优秀散打运动员的心率变异性

目的:分析散打运动对心率变异性影响的规律。方法:于2004-09/2004-12随机选取山东省武术院一线优秀散打男运动员和山东师范大学体育学院学生为受试对象。采用MCA-3C心脏(功能)信息综合检测仪,分别对优秀散打运动员27人、山东师范大学体育学院民体系学生52人、体育系学生60人、普通系学生70人的心率变异性进行时域和频域分析。时域分析采用的指标有:平均心率、平均R-R间期值、最大的R-R间期值、最小的R-R间期值、R-R间期的标准差、连续两次R-R间期之差的标准差、R-R间期与平均R-R间期值之差大于50ms的个数占总数的百分比(P50)。频域分析采用的指标有:全频范围内的总功率(ms2)、低频段频峰的位置(Hz)、低频段频峰的功率谱密度(ms2/Hz)、低频段的功率(ms2)、高频段频峰的位置(Hz)、高频段频峰的功率谱密度(ms2/Hz)、高频段的功率(ms2)、低频段和中频段的功率与高频段功率的比值。结果:受试209人均完成测试,全部进入结果分析。①体育系和民体系学生的平均心率显著低于普通系学生(P<0.05);但平均R-R间期值、最大的R-R间期值、最小的R-R间期值、R-R间期的标准差、连续两次R-R间期之差的标准差、R-R间期与平均值之差大于50ms的个数占总数的百分比、全频范围内的总功率均显著高于普通系学生(P<0.05)。②优秀散打运动员的平均心率、低频和中频段的功率与高频段功率的比值显著低于普通系学生(P<0.05);而平均R-R间期值、最大的R-R间期值、最小的R-R间期值、连续两次R-R间期之差的标准差、高频段频峰的位置均显著高于普通系学生(P<0.05);且优秀散打运动员的高频段频峰的位置也显著高于体育系及民体系学生(P<0.05)。结论:运动训练可明显提高安静时心率变异性,提高心迷走神经张力,减低心脏性猝死的可能性。优秀散打运动员具有更高的心率变异性,具有更高的迷走神经张力和更低的交感神经张力,拥有较高的自主神经调节能力储备,是其训练水平高和机能状态好的重要表现之一。提示心率变异性指标可用作散打运动员选材、训练效果评定及机能水平评价的有效指标之一。     

高血压病心率变异性分析

目的　探讨高血压病及其不同发病阶段心率变异性的改变。方法　原发性高血压病人６８ 例,按心功能分级,对照组３８ 例,记录２４ 小时动态心电图,进行心率变异性的时域分析和频域分析。结果　（１） 高血压病组功率谱的低频（ＬＦ）成分明显低于正常对照组（ Ｐ＝ ０ ．００２） ;（２） 高血压病不同阶段ＬＦ 存在极显著差异（ Ｐ＜ ０ ．００１） ,心功能越差,ＬＦ 减低愈明显;ＳＤＡＮＮ 在心功能越差者降低明显（ Ｐ＝ ０ ．０２） 。结论　高血压病患者自主神经功能改变,且心功能越差时,变化愈显著。     

心率变异性临床分析396例

我院自1994年11月至1995年4月共做心率变异性（HRV）分析396例，结果表明，HRV与冠心病、高血压病等其它心脏病及一些非心血管疾患有明显的相关性，这与文献报道是一致的，其中：冠心病、高血压病时HRV下降显著。提示迷走神经受损程度最为严重（x2≥18.35，P＜0．01），糖尿病等非心血管疾患HRV下降次之，（x2=16．83、P＜0．01），而病毒性心肌炎时，HRV下降甚轻，提示：迷走神经受损程度最小。（x2＝6．62、P＜0.05）.     

心率变异性研究进展

大量流行病学资料显示,心率变异性的降低在一般人群及心血管疾病人群中都预示着不良预后,包括高血压、充血性心力衰竭、心肌梗死后致死性心律失常、糖尿病神经症等,并且低心率变异性已被证实为心律失常事件和心肌梗死后死亡的独立危险因子。近年来,心率变异性的分析方法不断改进,并出现一些新的方式,这对于相关疾病预后的评估具有重要意义。     

心率变异性的临床应用研究

1978年Ｗｏｌｆ等首先发现急性心肌梗死 (ＡＭＩ)后心律变异性 (ＨＲＶ)降低与严重心律失常和病死率密切关系。自此 ,对ＨＲＶ生理和病理学意义进行了较为广泛和深入的研究。业已证实 ,ＨＲＶ是判断自主神经活动的最好方法[1] 。ＨＲＶ分析在ＡＭＩ和糖尿病中的应用价值已得到肯定 ,在多种心血管和非心血管疾病研究中展示广泛的应用前景 ,已成为无创心电检测技术的研究热点之一[2 ] 。1　预测心脏猝死心肌细胞的电稳定性依赖于交感神经、迷走神经和体液调节之间的平衡。交感神经兴奋可降低室颤阈 ,迷走神经兴奋可提高室颤阈。一旦植物神经对…     

