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Cited by 111Phonocardiography and Auscultation TechniquesNon-Invasive Vital Sign MonitoringECG Monitoring and Analysis

The DOI matches its Crossref record; 26 of the 27 references it cites were found in a registry or an index.

Definition of Fiducial Points in the Normal Seismocardiogram

Open access
Sørensen, Kasper, Schmidt, Samuel E., Jensen, Ask S., Søgaard, Peter, Struijk, Johannes J.·2018·Scientific Reports
DOI 10.1038/s41598-018-33675-6PMC PMC6193995
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Abstract

The purpose of this work is to define fiducial points in the seismocardiogram (SCG) and to correlate them with physiological events identified in ultrasound images. For 45 healthy subjects the SCG and the electrocardiogram (ECG) were recorded simultaneously at rest. Immediately following the SCG and ECG recordings ultrasound images of the heart were also obtained at rest. For all subjects a mean SCG signal was calculated and all fiducial points (peaks and valleys) were identified and labeled in the same way across all signals. Eight physiologic events, including the valve openings and closings, were annotated from ultrasound as well and the fiducial points were correlated with those physiologic events. A total of 42 SCG signals were used in the data analysis. The smallest mean differences (±SD) between the eight events found in the ultrasound images and the fiducial points, together with their correlation coefficients (r) were: atrial systolic onset: −2 (±16) ms, r = 0.75 (p < 0.001); peak atrial inflow: 13 (±19) ms, r = 0.63 (p < 0.001); mitral valve closure: 4 (±11) ms, r = 0.71 (p < 0.01); aortic valve opening: −3 (±11) ms, r = 0.60 (p < 0.001); peak systolic outflow: 13 (±23) ms, r = 0.42 (p < 0.01); aortic valve closure: −5 (±12) ms, r = 0.94 (p < 0.001); mitral valve opening: −7 (±19) ms, r = 0.87 (p < 0.001) and peak early ventricular filling: −18 (±28 ms), r = 0.79 (p < 0.001). In conclusion eight physiologic events characterizeing the cardiac cycle, are associated with reproducible, well-defined fiducial points in the SCG.

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Crossref · 10.1038/s41598-018-33675-6

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Figures

Figure 1 A seismocardiographic signal from one subject aligned to the ECG R-peak (systolic complex) and to the diastolic complex respectively. Individual beats are plotted in grey, the mean beats are plotted in black.
Figure 1 A seismocardiographic signal from one subject aligned to the ECG R-peak (systolic complex) and to the diastolic complex respectively. Individual beats are plotted in grey, the mean beats are plotted in black.CC BY · PubMed Central
Figure 2 SCG signals from subject 09 (A), 15 (B) and 22 (C) with labeling of the fiducial points in the two complexes.
Figure 2 SCG signals from subject 09 (A), 15 (B) and 22 (C) with labeling of the fiducial points in the two complexes.CC BY · PubMed Central
Figure 3 Correlation plots for the fiducial points and ultrasound images listed in Table 6.
Figure 3 Correlation plots for the fiducial points and ultrasound images listed in Table 6.CC BY · PubMed Central
Figure 4 Overall mean electrocardiogram and seismocardiogram signal from 34 subjects. The circles indicate the mean location of the following physiologic events found in ultrasound images, from left: Atrial systole (AS), peak atrial inflow (PAI), mitral valve closure (MC), aortic valve opening (AO), peak systolic inflow (PSI), aortic valve closing (AC), mitral valve opening (MO), early ventricular filling (EVF). The grey areas indicate the 95% confidence intervals of the means for the physiologic events found in the ultrasound images.
Figure 4 Overall mean electrocardiogram and seismocardiogram signal from 34 subjects. The circles indicate the mean location of the following physiologic events found in ultrasound images, from left: Atrial systole (AS), peak atrial inflow (PAI), mitral valve closure (MC), aortic valve opening (AO), peak systolic inflow (PSI), aortic valve closing (AC), mitral valve opening (MO), early ventricular filling (EVF). The grey areas indicate the 95% confidence intervals of the means for the physiologic events found in the ultrasound images.CC BY · PubMed Central

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Citations

Cites

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Research works printed but not linked: 2

  1. Baevsky, R., Egorov, A. & Kazarian, L. Metodika seismokardiografii. Kardiologia 18, 87–89 (1964).
  2. Otto, Catherine M. Textbook of Clinical Echocardiography: Expert Consult - Online and Print, 4e. (Saunders, 2009).

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Metadata

Authors
Sørensen, K., Schmidt, S. E., Jensen, A. S., Søgaard, P., & Struijk, J. J.
Affiliations
  • Aalborg University (DK)
  • Aalborg University Hospital (DK)
Corresponding author
Sørensen, Kasper
ORCID
Venue
Scientific Reports
Publisher
Springer Science and Business Media LLC
Published
2018-10-18
Volume
8
Issue
1
Pages
15455-15455
ISSN
2045-2322 (ISSN-L)
DOI
10.1038/s41598-018-33675-6
PMC
PMC6193995
OpenAlex
W2896674935
Cited by
111
References
27
Citations by year
2026: 13 · 2025: 17 · 2024: 8 · 2023: 14 · 2022: 20 · 2021: 11 · 2020: 22 · 2019: 6
FWCI
7.35
Type
journal article
Language
en
Update notices
correction (2020-09-04)
Open access
Licence
Locations
  • Scientific Reports (publishedVersion, cc-by)
  • Europe PMC (PubMed Central) (publishedVersion, other-oa)
  • PubMed Central (publishedVersion, cc-by)
  • PubMed (publishedVersion)
  • VBN Forskningsportal (Aalborg Universitet) (publishedVersion, cc-by)
  • DOAJ (DOAJ: Directory of Open Access Journals) (submittedVersion)
Topics
  • Health Sciences › Medicine › Pulmonary and Respiratory Medicine › Phonocardiography and Auscultation Techniques
  • Physical Sciences › Engineering › Biomedical Engineering › Non-Invasive Vital Sign Monitoring
  • Health Sciences › Medicine › Cardiology and Cardiovascular Medicine › ECG Monitoring and Analysis
Keywords
seismocardiogram, fiducial points, mitral valve closure, aortic valve closure, valve opening, echocardiography, electrocardiogram
MeSH terms
Adult, Aged, Aged, 80 and over, Diastole, Echocardiography, Electrocardiography, Heart Function Tests, Heart Valves, Humans, Image Processing, Computer-Assisted, Middle Aged, Myocardial Contraction, Reference Values, Signal Processing, Computer-Assisted, Systole, Vibration, Reproducibility of Results, Young Adult, Fiducial Markers, Accelerometry

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