Effects of Heat Stress on Heart Rate Variability in Free-Moving Sheep and Goats Assessed With Correction for Physical Activity

Heart rate variability (HRV) is the heart beat-to-beat variation under control of the cardiovascular function of animals. Under stressed conditions, cardiac activity is generally regulated with an upregulated sympathetic tone and withdrawal of vagal tone; thus, HRV monitoring can be a non-invasive technique to assess stress level in animals especially related to animal welfare. Among several stress-induced factors, heat stress is one of the most serious causes of physiological damage to animals. The aim of this study was to assess the effects of heat stress on HRV in small ruminants under free-moving conditions. In three experimental periods (June, August, and October), inter-beat intervals in sheep and goats (three for each) in two consecutive days were measured. HRV parameters were calculated from the inter-beat interval data by three types of analyses: time domain, frequency domain, and non-linear analyses. The temperature–humidity index (THI) was used as an indicator of heat stress, and vectorial dynamic body acceleration (VeDBA) was calculated to quantify the physical activity of the animals tested. First, we investigated correlations of THI and VeDBA with HRV parameters; subsequently, THI was divided into five categories according to the values obtained (≤ 65, 65–70, 70–75, 75–80, and >80), and the effects of the THI categories on HRV parameters were investigated with and without correcting for the effects of physical activity based on the VeDBA. The results indicated that HRV significantly decreased with increasing THI and VeDBA. For non-linear HRV parameters that were corrected for the effects of physical activity, it was suggested that there would be a threshold of THI around 80 that strongly affected HRV; high heat stress can affect the autonomic balance of animals non-linearly by inducing the sympathetic nervous system. In conclusion, to assess psychophysiological conditions of unrestrained animals by HRV analysis, the confounding effect of physical activity on HRV should be minimized for a more precise interpretation of the results.

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Assessment of Heat Stress and Heart Rate Variability Monitoring for Foundry Workers (Preprint)

10.2196/preprints.18461 ◽

2020 ◽

Author(s):

Elayaraja R ◽

Subramaniam D Sr

Keyword(s):

Heart Rate ◽

Heart Rate Variability ◽

Heat Stress ◽

Atmospheric Temperature ◽

Heart Beat ◽

Stress Index ◽

Thermal Pressure ◽

Globe Temperature ◽

The Individual ◽

Heat Stress Index

UNSTRUCTURED - Background: Industrial employee studies the thermal pressure arises from both warm (or) cold running environment. Foundry is an arena in which metals are melted and casted with producing extensive quantity of heat. The temperature is in crescendo due to very high melting temperature and fallacious ventilation. Due to those hot foundry environments, the beat of coronary heart fee of the individual will range due to difference in temperature of skin and atmospheric temperature. Objective: This paper specializes in parameters and elements which might be used to symbolize thermal pressure and to evaluate the warmth pressure of foundry employees using Heat Stress Index (H.S.I) and Wet Bulb Globe Temperature (WBGT) also to monitor the coronary heart rate variability of foundry people. Methods: H.S.I studying became cited to get entry to on foundry. The readings along with velocity of air (Vair), dry bulb temperature (Ta) and moist bulb temperature of air (Tn) had been recorded at 5 extraordinary employee positions for the duration of melting and pouring operations in the foundry. The coronary heart price was recorded the use of heart rate monitoring device in melting and pouring sections of foundry. Results: The two different indices particularly H.S.I and WBGT are considered for decided on workplace. The have a look at discovered a higher H.S.I score of 30.36 while pouring molten metallic from furnace to ladle, in melting segment and reduced by using increasing the speed of air to 23.25 which indicates 23.Four% of warmth from the surroundings decreased is an appropriate H.S.I score consistent with Belding & Hatch Heat Stress Index. As consistent with the ACGIH recommendations, the WBGT index is falling underneath the scheme of 25% paintings and 75% relaxation regimen. The most heart beat fee turned into 159bpm even as pouring molten steel from ladle to mould box and the most coronary heart beat price became 135bpm for the duration of loading of metallic strips into the furnace. The hazard factors may be analyzed in the decided on segment of foundry. Conclusion: Thermal pressure from furnace can be reduced by using installing a non- emissive warmness protect among furnace and employee, with the aid of providing protecting device, by growing velocity of air and with the aid of automating the pouring operation. Insulating reduces the heat exchange among the supply of warmth and the ambience temperature. The attention of lowering humidity like dehumidification, aircon and elimination of open hot furnace, leaky steam valves allows to lessen humidity. Recommendations may be suggested to adjust the posture of foundry people as a way to lessen the coronary heart charge.

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Non-linear Methods Predominant in Fetal Heart Rate Analysis: A Systematic Review

Frontiers in Medicine ◽

10.3389/fmed.2021.661226 ◽

2021 ◽

Vol 8 ◽

Author(s):

Maria Ribeiro ◽

João Monteiro-Santos ◽

Luísa Castro ◽

Luís Antunes ◽

Cristina Costa-Santos ◽

...

