{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,18]],"date-time":"2026-06-18T09:50:47Z","timestamp":1781776247506,"version":"3.54.5"},"reference-count":68,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2023,2,16]],"date-time":"2023-02-16T00:00:00Z","timestamp":1676505600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"European Regional Development Fund","award":["01.2.2-LMT-K-718-03-0027"],"award-info":[{"award-number":["01.2.2-LMT-K-718-03-0027"]}]},{"name":"European Regional Development Fund","award":["FS\/20\/20\/34626"],"award-info":[{"award-number":["FS\/20\/20\/34626"]}]},{"name":"British Heart Foundation (BHF)","award":["01.2.2-LMT-K-718-03-0027"],"award-info":[{"award-number":["01.2.2-LMT-K-718-03-0027"]}]},{"name":"British Heart Foundation (BHF)","award":["FS\/20\/20\/34626"],"award-info":[{"award-number":["FS\/20\/20\/34626"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Intervals of low-quality photoplethysmogram (PPG) signals might lead to significant inaccuracies in estimation of pulse arrival time (PAT) during polysomnography (PSG) studies. While PSG is considered to be a \u201cgold standard\u201d test for diagnosing obstructive sleep apnea (OSA), it also enables tracking apnea-related nocturnal blood pressure fluctuations correlated with PAT. Since the electrocardiogram (ECG) is recorded synchronously with the PPG during PSG, it makes sense to use the ECG signal for PPG signal-quality assessment. (1) Objective: to develop a PPG signal-quality assessment algorithm for robust PAT estimation, and investigate the influence of signal quality on PAT during various sleep stages and events such as OSA. (2) Approach: the proposed algorithm uses R and T waves from the ECG to determine approximate locations of PPG pulse onsets. The MESA database of 2055 PSG recordings was used for this study. (3) Results: the proportions of high-quality PPG were significantly lower in apnea-related oxygen desaturation (matched-pairs rc = 0.88 and rc = 0.97, compared to OSA and hypopnea, respectively, when p &lt; 0.001) and arousal (rc = 0.93 and rc = 0.98, when p &lt; 0.001) than in apnea events. The significantly large effect size of interquartile ranges of PAT distributions was between low- and high-quality PPG (p &lt; 0.001, rc = 0.98), and regular and irregular pulse waves (p &lt; 0.001, rc = 0.74), whereas a lower quality of the PPG signal was found to be associated with a higher interquartile range of PAT across all subjects. Suggested PPG signal quality-based PAT evaluation reduced deviations (e.g., rc = 0.97, rc = 0.97, rc = 0.99 in hypopnea, oxygen desaturation, and arousal stages, respectively, when p &lt; 0.001) and allowed obtaining statistically larger differences between different sleep stages and events. (4) Significance: the implemented algorithm has the potential to increase the robustness of PAT estimation in PSG studies related to nocturnal blood pressure monitoring.<\/jats:p>","DOI":"10.3390\/s23042220","type":"journal-article","created":{"date-parts":[[2023,2,16]],"date-time":"2023-02-16T04:01:52Z","timestamp":1676520112000},"page":"2220","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":10,"title":["Influence of Photoplethysmogram Signal Quality on Pulse Arrival Time during Polysomnography"],"prefix":"10.3390","volume":"23","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-0989-3023","authenticated-orcid":false,"given":"Mantas","family":"Rinkevi\u010dius","sequence":"first","affiliation":[{"name":"Biomedical Engineering Institute, Kaunas University of Technology, K. Bar\u0161ausko Str. 59, LT-51423 Kaunas, Lithuania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3836-8655","authenticated-orcid":false,"given":"Peter H.","family":"Charlton","sequence":"additional","affiliation":[{"name":"Department of Public Health and Primary Care, University of Cambridge, Cambridge CB2 1TN, UK"},{"name":"Research Centre for Biomedical Engineering, University of London, London WC1E 7HU, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1272-0550","authenticated-orcid":false,"given":"Raquel","family":"Bail\u00f3n","sequence":"additional","affiliation":[{"name":"Biomedical Signal Interpretation and Computational Simulation (BSICoS) Group, Aragon Institute of Engineering Research (I3A), IIS Aragon, University of Zaragoza, 50009 Zaragoza, Spain"},{"name":"Biomedical Research Networking Center (CIBER), 50018 Zaragoza, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6879-5845","authenticated-orcid":false,"given":"Vaidotas","family":"Marozas","sequence":"additional","affiliation":[{"name":"Biomedical Engineering Institute, Kaunas University of Technology, K. Bar\u0161ausko Str. 59, LT-51423 Kaunas, Lithuania"},{"name":"Faculty of Electrical and Electronics Engineering, Kaunas University of Technology, Student\u0173 Str. 50, LT-51368 Kaunas, Lithuania"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2023,2,16]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"21","DOI":"10.1007\/s13534-019-00097-w","article-title":"Current progress of photoplethysmography and SPO2 for health monitoring","volume":"9","author":"Tamura","year":"2019","journal-title":"Biomed. Eng. Lett."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"R1","DOI":"10.1088\/0967-3334\/28\/3\/R01","article-title":"Photoplethysmography and its application in clinical physiological measurement","volume":"28","author":"Allen","year":"2007","journal-title":"Physiol. 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