• The Journal of Korean Obstetrics and Gynecology
• /
• v.24 no.3
• /
• pp.109-115
• /
• 2011

Objectives: To characterize autonomic dysfunction in patients with Cold hypersensitivity, their heart rate variability(HRV) were measured and analyzed with cold hypersensitivity patients, compared with those of normal population. Methods: We studied 56 patients visiting Gangnam Kyung-hee korean hospital from 1st January 2010 to 31th December 2010. Heart rate variability were obtained from 28 female patients who suffer from cold hypersensitivity and 28 healthy female controls in resting state. We studied the difference of Heart rate variability between two groups by Independent T-test using SPSS for windows(version 17.0). Results: Standard deviation of NN interval(SDNN), total power(TP), Very low frequency(VLF) in patients with cold hypersensitivity were significantly different with those of controls. While no significant differences were observed in square root of mean squared differences of successive NN intervals (RMSSD), low frequency (LF) and high frequency(HF). Conclusions: The decreased values of heart rate variability(HRV) study means that they may have some kinds of imbalance in autonomic nervous system in cold hypersensitivity patients. heart rate variabiliry(HRV) study might be a tool of diagnosis and predictors in cold hypersensitivity patients.

• International conference on construction engineering and project management
• /
• 2020.12a
• /
• pp.257-264
• /
• 2020

Objective: To investigate test-retest reliability and responsiveness of Equivital Lifemonitor and photoplethysmography based wristwatch tools in assessing physiological parameters during a simulated fatigue task. Methods: Ten university students (Mean age, 30.6 ± 1.7 years) participated in this pilot study. Participants were asked to perform a 30-minute of a simulated fatigue task in an experimental setup in a lab. The physiological parameters (e.g., heart rate, heart rate variability, respiratory rate, electrodermal activity, and skin temperature) were measured at baseline and immediately after the fatigue task. An intraclass correlation coefficient (ICC2,1) was used to evaluate the test-retest reliability of each tool in assessing physiological measures. In addition, the responsiveness of each tool to measure changes from baseline to posttest was calculated using a standardized response mean. Results: The Equivital Lifemonitor has shown good to excellent test-retest reliability for the assessment of heart rate (ICC, 0.97), heart rate variability (ICC, 0.86), respiratory rate (ICC, 0.77), and local skin temperature (ICC, 0.76). However, photoplethysmography based wristwatch showed moderate to good test-retest reliability for the assessment of heart rate (ICC, 0.71), heart rate variability (ICC, 0.73), electrodermal activity (ICC, 0.80), and skin temperature (ICC, 0.72). A large standardized response mean (>0.8) indicates that both tools can capture the changes in heart rate, heart rate variability, respiratory rate, skin temperature, and electrodermal activity after a 30-minute of fatigue task. Conclusions: The Equivital Lifemonitor and photoplethysmography based wristwatch devices are reliable in measuring physiological parameters after the fatigue task. Additionally, both devices can capture the fatigue response after a simulated construction task. Future field studies with a larger sample should investigate the sensitivity and validity of these tools in measuring physiological parameters for fatigue assessment at construction sites.

• Stress
• /
• v.26 no.4
• /
• pp.305-311
• /
• 2018

Background: The purpose of the study was to explore whether the effect of Huanglian-jie-du granule depends on the baseline heart rate variability in patients with Hwa-byung. Methods: We used the supplementary data from a randomized, double-blind, placebo-controlled trial of Huanglian-jie-du granule for Hwa-byung patients. Study drugs were taken orally three times per day for one week. Heart rate variability was measured three times; before the treatment, after the treatment, and month follow-up period. Spearman's rho test was done to explore the role of the baseline heart rate variability to the effect of Huanglian-jie-du granule. Results: Baseline low frequency power of heart rate variability was negatively correlated with the reduction of the insomnia severity index in experimental group (r=-0.493 p=0.02). Also, Huanglian-jie-de granule significantly decreased the low frequency power of heart rate variability in patients with Hwa-byung compared to placebo (mean difference 266 [95% CI: 29~503], p=0.028). In Hwa-byung symptoms, stuffy, pushing up in the chest, and flush of anger were correlated with low frequency power of heart rate variability (p=0.010, p=0.000, and p=0.016, respectively). Conclusions: The effect of the Huanglian-jie-de granule for insomnia seems to be lower when the baseline low frequency power of heart rate variability is higher in Hwa-byung patients. Also, Huanglian-jie-de granule is likely to decrease the sympathetic activity in patients with Hwa-byung. Measurement of heart rate variability may be the useful to understand the state of Hwa-byung patients.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2007.06a
• /
• pp.323-324
• /
• 2007

• Journal of Biomedical Engineering Research
• /
• v.39 no.2
• /
• pp.87-93
• /
• 2018

The measurement of Heart Rate Variability (HRV) using electrocardiogram (ECG) signals has been used to predict fatigue and stress levels in a clinical environment, yet, owing to the complexity of such ECG systems, a domestic, nonclinical monitoring of HRV has not been a practical possibility. Recently though, Pulse Rate Variability (PRV) has been studied as an alternative to HRV. In this study, we investigated the reliability of measuring PRV by means of a smartwatch. The PRV results were compared to HRV results in similar test conditions, i.e. those obtained under rapid and deep-breathing scenarios. From the results obtained, it transpires that the Bland-Altman ratio and cross-correlation coefficients between several PRV and HRV parameters were highly correlated, thus suggesting that the results of measuring PRV using a smartwatch can be used to predict HRV in nonclinical environments.

