24h睡眠剥夺后作业效率与心率变异性的变化

目的:探索24h睡眠剥夺(Sleep Deprivation,SD)后作业效率和心率变异性的变化.方法:通过观察8名健康男性在24h睡眠剥夺前后的作业效率、主观脑力负荷和心率变异性的变化,寻找与脑力疲劳相关的敏感指标.结果:在24h睡眠剥夺后,NASA-TLX评分呈显著性增加(p＜0.05),75°立位时HF呈显著性减少(p＜0.05),TINN、LF/HF呈显著性增加(p＜0.05).结论:NAsA-TLX量表从主观感受上很好的反映了脑力疲劳后工作绩效下降的变化,HRV的变化主要原因在于24h SD后迷走神经活性降低,交感神经相对加强.     

Comparison of the Effects of Septoplasty and Sinus Lifting Simulation in Rats on Changes in Heart Rate Variability

Doklady Biochemistry and Biophysics - The effects of septoplasty and sinus lifting simulation in rats on changes in the frequency domain of heart rate variability were compared. In the early...     

The Relationship between p53-Positive Neurons and Dark Neurons in the Hippocampus of Rats after Surgical Interventions on the Nasal Septum

Doklady Biochemistry and Biophysics - The study evaluates the dependence of p53 protein expression on the appearance of dark neurons (DNs) in the hippocampus in rats during experimental modeling of...     

Seasonal Changes in Heart Rate Variability in 11- to 13-Year-Old Girls

Heart rate variability (HRV) was assessed each quarter during a year in 11- to 13-year-old girls with a Valenta medical diagnostic system. The HRV was highest in winter and lowest in summer (in 12-year-old girls) and autumn (in 11- and 13-year-old girls), indicating seasonal changes in the degree of β-adrenergic effects on the heart (lowest in winter and highest in summer and/or autumn). The changes were most pronounced in 11-year-old girls, i.e., at the onset of puberty. Seasonal changes in the HRV can be explained by changes in the blood levels of direct and indirect endogenous modulators of chemoresponsiveness and are considered to be a mechanism of human adaptation to external conditions.__________Translated from Fiziologiya Cheloveka, Vol. 31, No. 4, 2005, pp. 43–49.Original Russian Text Copyright © 2005 by Kaisina, Sizova, Tsirkin, Trukhina.     

Reduced Heart Rate Variability and Altered Cardiac Conduction after Pre-Eclampsia

Pre-eclampsia is a hypertensive disorder of pregnancy that is associated with elevated maternal risk for cardiovascular disease. The aims of this study were to determine the effect of normal pregnancy on postpartum parameters of the electrocardiogram, and furthermore to determine how a history of pre-eclampsia may affect these parameters. Ten-minute high-resolution (1000 Hz) orthogonal Holter electrocardiogram (ECG) recordings were used to measure heart rate variability (HRV). Signal-averaged P-wave and QRS complex durations were determined. Participants included non-pregnant controls, normotensive parous controls and women with a recent history of PE. While reductions in HRV induced by uncomplicated pregnancy returned to non-pregnant levels by 6–8 months postpartum HRV remained reduced in women with a history of PE compared to control groups. In addition, P-Wave and QRS complex durations were prolonged in PE subjects at 6–8 months postpartum compared to control groups. Only QRS duration was independent of differences in blood pressure. These results suggest increased sympathetic cardiac activity, and delayed myocardial conduction in women after PE; alterations consistent with cardiac remodeling and increased risk for arrhythmia. In examining the association between PE and cardiovascular disease, identification of ECG abnormalities soon after pregnancy in women with a history of PE highlights a unique opportunity for early identification and screening in this population before other risk factors become apparent.     