Keyword(s):

Heart Rate ◽

Signal Processing ◽

Heart Rate Variability ◽

Fetal Heart Rate ◽

Fetal Heart ◽

Linear Method ◽

Cardiac Activity ◽

Well Being ◽

Non Linear ◽

Fetal Heart Rate Variability

The analysis of fetal heart rate variability has served as a scientific and diagnostic tool to quantify cardiac activity fluctuations, being good indicators of fetal well-being. Many mathematical analyses were proposed to evaluate fetal heart rate variability. We focused on non-linear analysis based on concepts of chaos, fractality, and complexity: entropies, compression, fractal analysis, and wavelets. These methods have been successfully applied in the signal processing phase and increase knowledge about cardiovascular dynamics in healthy and pathological fetuses. This review summarizes those methods and investigates how non-linear measures are related to each paper's research objectives. Of the 388 articles obtained in the PubMed/Medline database and of the 421 articles in the Web of Science database, 270 articles were included in the review after all exclusion criteria were applied. While approximate entropy is the most used method in classification papers, in signal processing, the most used non-linear method was Daubechies wavelets. The top five primary research objectives covered by the selected papers were detection of signal processing, hypoxia, maturation or gestational age, intrauterine growth restriction, and fetal distress. This review shows that non-linear indices can be used to assess numerous prenatal conditions. However, they are not yet applied in clinical practice due to some critical concerns. Some studies show that the combination of several linear and non-linear indices would be ideal for improving the analysis of the fetus's well-being. Future studies should narrow the research question so a meta-analysis could be performed, probing the indices' performance.

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Heart Rate Variability, Emotions, and Music

Journal of Psychophysiology ◽

10.1027/0269-8803/a000021 ◽

2010 ◽

Vol 24 (2) ◽

pp. 112-119 ◽

Cited By ~ 9

Author(s):

F. Riganello ◽

A. Candelieri ◽

M. Quintieri ◽

G. Dolce

Keyword(s):

Data Mining ◽

Heart Rate ◽

Heart Rate Variability ◽

Vegetative State ◽

Low Frequency ◽

Emotional Reactions ◽

Heart Beat ◽

Healthy Controls ◽

Frequency Spectra ◽

Emotional Value

The purpose of the study was to identify significant changes in heart rate variability (an emerging descriptor of emotional conditions; HRV) concomitant to complex auditory stimuli with emotional value (music). In healthy controls, traumatic brain injured (TBI) patients, and subjects in the vegetative state (VS) the heart beat was continuously recorded while the subjects were passively listening to each of four music samples of different authorship. The heart rate (parametric and nonparametric) frequency spectra were computed and the spectra descriptors were processed by data-mining procedures. Data-mining sorted the nu_lf (normalized parameter unit of the spectrum low frequency range) as the significant descriptor by which the healthy controls, TBI patients, and VS subjects’ HRV responses to music could be clustered in classes matching those defined by the controls and TBI patients’ subjective reports. These findings promote the potential for HRV to reflect complex emotional stimuli and suggest that residual emotional reactions continue to occur in VS. HRV descriptors and data-mining appear applicable in brain function research in the absence of consciousness.

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Heart Rate Variability Analyses in Parkinson’s Disease: A Systematic Review and Meta-Analysis

Brain Sciences ◽

10.3390/brainsci11080959 ◽

2021 ◽

Vol 11 (8) ◽

pp. 959

Author(s):

Konstantin G. Heimrich ◽

Thomas Lehmann ◽

Peter Schlattmann ◽

Tino Prell

Keyword(s):

Parkinson’S Disease ◽

Heart Rate ◽

Parkinson's Disease ◽

Heart Rate Variability ◽

Meta Analysis ◽

Cardiac Activity ◽

Heart Rate Variability Analysis ◽

Short Term ◽

Variability Analysis ◽

Parasympathetic Regulation

Recent evidence suggests that the vagus nerve and autonomic dysfunction play an important role in the pathogenesis of Parkinson’s disease. Using heart rate variability analysis, the autonomic modulation of cardiac activity can be investigated. This meta-analysis aims to assess if analysis of heart rate variability may indicate decreased parasympathetic tone in patients with Parkinson’s disease. The MEDLINE, EMBASE and Cochrane Central databases were searched on 31 December 2020. Studies were included if they: (1) were published in English, (2) analyzed idiopathic Parkinson’s disease and healthy adult controls, and (3) reported at least one frequency- or time-domain heart rate variability analysis parameter, which represents parasympathetic regulation. We included 47 studies with 2772 subjects. Random-effects meta-analyses revealed significantly decreased effect sizes in Parkinson patients for the high-frequency spectral component (HFms2) and the short-term measurement of the root mean square of successive normal-to-normal interval differences (RMSSD). However, heterogeneity was high, and there was evidence for publication bias regarding HFms2. There is some evidence that a more advanced disease leads to an impaired parasympathetic regulation. In conclusion, short-term measurement of RMSSD is a reliable parameter to assess parasympathetically impaired cardiac modulation in Parkinson patients. The measurement should be performed with a predefined respiratory rate.

