{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,9]],"date-time":"2026-07-09T15:53:05Z","timestamp":1783612385985,"version":"3.55.0"},"reference-count":30,"publisher":"MDPI AG","issue":"9","license":[{"start":{"date-parts":[[2015,9,17]],"date-time":"2015-09-17T00:00:00Z","timestamp":1442448000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Guangdong Innovation Research Team Fund for Low-cost Healthcare Technologies in China","award":["GIRTF-LCHT"],"award-info":[{"award-number":["GIRTF-LCHT"]}]},{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["61401453"],"award-info":[{"award-number":["61401453"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"name":"STS Key Health Program of Chinese Academy of Sciences","award":["KFJEW-STS-097"],"award-info":[{"award-number":["KFJEW-STS-097"]}]},{"name":"STS Key Health Program of Chinese Academy of Sciences","award":["KFJ-EW-STS-095"],"award-info":[{"award-number":["KFJ-EW-STS-095"]}]},{"name":"External Cooperation Program of Chinese Academy of Sciences","award":["GJHZ1212"],"award-info":[{"award-number":["GJHZ1212"]}]},{"name":"Key Lab for Health Informatics of Chinese Academy of Sciences,"},{"name":"Peacock Program to Attract Overseas High-Caliber Talents to Shenzhen"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Cardiovascular disease, like hypertension, is one of the top killers of human life and early detection of cardiovascular disease is of great importance. However, traditional medical devices are often bulky and expensive, and unsuitable for home healthcare. In this paper, we proposed an easy and inexpensive technique to estimate continuous blood pressure from the heart sound signals acquired by the microphone of a smartphone.  A cold-pressor experiment was performed in 32 healthy subjects, with a smartphone to acquire heart sound signals and with a commercial device to measure continuous blood pressure. The Fourier spectrum of the second heart sound and the blood pressure were regressed using a support vector machine, and the accuracy of the regression was evaluated using 10-fold cross-validation. Statistical analysis showed that the mean correlation coefficients between the predicted values from the regression model and the measured values from the commercial device were 0.707, 0.712, and 0.748 for systolic, diastolic, and mean blood pressure, respectively, and that the mean errors were less than 5 mmHg, with standard deviations less than 8 mmHg. These results suggest that this technique is of potential use for cuffless and continuous blood pressure monitoring and it has promising application in home healthcare services.<\/jats:p>","DOI":"10.3390\/s150923653","type":"journal-article","created":{"date-parts":[[2015,9,17]],"date-time":"2015-09-17T16:40:26Z","timestamp":1442508026000},"page":"23653-23666","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":47,"title":["Cuffless and Continuous Blood Pressure Estimation from the Heart Sound Signals"],"prefix":"10.3390","volume":"15","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-9812-5690","authenticated-orcid":false,"given":"Rong-Chao","family":"Peng","sequence":"first","affiliation":[{"name":"Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen 518055, China"},{"name":"Shenzhen College of Advanced Technology, University of Chinese Academy of Sciences,  Shenzhen 518055, China"},{"name":"Key Lab for Health Informatics of Chinese Academy of Sciences (HICAS),  Shenzhen 518055, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Wen-Rong","family":"Yan","sequence":"additional","affiliation":[{"name":"Department of Physics and Materials Science, City University of Hong Kong, Hong Kong 999077, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ning-Ling","family":"Zhang","sequence":"additional","affiliation":[{"name":"Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen 518055, China"},{"name":"Shenzhen College of Advanced Technology, University of Chinese Academy of Sciences,  Shenzhen 518055, China"},{"name":"Key Lab for Health Informatics of Chinese Academy of Sciences (HICAS),  Shenzhen 518055, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Wan-Hua","family":"Lin","sequence":"additional","affiliation":[{"name":"Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen 518055, China"},{"name":"Key Lab for Health Informatics of Chinese Academy of Sciences (HICAS),  Shenzhen 518055, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Xiao-Lin","family":"Zhou","sequence":"additional","affiliation":[{"name":"Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen 518055, China"},{"name":"Key Lab for Health Informatics of Chinese Academy of Sciences (HICAS),  Shenzhen 518055, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yuan-Ting","family":"Zhang","sequence":"additional","affiliation":[{"name":"Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen 518055, China"},{"name":"Key Lab for Health Informatics of Chinese Academy of Sciences (HICAS),  Shenzhen 518055, China"},{"name":"Department of Electronic Engineering, Chinese University of Hong Kong,  Hong Kong 999077, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2015,9,17]]},"reference":[{"key":"ref_1","unstructured":"WHO NCD Mortality and Morbidity. 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