不稳定型心绞痛心率变异性特点及美托洛尔对其的影响

目的:了解心率变异性(heart rate variability,HRV)在不稳定型心绞痛(unstable angina pectoris,UAP)发病中的作用及其用于病情严重程度判断的价值;了解美托洛尔对UAP患者HRV的影响。方法:选择年龄、性别相匹配的UAP患者、SAP患者和健康人各60例做动态心电图检查,经Holter软件分析进行HRV时域指标的比较。UAP组动态心电图检查后加用美托洛尔25-50 mg/d(分两次口服),20天后重复动态心电图检查。结果:1UAP组与正常组比较各项指标均降低(P0.01)。2正常人HRV具有昼夜节律变化的特点,UAP组HRV昼夜节律变化性降低。3UAP病人服用美托洛尔后,心肌缺血、心律失常得到改善。结论:1.UAP患者心脏自主神经活性主要是副交感神经活性受损,交感神经活性相对占优势。2.无合并症的UAP病人HRV呈昼夜节律性降低。3.美托洛尔可改善UAP患者HRV。     

The Effects of Helium-Generated Cold Plasma on the Parameters of Heart Rate Variability in Rats

Biophysics - Abstract—The goal of the present study was to evaluate the mechanism of the systemic response to helium-generated cold plasma based on heart rate variability indices in rats. The...     

Diurnal Variation in Heart Rate Variability before and after Maximal Exercise Testing

As heart-rate variability (HRV) is under evaluation in clinical applications, the authors sought to better define the interdependent impact of age, maximal exercise, and diurnal variation under physiologic conditions. The authors evaluated the diurnal changes in HRV 24-h pre- and post-maximal aerobic exercise testing to exhaustion in young (19–25 yrs, n?=?12) and middle-aged (40–55 yrs, n?=?12) adults. Subjects wore a portable 5-lead electrocardiogram holter for 48?h (24?h prior to and following a maximal aerobic capacity test). Time-, frequency-, time-frequency-, and scale-invariant-domain measures of HRV were computed from RR-interval data analyzed using a 5-min window size and a 2.5-min step size, resulting in a different set of outputs every 2.5?min. Results were averaged (mean?±?SE) over four prespecified time periods during the morning, afternoon, evening, and night on Day 1 and Day 2. Diurnal changes in HRV in young and middle-aged adults were compared using a two-way, repeated-measures analysis of variance (ANOVA). Young adults demonstrated higher HRV compared to middle-aged adults during periods of wakefulness and sleep prior to maximal exercise stress testing (i.e., high-frequency power during Day 1: young adults: morning 1862?±?496?ms², afternoon 1797?±?384?ms², evening 1908?±?431?ms², and night 3202?±?728?ms²; middle-aged adults: morning 341?±?53?ms², afternoon 405?±?68?ms², evening 469?±?80?ms², and night 836?±?136?ms²) (p < .05). Exercise resulted in reductions in HRV such that multiple measures of HRV were not significantly different between age groups during the afternoon and evening periods. All measures of HRV demonstrated between-group differences overnight on Day 2 (p < .05). Young adults are associated with higher baseline HRV during the daytime. Sleep increases variability equally and proportionally to daytime variability. Given the higher baseline awake HRV and equal rise in HRV during sleep, the change in HRV from sleep to morning with exercise is greater in younger subjects. These physiologic results have clinical significance in understanding the pathophysiology of altered variability in ill patients. (Author correspondence: aseely@ohri.ca)     

Heart Rate Variability in Healthy Six- to Sixteen-Year-Old Children

To study the age-related features of heart rate variability in children between the age of 6 to 16 years, cardiac rhythmograms of 5400 children were analyzed. It was found that parameters of the heart rate (M, SDNN, RMSSD, TF, VLF, and HF) in these children increase with age, changing in a wavelike way from year to year. Gender differences were observed in parameter M beginning from the age of 9; in parameters TF, VLF, and LF, the differences were observed beginning from the age of 11; and in parameters SDNN, RMSSD, and HF, the differences were observed from the age of 12 years. No differences between 16-year-old boys and girls in all the parameters of heart rate variability were found. It was shown that parameter VLF derived from ECG epochs of less than 5-min is suitable for physiological and clinical assessment. The obtained values of the parameters can be used in practice as reference standard.     

Heart Rate and Heart Rate Variability in Dairy Cows with Different Temperament and Behavioural Reactivity to Humans

