scholarly journals Textile-Friendly Interconnection between Wearable Measurement Instrumentation and Sensorized Garments—Initial Performance Evaluation for Electrocardiogram Recordings

Sensors ◽  
2019 ◽  
Vol 19 (20) ◽  
pp. 4426 ◽  
Author(s):  
Fernando Seoane ◽  
Azadeh Soroudi ◽  
Ke Lu ◽  
David Nilsson ◽  
Marie Nilsson ◽  
...  

The interconnection between hard electronics and soft textiles remains a noteworthy challenge in regard to the mass production of textile–electronic integrated products such as sensorized garments. The current solutions for this challenge usually have problems with size, flexibility, cost, or complexity of assembly. In this paper, we present a solution with a stretchable and conductive carbon nanotube (CNT)-based paste for screen printing on a textile substrate to produce interconnectors between electronic instrumentation and a sensorized garment. The prototype connectors were evaluated via electrocardiogram (ECG) recordings using a sensorized textile with integrated textile electrodes. The ECG recordings obtained using the connectors were evaluated for signal quality and heart rate detection performance in comparison to ECG recordings obtained with standard pre-gelled Ag/AgCl electrodes and direct cable connection to the ECG amplifier. The results suggest that the ECG recordings obtained with the CNT paste connector are of equivalent quality to those recorded using a silver paste connector or a direct cable and are suitable for the purpose of heart rate detection.

2021 ◽  
Vol 2 ◽  
Author(s):  
Katherine Le ◽  
Amir Servati ◽  
Saeid Soltanian ◽  
Peyman Servati ◽  
Frank Ko

Electronic textile (e-textile) systems applied to biological signal monitoring are of great interest to the healthcare industry, given the potential to provide continuous and long-term monitoring of healthy individuals and patients. Most developments in e-textiles have focused on novel materials and systems without systematic considerations into how the hierarchical structure of fibrous assemblies may influence performance and compatibility of the materials during use. This study examines mechanisms underlying the stability and quality of textile-based electrocardiogram (ECG) electrodes used in a smart bra. Signal quality of the biometric data obtained affects feedback and user experience and may be influenced by characteristics and properties of the material. Under stationary and dynamic conditions, analysis of the raw ECG signal and heart rate, with respect to textile-electrode material properties have been performed. Currently, there is no standardized procedure to compare the ECG signal between electrode materials. In this study, several methods have been applied to compare differences between silver-based textile electrodes and silver/silver-chloride gel electrodes. The comparison methods serve to complement visual observations of the ECG signal acquired, as possible quantitative means to differentiate electrode materials and their performance. From the results obtained, signal quality, and heart rate (HR) detection were found to improve with increased skin contact, and textile structures with lower stretch and surface resistance, especially under dynamic/movement test conditions. It was found that the performance of the textile electrode materials compared exceeded ECG signal quality thresholds previously established for acceptable signal quality, specifically for the kurtosis (K > 5), and Pearson correlation coefficients (r ≥ 0.66) taken from average ECG waveforms calculated.


2021 ◽  
Vol 4 (1) ◽  
Author(s):  
Elisa Mejía-Mejía ◽  
James M. May ◽  
Mohamed Elgendi ◽  
Panayiotis A. Kyriacou

AbstractHeart rate variability (HRV) utilizes the electrocardiogram (ECG) and has been widely studied as a non-invasive indicator of cardiac autonomic activity. Pulse rate variability (PRV) utilizes photoplethysmography (PPG) and recently has been used as a surrogate for HRV. Several studies have found that PRV is not entirely valid as an estimation of HRV and that several physiological factors, including the pulse transit time (PTT) and blood pressure (BP) changes, may affect PRV differently than HRV. This study aimed to assess the relationship between PRV and HRV under different BP states: hypotension, normotension, and hypertension. Using the MIMIC III database, 5 min segments of PPG and ECG signals were used to extract PRV and HRV, respectively. Several time-domain, frequency-domain, and nonlinear indices were obtained from these signals. Bland–Altman analysis, correlation analysis, and Friedman rank sum tests were used to compare HRV and PRV in each state, and PRV and HRV indices were compared among BP states using Kruskal–Wallis tests. The findings indicated that there were differences between PRV and HRV, especially in short-term and nonlinear indices, and although PRV and HRV were altered in a similar manner when there was a change in BP, PRV seemed to be more sensitive to these changes.


