{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,11,7]],"date-time":"2025-11-07T13:36:28Z","timestamp":1762522588665,"version":"build-2065373602"},"reference-count":35,"publisher":"MDPI AG","issue":"10","license":[{"start":{"date-parts":[[2021,5,19]],"date-time":"2021-05-19T00:00:00Z","timestamp":1621382400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Ministry of Science and Higher Education of the Russian Federation within the Framework of State Support for the creation and development towards a World-Class Research Center &quot;Digital Biodesign and Personalized Healthcare.","award":["075-15-2020-926"],"award-info":[{"award-number":["075-15-2020-926"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>The availability of simple, accurate, and affordable cuffless blood pressure (BP) devices has the potential to greatly increase the compliance with measurement recommendations and the utilization of BP measurements for BP telemonitoring. The aim of this study is to evaluate the correlation between findings from routine BP measurements using a conventional sphygmomanometer with the results from a portable ECG monitor combined with photoplethysmography (PPG) for pulse wave registration in patients with arterial hypertension. Methods: The study included 500 patients aged 32\u201388 years (mean 64 \u00b1 7.9 years). Mean values from three routine BP measurements by a sphygmomanometer with cuff were selected for comparison; within one minute after the last measurement, an electrocardiogram (ECG) was recorded for 3 min in the standard lead I using a smartphone-case based single-channel ECG monitor (CardioQVARK\u00ae-limited responsibility company \u201cL-CARD\u201d, Moscow, Russia) simultaneously with a PPG pulse wave recording. Using a combination of the heart signal with the PPG, levels of systolic and diastolic BP were determined based on machine learning using a previously developed and validated algorithm and were compared with sphygmomanometer results. Results: According to the Bland\u2013Altman analysis, SD for systolic BP was 3.63, and bias was 0.32 for systolic BP. SD was 2.95 and bias was 0.61 for diastolic BP. The correlation between the results from the sphygmomanometer and the cuffless method was 0.89 (p = 0.001) for systolic and 0.87 (p = 0.002) for diastolic BP. Conclusion: Blood pressure measurements on a smartphone-case without a cuff are encouraging. However, further research is needed to improve the accuracy and reliability of clinical use in the majority of patients.<\/jats:p>","DOI":"10.3390\/s21103525","type":"journal-article","created":{"date-parts":[[2021,5,19]],"date-time":"2021-05-19T21:49:21Z","timestamp":1621460961000},"page":"3525","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":39,"title":["Cuffless Blood Pressure Measurement Using a Smartphone-Case Based ECG Monitor with Photoplethysmography in Hypertensive Patients"],"prefix":"10.3390","volume":"21","author":[{"given":"Zhanna","family":"Sagirova","sequence":"first","affiliation":[{"name":"Department of Cardiology, Functional and Ultrasound Diagnostics of N.V. Sklifosovsky, Institute for Clinical Medicine, I.M. Sechenov First Moscow State Medical University, 119435 Moscow, Russia"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4717-1272","authenticated-orcid":false,"given":"Natalia","family":"Kuznetsova","sequence":"additional","affiliation":[{"name":"Research Center \u201cDigital Biodesign and Personalized Healthcare\u201d, I.M. Sechenov First Moscow State Medical University, 119991 Moscow, Russia"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0243-6724","authenticated-orcid":false,"given":"Nana","family":"Gogiberidze","sequence":"additional","affiliation":[{"name":"Department of Cardiology, Functional and Ultrasound Diagnostics of N.V. Sklifosovsky, Institute for Clinical Medicine, I.M. Sechenov First Moscow State Medical University, 119435 Moscow, Russia"}]},{"given":"Daria","family":"Gognieva","sequence":"additional","affiliation":[{"name":"Research Center \u201cDigital Biodesign and Personalized Healthcare\u201d, I.M. Sechenov First Moscow State Medical University, 119991 Moscow, Russia"}]},{"given":"Aleksandr","family":"Suvorov","sequence":"additional","affiliation":[{"name":"Centre for Analysis of Complex Systems, I.M. Sechenov First Moscow State Medical University, 119991 Moscow, Russia"}]},{"given":"Petr","family":"Chomakhidze","sequence":"additional","affiliation":[{"name":"Research Center \u201cDigital Biodesign and Personalized Healthcare\u201d, I.M. Sechenov First Moscow State Medical University, 119991 Moscow, Russia"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7124-2096","authenticated-orcid":false,"given":"Stefano","family":"Omboni","sequence":"additional","affiliation":[{"name":"Department of Cardiology, Functional and Ultrasound Diagnostics of N.V. Sklifosovsky, Institute for Clinical Medicine, I.M. Sechenov First Moscow State Medical University, 119435 Moscow, Russia"},{"name":"Italian Institute of Telemedicine, 21048 Solbiate Arno, Italy"}]},{"given":"Hugo","family":"Saner","sequence":"additional","affiliation":[{"name":"Department of Cardiology, Functional and Ultrasound Diagnostics of N.V. Sklifosovsky, Institute for Clinical Medicine, I.M. Sechenov First Moscow State Medical University, 119435 Moscow, Russia"},{"name":"ARTORG Center for Biomedical Engineering Research, University of Bern, 3008 Bern, Switzerland"},{"name":"Institute for Social and Preventive Medicine, University of Bern, 3012 Bern, Switzerland"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5124-6383","authenticated-orcid":false,"given":"Philippe","family":"Kopylov","sequence":"additional","affiliation":[{"name":"Research Center \u201cDigital Biodesign and Personalized Healthcare\u201d, I.M. Sechenov First Moscow State Medical University, 119991 Moscow, Russia"}]}],"member":"1968","published-online":{"date-parts":[[2021,5,19]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"2073","DOI":"10.1001\/jama.2017.18209","article-title":"The 2017 Clinical Practice Guideline for High Blood Pressure","volume":"318","author":"Whelton","year":"2017","journal-title":"JAMA"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"959","DOI":"10.1001\/jama.2013.184182","article-title":"Prevalence, Awareness, Treatment, and Control of Hypertension in Rural and Urban Communities in High-, Middle-, and Low-Income Countries","volume":"310","author":"Chow","year":"2013","journal-title":"JAMA"},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"1719","DOI":"10.1093\/eurheartj\/eht565","article-title":"Central blood pressure: Current evidence and clinical importance","volume":"35","author":"McEniery","year":"2014","journal-title":"Eur. 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