肥厚型心肌病的心率变异性改变

本研究对用心率变异性 (ＨＲＶ)时域和频域方法分析肥厚型心肌病的自主神经功能变化和相关因素做相关分析。1　材料与方法1 1　病例选择　选择我院 1993～ 1995年门诊及住院肥厚型心肌病 2 2例患者 ,年龄 2 8～ 5 2 (平均 38± 8)岁 ,男 13例 ,女 9例 ,另选性别年龄与之相符的 2 2例健康人为对照组。1 2　ＨＲＶ测定　采用长程法 ,用美国Ｂｉｏｍｅｄｉｃａｌ.ｓｙｓｔｅｍ公司的新世纪智能动态心电图监测系统 ,选择ＣＭ1、ＣＭ5及相似ａＶＦ式Ⅲ导三个导联 ,对磁带记录到的心电信号经Ａ/Ｄ转换器转换成数字信号输入微机 ,经ＨＲＶ分析软件 …     

健康成人的心率变异性分析

目的：探讨健康成人心率变异（ＨＲＶ）的长程时域及频域分析的参考正常范围，方法：记录２３０例健康成人的２４小时动态心电图，电脑自动分析ＨＲＶ各参数。结果：（１）２４小时的ＨＲＶ时域参数的正常值与文献报道相近，频域参数均低于短程的正常值；（２ＨＲＶ各参数均随年龄增长而变小，女性ＨＲＶ参数多低于男性；（３）ＨＲＶ各指标间有高度相关性。结论：对长程ＨＲＶ的分析，时域方法和频域方法同样适用，国餐提出的ＨＲＶ     

尿毒症患者的心率变异性及其意义

心率变异性(HRV)是指逐次心跳间期之间的微小变异,可作为反映自主神经系统对心血管活动控制的指标。本文分析了20例尿毒症维持血透患者的24小时动态心电图资料,并与36例正常人作对照,对其HRV变化及临床意义进行探讨。     

Heart rate variability in free diving athletes

The aim of the study was to evaluate the cardiac autonomic activity in free diving (FD) athletes. Thirteen Greek male free divers (group I, aged 33.4 ± 6.3 years, 6.6 ± 4.5 years of training experience) volunteered to participate while 13 age-matched sedentary subjects served as control group (group II). All subjects were submitted to ambulatory 24-h ECG recording for heart rate variability (HRV) analysis on a day of regular activities with no exercise or training. The results showed that group I had significantly lower minimum and mean heart rate by 23.9% (P < 0.001) and 20.6% (P < 0.001), respectively. All the measured time and frequency domain indices of HRV which reflect cardiac parasympathetic activity were higher in group I than in group II by 37.6% to 146% (P < 0.001). Conclusively, the resting cardiac autonomic activity and especially the parasympathetic branch was significantly increased in free divers compared to untrained subjects. This finding should be rather attributed to the accumulated effect of both exercise training and frequent exposure to FD stimulus.     

Heart rate variability stabilization in athletes: towards more convenient data acquisition

Resting heart rate variability (HRV) is a potentially useful marker to consider for monitoring training status in athletes. However, traditional HRV data collection methodology requires a 5‐min recording period preceded by a 5‐min stabilization period. This lengthy process may limit HRV monitoring in the field due to time constraints and high compliance demands of athletes. Investigation into more practical methodology for HRV data acquisitions is required. The aim of this study was to determine the time course for stabilization of ECG‐derived lnRMSSD from traditional HRV recordings. Ten‐minute supine ECG measures were obtained in ten male and ten female collegiate cross‐country athletes. The first 5 min for each ECG was separately analysed in successive 1‐min intervals as follows: minutes 0–1 (lnRMSSD_0–1), 1–2 (lnRMSSD_1–2), 2–3 (lnRMSSD_2–3), 3–4 (lnRMSSD_3–4) and 4–5 (lnRMSSD_4–5). Each 1‐min lnRMSSD segment was then sequentially compared to lnRMSSD of the 5‐ to 10‐min ECG segment, which was considered the criterion (lnRMSSD_Criterion). There were no significant differences between each 1‐min lnRMSSD segment and lnRMSSD_Criterion, and the effect sizes were considered trivial (ES ranged from 0·07 to 0·12). In addition, the ICC for each 1‐min segment compared to the criterion was near perfect (ICC values ranged from 0·92 to 0·97). The limits of agreement between the prerecording values and lnRMSSD_Criterion ranged from ±0·28 to ±0·45 ms. These results lend support to shorter, more convenient ECG recording procedures for lnRMSSD assessment in athletes by reducing the prerecording stabilization period to 1 min.     