Author(s):  
Tsu-Wang Shen ◽  
Shan-Chun Chang

Abstract Purpose Although electrocardiogram (ECG) has been proven as a biometric for human identification, applying biometric technology remains challenging with diverse heart rate circumstances in which high intensity heart rate caused waveform deformation may not be known in advance when ECG templates are registered. Methods A calibration method that calculates the ratio of the length of an unidentified electrocardiogram signal to the length of an electrocardiogram template is proposed in this paper. Next, the R peak is used as an axis anchor point of a trigonometric projection (TP) to attain the displacement value. Finally, the unidentified ECG signal is calibrated according to the generated trigonometric value, which corresponds to the trigonometric projection degree of the ratio and the attained displacement measurement. Results The results reveal that the proposed method provides superior overall performance compared with that of the conventional downsampling method, based on the percentage root mean square difference (PRD), correlation coefficients, and mean square error (MSE). Conclusion The curve fitting equation directly maps from the heart rate levels to the TP degree without prior registration information. The proposed ECG calibration method offers a more robust system against heart rate interference when conducting ECG identification.


Sensors ◽  
2021 ◽  
Vol 21 (13) ◽  
pp. 4298
Author(s):  
Alessandra Galli ◽  
Elisabetta Peri ◽  
Yijing Zhang ◽  
Rik Vullings ◽  
Myrthe van der Ven ◽  
...  

Multi-channel measurements from the maternal abdomen acquired by means of dry electrodes can be employed to promote long-term monitoring of fetal heart rate (fHR). The signals acquired with this type of electrode have a lower signal-to-noise ratio and different artifacts compared to signals acquired with conventional wet electrodes. Therefore, starting from the benchmark algorithm with the best performance for fHR estimation proposed by Varanini et al., we propose a new method specifically designed to remove artifacts typical of dry-electrode recordings. To test the algorithm, experimental textile electrodes were employed that produce artifacts typical of dry and capacitive electrodes. The proposed solution is based on a hybrid (hardware and software) pre-processing step designed specifically to remove the disturbing component typical of signals acquired with these electrodes (triboelectricity artifacts and amplitude modulations). The following main processing steps consist of the removal of the maternal ECG by blind source separation, the enhancement of the fetal ECG and identification of the fetal QRS complexes. Main processing is designed to be robust to the high-amplitude motion artifacts that corrupt the acquisition. The obtained denoising system was compared with the benchmark algorithm both on semi-simulated and on real data. The performance, quantified by means of sensitivity, F1-score and root-mean-square error metrics, outperforms the performance obtained with the original method available in the literature. This result proves that the design of a dedicated processing system based on the signal characteristics is necessary for reliable and accurate estimation of the fHR using dry, textile electrodes.


2021 ◽  
Vol 167 ◽  
pp. 112283
Author(s):  
M. Fukuda ◽  
Y. Seki ◽  
K. Ezato ◽  
K. Yokoyama ◽  
H. Nishi ◽  
...  

1999 ◽  
Vol 277 (4) ◽  
pp. H1491-H1497
Author(s):  
Daniel Roach ◽  
Robert Haennel ◽  
Mary Lou Koshman ◽  
Robert Sheldon

We are developing a lexicon of specific heart period changes, or lexons, that recur frequently and whose physiological meaning can be read into ambulatory electrocardiogram (ECG). The transient, reversible “burst” of tachycardia induced by exercise initiation can also be seen on ambulatory ECG. We hypothesized that burst morphology depended on the work that preceded it and on baroreceptor activation. Ten subjects with mean age 38 yr (range 17–69 yr) underwent two protocols of semisupine cycling in which load and duration were varied. Burst duration increased with longer cycling times (median values of 18.0, 25.5, and 23.7 s with 1, 3, and 5 s of cycling, respectively; P= 0.033). Burst shape as assessed by heart period exponential decay constant and burst magnitude did not change. To assess the impact of workload, subjects cycled for 5 s at loads of 0, 25, 50, and 75 W. No significant differences were seen in burst duration, burst magnitude, or burst shape. Tachycardia preceded hypotension by 4.6 ± 2.2 s, which is inconsistent with baroreceptor involvement in the onset of burst tachycardia. Because burst morphology is a nearly quantal response to the initiation of exercise, the presence of a burst on an ambulatory ECG implies the onset of exercise.


