scholarly journals Effect of High-Induction Magnetic Stimulation on Complex Heart Rate Variability of Sus Scrofa Domesticus under General Anesthesia

2020 ◽  
Vol 10 (2) ◽  
pp. 589 ◽  
Author(s):  
Lenka Hanáková ◽  
Jaroslav Průcha ◽  
Vladimír Socha ◽  
Milan Štengl ◽  
Sarah Van den Bergh

Modern approaches to physical therapy often use electric currents induced by time-varying magnetic fields. Although some of these methods are already commonly used, and only a few studies are looking at applying particular techniques on exposed tissue. In this study, a high-induction magnetic stimulation (HIMS) was applied to the chest area to affect the electrical conduction system of the heart. The animal model Sus scrofa domesticus was used for the study. Standard methods were used to make the subsequent analysis, i.e., heart rate variability in time and frequency domain. Concerning the nonlinear character of the electrocardiographic signal and evaluating complex variability (complexity), recurrent quantification analysis was used. The results show high resistance to a physiologically working heart, but there are also specific changes concerning complex variability. Thus, the results indicate that the HIMS application in the chest area may not pose a significant risk to healthy individuals in terms of the short-term effect of this technique on cardiac activity. However, cardiac activity is still, to some extent, affected by the HIMS application. In view of this and the fact that the study was conducted on an animal model, further research in this area would be appropriate.

Animals ◽  
2021 ◽  
Vol 11 (7) ◽  
pp. 2019
Author(s):  
Salvatore Desantis ◽  
Serena Minervini ◽  
Lorenzo Zallocco ◽  
Bruno Cozzi ◽  
Andrea Pirone

The pig has been increasingly used as a suitable animal model in translational neuroscience. However, several features of the fast-growing, immediately motor-competent cerebral cortex of this species have been adequately described. This study analyzes the cytoarchitecture of the primary motor cortex (M1) of newborn, young and adult pigs (Sus scrofa domesticus). Moreover, we investigated the distribution of the neural cells expressing the calcium-binding proteins (CaBPs) (calretinin, CR; parvalbumin, PV) throughout M1. The primary motor cortex of newborn piglets was characterized by a dense neuronal arrangement that made the discrimination of the cell layers difficult, except for layer one. The absence of a clearly recognizable layer four, typical of the agranular cortex, was noted in young and adult pigs. The morphometric and immunohistochemical analyses revealed age-associated changes characterized by (1) thickness increase and neuronal density (number of cells/mm2 of M1) reduction during the first year of life; (2) morphological changes of CR-immunoreactive neurons in the first months of life; (3) higher density of CR- and PV-immunopositive neurons in newborns when compared to young and adult pigs. Since most of the present findings match with those of the human M1, this study strengthens the growing evidence that the brain of the pig can be used as a potentially valuable translational animal model during growth and development.


2021 ◽  
Vol 11 (8) ◽  
pp. 959
Author(s):  
Konstantin G. Heimrich ◽  
Thomas Lehmann ◽  
Peter Schlattmann ◽  
Tino Prell

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.


2019 ◽  
Vol 10 (2) ◽  
pp. 27-31
Author(s):  
Vladimir S. Ivanov ◽  
Lilia I. Levina ◽  
Sergey N. Ivanov ◽  
Vladimir S. Vasilenko

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.


2021 ◽  
Vol 8 ◽  
Author(s):  
Kaho Kitajima ◽  
Kazato Oishi ◽  
Masafumi Miwa ◽  
Hiroki Anzai ◽  
Akira Setoguchi ◽  
...  

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.


2021 ◽  
Author(s):  
Daniel Escutia-Reyes ◽  
José Garduño-García ◽  
Gerardo López-Chávez ◽  
Ángel Gómez-Villanueva ◽  
Adriana Pliego-Carrillo ◽  
...  

Abstract Purpose: To explore cardiac autonomic changes assessed by linear and nonlinear indexes of heart rate variability (HRV) and body composition modifications in breast cancer survivors and cancer-free control women. Methods: Women who were breast cancer survivors (BCS, n=27) and cancer-free control participants with similar characteristics (Control, n=31) were enrolled in the Regional General Hospital No. 251 of the Mexican Institute of Social Security (Metepec, Mexico). We processed five minutes of R-R interval time series, and we calculated relevant linear and nonlinear parameters of HRV such as mean RR interval (RRave), the Root Mean Square of the Successive Differences (RMSSD), the Poincaré plot measures SD1, SD2, SD1/SD2, and the sample entropy (SampEn). Additionally, we indirectly assessed body composition measures such as body weight, fat mass, visceral fat rating (VFR), normalized VRF (nVFR), muscle mass, metabolic age, and total body water.Results: We found that diverse HRV indexes and only one body composition measure showed statistical differences (p<0.05) between the BCS and Control groups: RRave: 729 (648–802) vs. 795 (713–852) ms; RMSSD: 16.5 (8.9–27.0) vs. 19.7 (14.2–28.5) ms; SD1: 11.6 (6.3–19.0) vs. 13.9 (10.0–20.1) ms; SD1/SD2: 2.5 (2.1–3.3) vs. 2.2 (1.9–2.7), SampEn: 1.5 (1.3–1.8) vs. 1.7 (1.5–1.8), and nVFR 0.12 (0.11–0.13) vs.0.10 (0.08–0.12) points/kg, respectively. The nVFR was significantly correlated to several indexes of HRV.Conclusions: BCS exhibit a lower parasympathetic cardiac activity and changes in HRV patterns than controls, likely because of the concomitant increase of visceral fat.


2020 ◽  
Author(s):  
Baolin He ◽  
Wenyu Li ◽  
Xiaotong Zhang ◽  
Yanan Wu ◽  
Jing Liu ◽  
...  

Abstract Background: Frequent cessations of respiration can greatly increase the prevalence rate of arrhythmia. It has been confirmed that cardiac activity is regulated by autonomic nervous system (ANS). And heart rate variability (HRV) is widely used as a method to evaluate the function of ANS. Therefore, we analyzed whether apnea can affect the balance and normal function of ANS using short-term HRV indices. Methods: Forty-five healthy subjects were asked to breathe normally and hold their breathing to simulate 10 times apnea. Thirty-six patients from the dataset of a sleep laboratory for the diagnosis of sleep disorders with 10 times apnea were included in analysis. We calculated short-term HRV indices of subjects in normal respiratory and apneic states, respectively. Results: Compared with normal respiratory state, respiration cease would lead to the values of the mean-RR, nLF, LF/HF, and α1 were significantly increase whereas the values of rMSSD and nHF were significantly decrease. Conclusions: Cessations of respiration would lead to an imbalance in function of ANS, as well as an increase in fractal characteristics of the heart. These changes in physiological state are likely to induce and cause the occurrence of arrhythmia, which is regulated by ANS.


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