Heart rate variability]

Heart rate variability (HRV) has become a useful parameter for the quantification of autonomic nervous function. HRV has been quantified, either by time domain or frequency domain analysis. Time domain measures, such as CVRR and RR50, are easy to calculate but they only provide information related to parasympathetic activity. The spectral analyses, on the other hand, give us information concerning 3 oscillatory components. The high frequency band (the frequency between 0.15-0.5 Hz) is known as the respiratory sinus arrhythmia (RSA), and the middle frequency band (0.88-0.15 Hz) is attributed to baroreflex components. The low frequency band (0.01-0.08 Hz) may be of various origins, such as blood flow rhythm, periodic respiration (including Cheyne-Stokes respiration), renin-angiotensin, and thermal regulation. The efferent nerve to the high frequency band is totally operated by the parasympathetic system. The low frequency band is regulated by both sympathetic and parasympathetic nervous systems. We demonstrated that the diurnal variation of HRV may afford additional information, such as ultradian changes of autonomic activity, possibly due to REM/NREM cycles. It is believed that simultaneous monitoring of other physiological parameters such as EEG, EOG, respiration, and blood pressures, might give us information concerning the dynamic nature of autonomic nervous function.     

Heart rate variability in diabetes patients

Diabetes mellitus can cause cardiovascular autonomic neuropathy and is associated with increased cardiovascular deaths. We investigated cardiovascular autonomic neuropathy in diabetics and healthy controls by analysis of heart rate variability. Thirty-one diabetics and 30 age- and sex-matched controls were included. In the time domain we measured the mean R - R interval (NN), the standard deviation of the R - R interval index (SDNN), the standard deviation of the 5-min R - R interval mean (SDANN), the root mean square of successive R - R interval differences (RMSSD) and the percentage of beats with a consecutive R - R interval difference > 50 ms (pNN50). In the frequency domain we measured high-frequency power (HF), low-frequency power (LF) and the LF/HF ratio. Diabetes patients had lower values for time-domain and frequency-domain parameters than controls. Most heart rate variability parameters were lower in diabetes patients with chronic complications than in those without chronic complications.     

Heart rate variability reproducibility during exercise

The use of heart rate variability (HRV) parameters during exercise is not supported by appropriate reliability studies. In 80 healthy adults, ECG was recorded during three 6 min bouts of exercise, separated by 6 min of unloaded cycling. Two bouts were at a moderate intensity while the final bout was at a heavy exercise intensity. This protocol was repeated under the same conditions on three occasions, with a controlled start time (pre-determined at the first visit). Standard time and frequency domain indices of HRV were derived. Reliability was assessed by Bland–Altman plots, 95% limits of agreement and intraclass correlation coefficients (ICC). The sample size required to detect a mean difference ≥30% of the between-subject standard deviation was also estimated. There was no systematic change between days. All HRV parameters demonstrated a high degree of reproducibility during baseline (ICC range: 0.58–0.75), moderate (ICC: 0.58–0.85) and heavy intensity exercise (ICC range: 0.40–0.76). The reproducibility was slightly diminished during heavy intensity exercise relative to both unloaded baseline cycling and moderate exercise. This study indicates that HRV parameters can be reliably determined during exercise, and it underlines the importance of standardizing exercise intensity with regard to fitness levels if HRV is to be reliably determined.     

Heart rate variability and 24-hour minimum heart rate

Heart rate variability (HRV) indices based on 24-hr electrocardiograph recordings have been used in clinical research studies to assess the aggregate activity of the autonomic nervous system. Although 24-hr HRV is generally considered noninvasive, use in research protocols typically involves considerable data collection and processing expenses and substantial participant burden. The purposes of this research methods evaluation were to describe the relationships between 24-hr minimum heart rate (HR) and several 24-hr time domain HRV indices (Ln SDNN, Ln SDANN, Ln SDNNIDX, Ln RMSSD, and Logit50) across several research data sets (normal women, normal men, children enrolled in a study of recurrent abdominal pain, women with irritable bowel syndrome, sudden cardiac arrest survivors, and heart failure patients) and to explore the possibility that 24-hr minimum HR might serve as a simpler alternative or adjunct to HRV measures in some situations. The correlations of global HRV measures (e.g., Ln SDNN, Ln SDANN) with 24-hr minimum HR were consistently larger (typical r approximately -.80) than with average HR (typical r approximately -.50). In repeated measurements, change in minimum HR was also correlated with change in general HRV (typical r approximately -.60). However, modest differentiation of minimum HR and HRV measures was noted in patients taking certain classes of cardiac medications (e.g., anti-arrhythmics, beta blockers). Twenty-four-hour minimum HR is correlated with general time domain HRV measures and might be useful as a simpler proxy, surrogate, or auxiliary variable in some clinical research applications, especially those in which participants are not receiving cardiac medications.