Author(s):  
Jeremy A. Bigalke ◽  
Ian M. Greenlund ◽  
Jennifer R. Nicevski ◽  
Carl A. Smoot ◽  
Benjamin Oosterhoff ◽  
...  

Chronic insufficient sleep is a common occurrence around the world, and results in numerous physiological detriments and consequences, including cardiovascular complications. The purpose of the present study was to assess the relationship between habitual total sleep time (TST) measured objectively via at-home actigraphy and heart rate (HR) reactivity to nocturnal cortical arousals. We hypothesized that short habitual TST would be associated with exaggerated cardiac reactivity to nocturnal cortical arousals. Participants included in 35 healthy individuals (20 male, 15 female, age: 24 ± 1, BMI: 27 ± 1 kg/m2), and were split using a median analysis into short (SS; n = 17) and normal sleeping (NS; n = 18) adults based on a minimum of 7 days of at-home actigraphy testing. All participants underwent a full overnight laboratory polysomnography (PSG) testing session, including continuous HR (electrocardiogram, ECG) sampling. HR reactivities to all spontaneous cortical arousals were assessed for 20 cardiac cycles following the onset of the arousal in all participants. Baseline HR was not significantly different between groups (P > .05). Spontaneous nocturnal arousal elicited an augmented HR response in the SS group, specifically during the recovery period [F (4.192, 134.134) = 3.413, p = .01]. There were no significant differences in HR reactivity between sexes [F (4.006, 128.189) = .429, p > .05]. These findings offer evidence of nocturnal cardiovascular dysregulation in habitual short sleepers, independent from any diagnosed sleep disorders.


2000 ◽  
Vol 8 (2) ◽  
pp. 120-128
Author(s):  
Nobuo Takeshima ◽  
William F. Brechue ◽  
Setsuko Ueya ◽  
Kiyoji Tanaka

This study attempted to determine the accuracy of measuring heart rate by radial artery palpation in elderly individuals. Elderly (ELD; n = 26) and young (Y; n = 21) individuals completed 3 intensity levels of exercise on a treadmill, each carried out on a separate day. Participants determined their heart rate by palpating the radial artery (PR) after exercise. In ELD, there were significant differences between PR and electrocardiogram (ECG; p = .007). Heart-rate errors at each intensity of exercise were 7.2 ± 12.5, 6.6 ± 15.7, and 10.1 ± 16.5 beats/min. There were no differences in PR and ECG in Y. Fingertip sensitivity was significantly lower in ELD than in Y. A significant, negative correlation existed (r = -.56, n = 26) between heart-rate error and fingertip sensitivity in ELD. These data suggest that self-conducted PR by elderly individuals fails to accurately estimate heart rate. This appears to result from lessened vibrotactile sensitivity in the fingers.


2019 ◽  
Vol 18 (3) ◽  
pp. 144-147
Author(s):  
Mary Rimbi ◽  
◽  
Immaculate Nakitende ◽  
Teopista Namujwiga ◽  
John Kellett ◽  
...  

Background: heart rates generated by pulse oximeters and electronic sphygmomanometers in acutely ill patients may not be the same as those recorded by ECG Methods: heart rates recorded by an oximeter and an electronic sphygmomanometer were compared with electrocardiogram (ECG) heart rates measured on acutely ill medical patients. Results: 1010 ECGs were performed on 217 patients while they were in the hospital. The bias between the oximeter and the ECG measured heart rate was -1.37 beats per minute (limits of agreement -22.6 to 19.9 beats per minute), and the bias between the sphygmomanometer and the ECG measured heart rate was -0.14 beats per minute (limits of agreement -22.2 to 21.9 beats per minute). Both devices failed to identify more than half the ECG recordings that awarded 3 NEWS points for heart rate. Conclusion: Heart rates of acutely ill patients are not reliably measured by pulse oximeter or electronic sphygmomanometers.


Sign in / Sign up

Export Citation Format

Share Document