{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,11]],"date-time":"2026-02-11T13:27:58Z","timestamp":1770816478586,"version":"3.50.1"},"reference-count":37,"publisher":"MDPI AG","issue":"6","license":[{"start":{"date-parts":[[2020,3,18]],"date-time":"2020-03-18T00:00:00Z","timestamp":1584489600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100004329","name":"Javna Agencija za Raziskovalno Dejavnost RS","doi-asserted-by":"publisher","award":["P2-0095"],"award-info":[{"award-number":["P2-0095"]}],"id":[{"id":"10.13039\/501100004329","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100003170","name":"Stiftelsen f\u00f6r Kunskaps- och Kompetensutveckling","doi-asserted-by":"publisher","award":["20180158"],"award-info":[{"award-number":["20180158"]}],"id":[{"id":"10.13039\/501100003170","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>The recent trend in electrocardiogram (ECG) device development is towards wireless body sensors applied for patient monitoring. The ultimate goal is to develop a multi-functional body sensor that will provide synchronized vital bio-signs of the monitored user. In this paper, we present an ECG sensor for long-term monitoring, which measures the surface potential difference between proximal electrodes near the heart, called differential ECG lead or differential lead, in short. The sensor has been certified as a class IIa medical device and is available on the market under the trademark Savvy ECG. An improvement from the user\u2019s perspective\u2014immediate access to the measured data\u2014is also implemented into the design. With appropriate placement of the device on the chest, a very clear distinction of all electrocardiographic waves can be achieved, allowing for ECG recording of high quality, sufficient for medical analysis. Experimental results that elucidate the measurements from a differential lead regarding sensors\u2019 position, the impact of artifacts, and potential diagnostic value, are shown. We demonstrate the sensors\u2019 potential by presenting results from its various areas of application: medicine, sports, veterinary, and some new fields of investigation, like hearth rate variability biofeedback assessment and biometric authentication.<\/jats:p>","DOI":"10.3390\/s20061695","type":"journal-article","created":{"date-parts":[[2020,3,19]],"date-time":"2020-03-19T03:54:14Z","timestamp":1584590054000},"page":"1695","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":63,"title":["Medical-Grade ECG Sensor for Long-Term Monitoring"],"prefix":"10.3390","volume":"20","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-2014-8630","authenticated-orcid":false,"given":"Aleksandra","family":"Rashkovska","sequence":"first","affiliation":[{"name":"Department of Communication Systems, Jo\u017eef Stefan Institute, Jamova cesta 39, 1000 Ljubljana, Slovenia"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0365-5294","authenticated-orcid":false,"given":"Matja\u017e","family":"Depolli","sequence":"additional","affiliation":[{"name":"Department of Communication Systems, Jo\u017eef Stefan Institute, Jamova cesta 39, 1000 Ljubljana, Slovenia"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0545-2335","authenticated-orcid":false,"given":"Ivan","family":"Toma\u0161i\u0107","sequence":"additional","affiliation":[{"name":"Division of Intelligent Future Technologies, M\u00e4lardalen University, H\u00f6gskoleplan 1, 721 23 V\u00e4ster\u00e5s, Sweden"}]},{"given":"Viktor","family":"Avbelj","sequence":"additional","affiliation":[{"name":"Department of Communication Systems, Jo\u017eef Stefan Institute, Jamova cesta 39, 1000 Ljubljana, Slovenia"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8986-489X","authenticated-orcid":false,"given":"Roman","family":"Trobec","sequence":"additional","affiliation":[{"name":"Department of Communication Systems, Jo\u017eef Stefan Institute, Jamova cesta 39, 1000 Ljubljana, Slovenia"}]}],"member":"1968","published-online":{"date-parts":[[2020,3,18]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"275","DOI":"10.1007\/BF01697566","article-title":"\u00dcber die Richtung und die manifeste Gr\u00f6sse der Potentialschwankungen im menschlichen Herzen und \u00fcber den Einfluss der Herzlage auf die Form des Elektrokardiogramms","volume":"150","author":"Einthoven","year":"1913","journal-title":"Pfl\u00fcger\u2019s Archiv f\u00fcr die gesamte Physiologie des Menschen und der Tiere"},{"key":"ref_2","unstructured":"Macfarlane, P.W., and Lawrie, T.D.V. 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