An Effective Method of Detecting Characteristic Points of Impedance Cardiogram Verified in the Clinical Pilot Study
Abstract
:1. Introduction
2. Materials and Method
2.1. Bioimpedance Cardiography Method
2.2. Hemodynamic Parameter Calculation
 ${\left(\frac{dZ}{dt}\right)}_{max}$ denotes the amplitude of the systolic wave defined as the difference between values of the B and C points marked on the ICG signal;
 VET stands for the ventricular ejection time associated with the time between the occurrence of the B and X points.
 $W\phantom{\rule{0.277778em}{0ex}}\left[\mathrm{kg}\right]$ and $H\phantom{\rule{0.277778em}{0ex}}\left[\mathrm{cm}\right]$ is the weight and height of a subject;
 $(\frac{dZ}{dt}{)}_{max}$ is the peak amplitude of the ICG signal;
 $VET$ denotes the ventricular ejection time.
2.3. The Algorithm of Identification of the Characteristic Points Implemented in the 4hearts AMULET System
2.4. The 4hearts AMULET Software
 Heart rate (HR);
 Stroke volume (SV) (defined in Equation (2));
 Cardiac output (CO) (defined in Equation (4));
 Preejection period (PEP) defined as the time between electrical systole (Q point in ECG) and the opening of the aortic valve (B point in ICG);
 Ventricular ejection time (VET) associated with the time interval between B and X point;
 Thoracic fluid content (TFC) indicates the total fluid volume of the thorax and is derived from the inverse of the base impedance ($1/{Z}_{0}$).
3. Results and Discussion
Limitations
4. Conclusions
5. Patents
Author Contributions
Funding
Institutional Review Board Statement
Informed Consent Statement
Data Availability Statement
Acknowledgments
Conflicts of Interest
References
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Fiducial Point  Physiological Significance  ICG Signal Characteristics  ECG and REO Signal Characteristics 

B 



C 



X 



N  $\mathbf{\Delta}\mathit{B}$  $\mathit{\sigma}(\mathbf{\Delta}\mathit{B})$  $\mathbf{\Delta}\mathit{C}$  $\mathit{\sigma}(\mathbf{\Delta}\mathit{C})$  $\mathbf{\Delta}\mathit{X}$  $\mathit{\sigma}(\mathbf{\Delta}\mathit{X})$  $\mathbf{\Delta}\mathbf{VET}$  $\mathit{\sigma}(\mathbf{\Delta}\mathbf{VET})$  $\mathbf{\Delta}{\mathit{A}}_{\mathbf{max}}$  $\mathit{\sigma}(\mathbf{\Delta}{\mathit{A}}_{\mathbf{max}})$ 

1  6  4  2  2  12  20  8  10  0.37  0.33 
2  18  12  2  2  4  4  10  6  0.74  0.3 
3  10  6  2  2  4  2  4  4  0.32  0.28 
f4  6  4  4  2  4  4  4  2  0.42  0.27 
5  2  2  2  2  4  4  2  2  0.03  0.03 
f6  6  6  2  2  4  4  4  2  0.09  0.08 
f7  4  4  2  4  4  2  2  2  0.07  0.05 
8  12  6  2  2  4  4  4  2  0.84  0.42 
9  18  2  2  0  2  2  10  2  2.32  0.56 
10  50  2  0  0  2  0  26  2  1.14  0.13 
11  2  2  2  2  10  14  6  8  0.05  0.03 
12  36  2  2  2  2  2  18  2  0.88  0.2 
13  22  28  2  2  0  0  12  14  0.05  0.06 
14  14  10  0  0  2  2  8  6  0.12  0.07 
15  16  10  2  2  2  2  8  4  0.5  0.3 
16  2  2  2  2  2  2  2  2  0.01  0.16 
17  42  2  2  2  2  2  22  2  0.57  0.17 
18  22  6  4  4  4  2  10  2  0.4  0.14 
19  2  2  2  2  2  2  2  2  0.07  0.16 
20  14  6  2  2  4  2  6  4  0.6  0.18 
21  8  6  2  2  16  16  6  6  0.26  0.13 
22  12  6  2  2  4  2  4  2  0.35  0.2 
23  48  42  2  2  12  8  22  18  0.27  0.2 
24  20  4  2  2  2  2  10  2  0.75  0.18 
25  56  4  4  4  14  18  36  10  1.05  0.35 
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Karpiel, I.; RichterLaskowska, M.; Feige, D.; Gacek, A.; Sobotnicki, A. An Effective Method of Detecting Characteristic Points of Impedance Cardiogram Verified in the Clinical Pilot Study. Sensors 2022, 22, 9872. https://doi.org/10.3390/s22249872
Karpiel I, RichterLaskowska M, Feige D, Gacek A, Sobotnicki A. An Effective Method of Detecting Characteristic Points of Impedance Cardiogram Verified in the Clinical Pilot Study. Sensors. 2022; 22(24):9872. https://doi.org/10.3390/s22249872
Chicago/Turabian StyleKarpiel, Ilona, Monika RichterLaskowska, Daniel Feige, Adam Gacek, and Aleksander Sobotnicki. 2022. "An Effective Method of Detecting Characteristic Points of Impedance Cardiogram Verified in the Clinical Pilot Study" Sensors 22, no. 24: 9872. https://doi.org/10.3390/s22249872