{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,15]],"date-time":"2026-08-15T12:27:50Z","timestamp":1786796870900,"version":"build-2736575974"},"reference-count":42,"publisher":"IOP Publishing","issue":"9","license":[{"start":{"date-parts":[[2020,10,2]],"date-time":"2020-10-02T00:00:00Z","timestamp":1601596800000},"content-version":"vor","delay-in-days":31,"URL":"https:\/\/publishingsupport.iopscience.iop.org\/iop-standard\/v1"},{"start":{"date-parts":[[2020,10,2]],"date-time":"2020-10-02T00:00:00Z","timestamp":1601596800000},"content-version":"tdm","delay-in-days":31,"URL":"https:\/\/iopscience.iop.org\/info\/page\/text-and-data-mining"}],"funder":[{"name":"National Science Foundation","award":["(SCH-INT) 1418497"],"award-info":[{"award-number":["(SCH-INT) 1418497"]}]}],"content-domain":{"domain":["iopscience.iop.org"],"crossmark-restriction":false},"short-container-title":["Physiol. Meas."],"published-print":{"date-parts":[[2020,9,1]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:p>\n                    <jats:italic>Objective<\/jats:italic>\n                    : As the global burden of cardiovascular disease increases, proactive cardiovascular healthcare by means of accurate, precise, continuous, and non-invasive monitoring is becoming crucial. However, no current device is able to provide cardiac hemodynamic monitoring with the aforementioned criterion. Electrical impedance tomography (EIT) is an inexpensive, non-invasive imaging modality that can provide real-time images of internal conductivity distributions that describe physiological activity. This work explores and compares a standard approach of regular cardiac gated averaging (RCGA) and a newly developed method, cardiac eigen-imaging (CEI), based on the singular value decomposition (SVD) to isolate cardiac activity in thoracic EIT.\n                    <jats:italic>Approach<\/jats:italic>\n                    : EIT and heart-rate (HR) data were collected from 20 heart-failure patients preceding echocardiography. Features from RCGA and CEI images were correlated with stroke volume (SV) from echocardiography and image reconstruction parameters were optimized using leave-one-out (LOO) cross-validation.\n                    <jats:italic>Main results<\/jats:italic>\n                    : CEI per-pixel-based features achieved a Pearson correlation coefficient of 0.80 with SV relative to 0.72 with RCGA. CEI had 33 high-correlating pixels while RCGA had 8. High-correlating pixels tend to concentrate in the right-ventricle (RV) when referenced to a general chest model.\n                    <jats:italic>Significance<\/jats:italic>\n                    : While both RCGA and CEI images had high-correlating pixels, CEI had higher correlations, a larger number of high-correlating pixels, and unlike RCGA is not dependent on the quality of the HR data collected. The observed performance of the CEI approach represents a promising step forward for EIT-based cardiac monitoring in either clinical or ambulatory settings.\n                  <\/jats:p>","DOI":"10.1088\/1361-6579\/abb141","type":"journal-article","created":{"date-parts":[[2020,8,21]],"date-time":"2020-08-21T18:15:18Z","timestamp":1598033718000},"page":"095008","update-policy":"https:\/\/doi.org\/10.1088\/crossmark-policy","source":"Crossref","is-referenced-by-count":5,"title":["Cardiac eigen imaging: a novel method to isolate cardiac activity in thoracic electrical impedance tomography"],"prefix":"10.1088","volume":"41","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-6506-357X","authenticated-orcid":false,"given":"Saaid H","family":"Arshad","sequence":"first","affiliation":[{"name":"Thayer School of Engineering at Dartmouth College"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4635-3384","authenticated-orcid":false,"given":"Ethan K","family":"Murphy","sequence":"additional","affiliation":[{"name":"Thayer School of Engineering at Dartmouth College"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Joshua M","family":"Callahan","sequence":"additional","affiliation":[{"name":"Echocardiography, Dartmouth-Hitchcock Medical Center (DHMC)"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"James T","family":"DeVries","sequence":"additional","affiliation":[{"name":"Cardiac Catheterization Laboratories, DHMC"},{"name":"Geisel School of Medicine at Dartmouth"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kofi M","family":"Odame","sequence":"additional","affiliation":[{"name":"Thayer School of Engineering at Dartmouth College"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ryan J","family":"Halter","sequence":"additional","affiliation":[{"name":"Thayer School of Engineering at Dartmouth College"},{"name":"Geisel School of Medicine at Dartmouth"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"266","published-online":{"date-parts":[[2020,10,2]]},"reference":[{"key":"pmeaabb141bib1","doi-asserted-by":"publisher","first-page":"214","DOI":"10.1186\/cc9996","type":"journal-article","article-title":"Cardiac output monitoring: an integrative perspective","volume":"15","author":"Alhashemi","year":"2011","journal-title":"Crit. 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All rights, including for text and data mining, AI training, and similar technologies, are reserved.","name":"copyright_information","label":"Copyright Information"},{"value":"2020-03-30","name":"date_received","label":"Date Received","group":{"name":"publication_dates","label":"Publication dates"}},{"value":"2020-08-21","name":"date_accepted","label":"Date Accepted","group":{"name":"publication_dates","label":"Publication dates"}},{"value":"2020-10-02","name":"date_epub","label":"Online publication date","group":{"name":"publication_dates","label":"Publication dates"}}]}}