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The effect of level of injury and physical activity on heart rate variability following spinal cord injury

Journal of Spinal Cord Medicine ◽

10.1080/10790268.2017.1383709 ◽

2017 ◽

Vol 42 (2) ◽

pp. 212-219 ◽

Cited By ~ 2

Author(s):

Athanasios Kyriakides ◽

Dimitrios Poulikakos ◽

Angeliki Galata ◽

Dimitrios Konstantinou ◽

Elias Panagiotopoulos ◽

...

Keyword(s):

Physical Activity ◽

Spinal Cord ◽

Heart Rate ◽

Spinal Cord Injury ◽

Heart Rate Variability ◽

Cord Injury

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Effect of linear and non-linear measurements of heart rate variability in prediction of PAF attack

2017 25th Signal Processing and Communications Applications Conference (SIU) ◽

10.1109/siu.2017.7960358 ◽

2017 ◽

Cited By ~ 1

Author(s):

Ali Narin ◽

Mahmut Ozer ◽

Yalcin Isler

Keyword(s):

Heart Rate ◽

Heart Rate Variability ◽

Linear Measurements ◽

Non Linear

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Exercise intensity to maximal aerobic speed, physical activity level and heart rate variability in postmenopausal women

Cuadernos de Psicología del Deporte ◽

10.6018/cpd.379111 ◽

2020 ◽

Vol 20 (2) ◽

pp. 63-70

Author(s):

Felipe de Ornelas ◽

Danilo Rodrigues Batista ◽

Vlademir Meneghel ◽

Wellington Gonçalves Dias ◽

Guilherme Borsetti Businari ◽

...

Keyword(s):

Physical Activity ◽

Heart Rate ◽

Heart Rate Variability ◽

Physical Exercise ◽

Postmenopausal Women ◽

Aerobic Capacity ◽

Exercise Intensity ◽

Physical Activity Level ◽

Activity Level ◽

Maximal Aerobic Speed

Physical inactivity is main cause of disease worldwide. Identify the physical exercise preference, resulting in increases adherence and future intention to perform physical activity. The preference of the intensity of exercise questionnaire (PRETIE-Q) is the main tool used to assess preference in physical exercise. Variables as age, body mass index (BMI), usual physical activity level (PAL), maximal oxygen uptake (VO2máx), can influence in PRETIE-Q answers. The purpose of this study was investigate if there is relation between preference for exercise intensity with maximal aerobic speed (MAS), PAL and heart rate variability (HRV) in postmenopausal women phase. Participated of study 30 subjects who answer PRETIE-Q together with analyses of MAS, PAL and HRV. Preference was large correlated with MAS (r = 0.63), PAL (r = 0.57) and HRVRMSSD (r = 0.52). Together, MAS (40.4%), PAL (10.7%) and HRVRMSSD (6.4%) explained 57.5% of the preference score. This results study allow to health professional, that prescribe physical exercise, understand that subjects with high aerobic capacity, cardiovagal modulation and usual PAL will have preference for high intensity exercise. In consequence, can increase the adherence to systematic practice of physical exercise. Conclude that preference of exercise intensity for women in postmenopausal phase is related with aerobic capacity, high HRV and physical activity level.

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Autonomic and endothelial dysfunction with neurocirculatory asthenia in young men of call-up age

Pediatrician (St Petersburg) ◽

10.17816/ped10227-31 ◽

2019 ◽

Vol 10 (2) ◽

pp. 27-31

Author(s):

Vladimir S. Ivanov ◽

Lilia I. Levina ◽

Sergey N. Ivanov ◽

Vladimir S. Vasilenko

Keyword(s):

Heart Rate ◽

Heart Rate Variability ◽

Endothelial Dysfunction ◽

Cardiac Activity ◽

Young Men ◽

Mean Value ◽

Regulation Type ◽

Vasodilator Reserve ◽

Vegetative Regulation

Young men of call-up age with neurocirculatory were asthenia were examined for autonomic regulation of cardiac activity and vasodilatory reserve of the arteries. The functional state of the autonomic nervous system (ANS) was studied with the aid of rythmography with analyse of heart rate variability. The following parameters were studied: vegetative regulation type, responsiveness of departments of ANS and autonomic provision of cardiac activity. The type of vegetative regulation was determined by the mean value of RR interval and indication of the heart rate variability (∆RR). Reactivity of parasympathetic and sympathetic divisions of the ANS and autonomic support of cardiac activity were investigated using breathing test. To ensure vegetative dysadaptation cardiac activity includes reaction with low vegetative coverage of both divisions of the ANS and paradoxical reaction in which there is a decrease in ∆RRmax (instead of increase) and an increase in ∆RRmin instead of decrease. These reactions indicate autonomic dysfunction. Vasodilatory reserve of the arteries was investigated using ultrasonography of the brachial artery with compressive sample and determination of endothelium-dependent vasodilation. It was found that in boys with neurocirculatory asthenia vagotonic and sympathetic types of vegetative regulation are often determined by disadaptative vegetative provision of cardiac activity, which is accompanied by endothelial dysfunction with reduced vasodilator reserve of the arteries.

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