":["JP21K08140"],"award-info":[{"award-number":["JP21K08140"]}],"id":[{"id":"10.13039\/501100001691","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Entropy"],"abstract":"<jats:p>It has been recognized that heart rate variability (HRV), defined as the fluctuation of ventricular response intervals in atrial fibrillation (AFib) patients, is not completely random, and its nonlinear characteristics, such as multiscale entropy (MSE), contain clinically significant information. We investigated the relationship between ischemic stroke risk and HRV with a large number of stroke-na\u00efve AFib patients (628 patients), focusing on those who had never developed an ischemic\/hemorrhagic stroke before the heart rate measurement. The CHA2DS2\u2212VASc score was calculated from the baseline clinical characteristics, while the HRV analysis was made from the recording of morning, afternoon, and evening. Subsequently, we performed Kaplan\u2013Meier method and cumulative incidence function with mortality as a competing risk to estimate the survival time function. We found that patients with sample entropy (SE(s)) \u2265 0.68 at 210 s had a significantly higher risk of an ischemic stroke occurrence in the morning recording. Meanwhile, the afternoon recording showed that those with SE(s)\u00a0\u2265 0.76 at 240 s and SE(s)\u00a0\u2265 0.78 at 270 s had a significantly lower risk of ischemic stroke occurrence. Therefore, SE(s) at 210 s (morning) and 240 s \u2264 s \u2264 270 s (afternoon) demonstrated a statistically significant predictive value for ischemic stroke in stroke-na\u00efve AFib patients.<\/jats:p>","DOI":"10.3390\/e23070918","type":"journal-article","created":{"date-parts":[[2021,7,19]],"date-time":"2021-07-19T21:39:15Z","timestamp":1626730755000},"page":"918","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":5,"title":["Ischemic Stroke Risk Assessment by Multiscale Entropy Analysis of Heart Rate Variability in Patients with Persistent Atrial Fibrillation"],"prefix":"10.3390","volume":"23","author":[{"given":"Ghina","family":"Chairina","sequence":"first","affiliation":[{"name":"Graduate School of Science and Technology, Kwansei Gakuin University, Sanda 669-1337, Japan"},{"name":"Faculty of Mathematics and Natural Sciences, Universitas Padjadjaran, Sumedang 45363, Indonesia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Kohzoh","family":"Yoshino","sequence":"additional","affiliation":[{"name":"Graduate School of Science and Technology, Kwansei Gakuin University, Sanda 669-1337, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5433-7002","authenticated-orcid":false,"given":"Ken","family":"Kiyono","sequence":"additional","affiliation":[{"name":"Graduate School of Engineering Science, Osaka University, Toyonaka 560-8531, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Eiichi","family":"Watanabe","sequence":"additional","affiliation":[{"name":"Department of Cardiology, Fujita Health University Bantane Hospital, Nagoya 454-8509, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2021,7,19]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"2370","DOI":"10.1001\/jama.285.18.2370","article-title":"Prevalence of Diagnosed Atrial Fibrillation in Adults","volume":"285","author":"Go","year":"2001","journal-title":"JAMA"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"983","DOI":"10.1161\/01.STR.22.8.983","article-title":"Atrial fibrillation as an independent risk factor for stroke: The Framingham Study","volume":"22","author":"Wolf","year":"1991","journal-title":"Stroke"},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"43","DOI":"10.1159\/000255973","article-title":"Stroke Associated with Atrial Fibrillation\u2014Incidence and Early Outcomes in the North Dublin Population Stroke Study","volume":"29","author":"Hannon","year":"2010","journal-title":"Cerebrovasc. 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