• Proceedings of the KOSOMBE Conference
• /
• v.1994 no.12
• /
• pp.169-171
• /
• 1994

This paper is to find out more reliable analyzing method of heart rate variability. Heart rate variability analysis is to evaluate cardiovascular stability and also have used as an indicator of autonomic nervous system activity. In this study, time domain analysis, spectral analysis and state space analysis method are applied to analyze heart rate variability. Because of nonlinear characteristics of heart rate, we need not only spectral analysis, but also state space analysis. Fractal dimension of spectral estimation is useful indicator of autonomic nervous activity.

• Annals of Clinical Neurophysiology
• /
• v.16 no.2
• /
• pp.49-54
• /
• 2014

Heart rate variability is significantly associated with cardiovascular complications in various neurological disorders with cardiac impairment. Measures of spontaneous heart rate variability might be different from provocating tests of heart rate variability such as deep breathing and Valsava maneuver. Methods for analysis are divided into time domain methods and frequency domain methods. There are standard deviation of NN interval, standard deviation of average NN interval, root mean square of the successive differences, NN50, and pNN50 in time domain methods. Frequency domain bands can be divided into very low, low, and high frequency. Each variables are influenced by sympathetic and/or parasympathetic activity.

• Child Health Nursing Research
• /
• v.21 no.3
• /
• pp.195-203
• /
• 2015

Purpose: This study was done to investigate quality of sleep and heart rate variability by the physical activity in high school students. Methods: A survey that measures physical activity and quality of sleep was distributed to 118 students at Y High School. Heart rate variability was obtained using the LXC3203 heart rate monitor. The data of 105 students were analyzed using descriptive statistics, t-test, x2-test, and ANOVA with $Scheff{\acute{e}}$ test. Results: Boys and students with part-time jobs had significantly higher physical activity. The quality of sleep was significantly high when the students were non-smokers, felt healthy, happy, less stressed, and satisfied with their school lives. Mean heart rate was significantly higher among girls, and standard deviation from normal to normal R-R intervals were high in boys. Physical activity had no significant relationships with quality of sleep and heart rate variability. Conclusions: Physical activity should be encouraged for high school students, especially for girls. An experimental study with different intensity and time of physical activity is recommended to examine the relationships with quality of sleep and heart rate variability in the future.

• Journal of the Korea Convergence Society
• /
• v.11 no.4
• /
• pp.49-54
• /
• 2020

The purpose of this study was to investigate the correlation between sports incidence and heart rate variability in nationa lfemale judo athletes. Participants measured heart rate variability using the Autonomic Nervous System(SA-6000). Based on the average incidence of injury, sports injury incidence was classified into upper and lower groups. In addition, Pearson's Product Moment Correlation was performed to examine the correlation between the independent T-test, the number of sports injuries, and the heart rate variability. Heart rate variability was significantly different in total power and low frequency, and there was also significant difference in otal power and low frequency in the correlation analysis of heart rate variability according to the number of sports injuries. These data are expected to be useful as basic data for developing prevention injury programs.

• Journal of Korean Academy of Nursing
• /
• v.41 no.6
• /
• pp.788-794
• /
• 2011

Purpose: Reduced heart rate variability significantly increases cardiovascular mortality. Metabolic syndrome increases the cardiac autonomic dysfunction. Recently, increasing cardiovascular mortality has been reported in patients with schizophrenia. This study was done to compare heart rate variability between adults with and without schizophrenia and to compare the relationship of heart rate variability to metabolic syndrome in hospitalized patients with schizophrenia. Methods: This was a descriptive and correlational study in which 719 adults without schizophrenia and 308 adults with schizophrenia took part between May and June 2008. We measured the following: five-minute heart rate variability; high-frequency, low-frequency, the ratio of low-frequency to high-frequency, and the Standard Deviation of all the normal RR intervals. Data was also collected on metabolic syndrome, abdominal obesity, triglycerides, HDL cholesterol, blood pressure and fasting glucose. Results: The Standard Deviation of all the normal RR intervals values of heart rate variability indices were $1.53{\pm}0.18$. The low-frequency and high-frequency values of heart rate variability indices were significantly higher in hospitalized patients with schizophrenia ($3.89{\pm}1.36$; $3.80{\pm}1.20$) than those in the healthy participants ($2.20{\pm}0.46$; $2.10{\pm}0.46$). There were no significant differences between the schizophrenic patients with and without metabolic syndrome. Conclusion: The results of this study indicate that schizophrenia patients have significantly lower cardiac autonomic control, but they have significantly higher low-frequency and high-frequency values than those of healthy adults. Use of antipsychotic drug may affect the autonomic nervous system in schizophrenic patients. Metabolic syndrome was not associated with cardiac autonomic control in schizophrenia patients.