From the 1990s, extensive research was started on the physiological aspects of individual traits in animals. Previous research has established two extreme (proactive and reactive) coping styles in several animal species, but the means of reactivity with the autonomic nervous system (ANS) activity has not yet been investigated in cattle. The aim of this study was the characterization of cardiac autonomic activity under different conditions in cows with different individual characteristics. For this purpose, we investigated heart rate and ANS-related heart rate variability (HRV) parameters of dairy cows (N = 282) on smaller- and larger-scale farms grouped by (1) temperament and (2) behavioural reactivity to humans (BRH). Animals with high BRH scores were defined as impulsive, while animals with low BRH scores were defined as reserved. Cardiac parameters were calculated for undisturbed lying (baseline) and for milking bouts, the latter with the presence of an unfamiliar person (stressful situation). Sympathetic tone was higher, while vagal activity was lower in temperamental cows than in calm animals during rest both on smaller- and larger-scale farms. During milking, HRV parameters were indicative of a higher sympathetic and a lower vagal activity of temperamental cows as compared to calm ones in farms of both sizes. Basal heart rate did not differ between BRH groups either on smaller- or larger-scale farms. Differences between basal ANS activity of impulsive and reserved cows reflected a higher resting vagal and lower sympathetic activity of reserved animals compared to impulsive ones both on smaller- and larger-scale farms. There was no difference either in heart rate or in HRV parameters between groups during milking neither in smaller- nor in larger-scale farms. These two groupings allowed to draw possible parallels between personality and cardiac autonomic activity during both rest and milking in dairy cows. Heart rate and HRV seem to be useful for characterisation of physiological differences related to temperament and BRH.     

Heart Rate Variability and Autonomic Modulations in Preeclampsia

BackgroundAlthough the exact pathophysiology of preeclampsia is not well understood, autonomic nervous system imbalance is suggested as one of the main factors.AimsTo investigate heart rate variability (HRV) and autonomic modulations in Sudanese pregnant women with preeclampsia.ResultsPatients with preeclampsia achieved significantly higher LF Norm [49.80 (16.25) vs. 44.55 (19.15), P = 0.044] and LnLF/HF [0.04 (0.68) vs. -0.28 (0.91), P = 0.023] readings, but lower HF Norm [49.08 (15.29) vs. 55.87 (19.56), P = 0.012], compared with healthy pregnant women. Although all other HRV measurements were higher in the patients with preeclampsia compared with the controls, only LnVLF [4.50 (1.19) vs. 4.01 (1.06), P = 0.017] and LnLF [4.01 (1.58) vs. 3.49 (1.23), P = 0.040] reached statistical significance.ConclusionThe study adds further evidence for the dominant cardiac sympathetic modulations on patients with preeclampsia, probably secondary to parasympathetic withdrawal in this group. However, the higher LnVLF and LnLF readings achieved by preeclamptic women compared with the controls are unexpected in the view that augmented sympathetic modulations usually depresses all HRV parameters including these two measures.     

Heart Rate Variability in 12- to 13-Year-Old Adolescents

Neurophysiology - Estimation of age and gender peculiarities of heart rate variability (HRV) in adolescents will help researchers to predict the potential abilities of the adaptation mechanisms, to...     

An Examination of the Relationship Between Resting Heart Rate Variability and Heart Rate Reactivity to a Mental Arithmetic Stressor

Resting heart rate variability can be an index of sympathetic or parasympathetic dominance, according to the frequency of the variability studied. Sympathetic dominance of this system has been linked to increased risk of cardiovascular disease (CVD). Similarly, rapid and dramatic increases in heart rate reactivity to a stressor task have also been suggested as indicating increased risk of CVD via atherogenesis. Although both of these variables have been related to the development of cardiovascular disease, and both may be related to increased sympathetic activity or parasympathetic withdrawal, most research studies have tended to focus on either variable independently of the other. In order to investigate whether these two indices of stressor reactivity were related in relatively young and healthy subjects, resting heart rate variability data were collected from 80 volunteers for 20 minutes. In addition, heart rate reactivity data were collected during a 2-minute mental arithmetic stressor, which has been previously shown to induce significant increases in heart rate. After classifying subjects according to whether their heart rate variability data were above or below the mean for their gender, heart rate reactivity data were examined via MANOVA to detect significant differences between subject groups. Females showed significant effects, and males showed nonsignificant trends, but these two sets of data were in different directions, suggesting that gender may be a confounding factor in the relationship between heart rate reactivity and heart rate variability.     

鼻中隔成形术中鼻腔填塞法及鼻中隔“8”字缝合法的疗效比较研究

目的:探讨鼻中隔成形术中鼻腔填塞法及鼻中隔"8"字缝合法的疗效。方法:选取2017年7月~2018年7月期间我院收治的拟行鼻中隔成形术的鼻中隔偏曲患者60例。采用乱数表法将患者分为对照组、实验组两组,各30例患者,两组患者均行鼻内镜下鼻中隔成形术,术后对照组给予鼻腔填塞法处理,实验组给予鼻中隔"8"字缝合法处理。比较两组术后临床疗效、鼻粘膜水肿情况,观察两组不同时间点视觉疼痛模拟评分(VAS)情况,记录两组患者术后鼻中隔并发症发生情况。结果:实验组术后7d临床总有效率为96.67%(29/30),显著高于对照组患者的80.00%(24/30),差异有统计学意义(P0.05)。与术前相比,两组患者术后12hVAS评分升高,术后24h、术后48hVAS评分下降(P0.05);与术后12h相比,两组患者术后24h、术后48hVAS评分均下降,且术后48hVAS评分低于术后24h(P0.05);实验组术后12h、术后24h、术后48hVAS评分均低于对照组(P0.05)。实验组鼻粘膜水肿0级患者数量显著高于对照组,鼻粘膜水肿1级患者数量显著低于对照组(P0.05);两组鼻粘膜水肿2级患者数量比较差异无统计学意义(P0.05);两组患者鼻中隔并发症总发生率比较差异无统计学意义(P0.05)。结论:相较于鼻腔填塞法,鼻中隔成形术中采用鼻中隔"8"字缝合法疗效显著,可减轻患者疼痛,改善患者鼻粘膜水肿情况,且不会增加并发症发生率,具有一定的临床应用价值。     

Analysis of Heart Rate Variability in Space Medicine

Space medicine was one of the first fields of science and practice to use the analysis of the heart rate variability (HRV) for obtaining new scientific information and solving the tasks of exercising medical control over humans working under extreme conditions. The theoretical basis of HRV analysis and different approaches to the assessment of the data obtained are presented in the work. The technique for HRV analysis with regard to the specifics of space studies is described. The results of investigations at different stages of the space flight, including the use of Holter monitoring, are presented. Special attention is given to the results of the investigations in a long-term 14-month space flight. The adaptation to long-term weightlessness was shown to be of a multistep character with the gradual involvement of additional regulatory mechanisms.     

Analysis of Heart Rate Variability in Masked Hypertension

To investigate heart rate variability (HRV) in patients with masked hypertension (MH), participants were classified based on clinic and 24-h ambulatory blood-pressure monitoring: essential hypertension (EH, n = 40; MH, n = 36) and normotension (NT, n = 48). The HRV parameters were observed using a 24-h Holter monitor. Compared with NT controls, the parameters of HRV (SDNN, SDANN, SDNN Index, RMSSD, HF) and parameters in EH and MH patients had significantly decreased. No statistically significant difference in the HRV parameters was found between the EH and MH groups. The changes in HRV parameters show cardiac autonomic nerve dysfunction in patients with MH.     

Heart Rate in Rats Exposed to Constant Magnetic Fields

The heart rate in rats exposed to a constant magnetic field 30 min a day for 14 successive days was examined. The animals were fixed between the poles of an electromagnet producing a DC field vertically oriented in the region of the animal's head and spine. The electrocardiogram of each animal was taken during the exposure and during the next 60 min. The heart rate was calculated every 3 min. It was found that a DC magnetic field of relatively high intensity (0.7 T) significantly increased the heart beat in the experimental animals compared to controls.     

Deceleration Trauma to the Heart and Great Vessels after Road-traffic Accidents

Four young men involved in high-speed car crashes developed cardiovascular trauma. Two patients had aortic aneurysms, one rupture of the mitral valve, and one ventricular septal defect; successful surgical correction was undertaken in all. The importance of considering the possibility of cardiovascular trauma in these circumstances is emphasized, and x-ray films (repeated if necessary) should be taken even when there are no external signs of trauma.     

Analysis of Heart Rate Variability Based on the Graph Method

A method of analysis of heart rate variability based on the graph theory principle was suggested. The main parameters of the heart rate graph structure were determined and analyzed using models of harmonic oscillations, white noise, and various functional tests (including controllable respiration and mental load). The efficiency of the use of parameters of the heart rate graph for diagnosing some functional states was considered. A correlation of the parameters of the heart rate graph structure with the frequency characteristics of heart rate variability was studied. A general model of changes in the heart rate graph structure parameters at different levels of mental activity was constructed in terms of entropy changes.