心率变异性的临床意义

正常情况下,心脏节律会随机体状况和昼夜时间而改变,这种心率的规则性变化称心率变异性（HRV）。通过测量连续的正常R—R间距变化的系数,从而反映心率的变化程度。正常人的心率为窦性心律,窦房结是心脏的主导起搏点．而窦房结细胞的活动受交感神经及迷走神经的双重支配。交感神经兴奋时加快窦房结细胞的自发性舒张期除极,使蜜房结冲动形成,因而心率增快;而迷走神经兴奋时心率减慢。心率的综合反应取决于交感神经与迷走神经的动态平衡,心率的即刻变化由迷走神经控制．交感神经仅起辅助作用。交感、迷走神经问的相互协调作用维持着正常人的心脏节律及心脏的正常活动．所以迷走神经功能兴奋时HRV大;迷走神经功能受损时HRV小。     

老年患者胃镜检查时心脏自主神经功能的变化

目的 观查和分析老年患者胃镜检查时心脏自主神经功能的变化及意义.方法 按序选取30例胃镜检查患者,年龄60～84岁;采用心率血压监测仪定患者胃镜检查前及检查时心率变异性(HRV)[包括平均R-R间期(RRI)、总变异性(Tv)、低频成份(LF)、高频成份(HF)低频成份/高频成份[LF/HF]和压力反射敏感性(BRS)[包括血压总变异(BRSTV)、血压谱密度的低频成份(BRSLF)、血压谱密度的高频成份(BRSHF)、血压谱密度的甚低频成份(BRSVLF)]的变化,分析检查前及检查时患者自主神经功能的变化.结果 检查时HRV指标RRI、TV、LF、HF和BRS指标BRS TV、BRS LF、BRS HF、BRS VLF均较检查前有明显升高(P=0.00),检查时LF/HF也较检查前升高(P=0.042.结论 老年患者者胃镜检查时交感神经和迷走神经兴奋性均增强,交感神经兴奋性增强可能更明显.     

替米沙坦对原发性高血压病合并2型糖尿病患者的心率变异性的影响

目的探讨原发性高血压病合并2型糖尿病患者的心率变异性（HRV）特点及替米沙坦对其的影响。方法50例原发性高血压病合并2型糖尿病患者，口服替米沙坦（80mg／d）8周前后HRV变化并与正常对照组（40例）比较。结果原发性高血压病合并2型糖尿病患者的HRV治疗前明显低于正常人，予替米沙坦8周干预治疗后HRV值明显上升。低频功率与高频功率比值（LF／HF）显著降低（P〈0．01）。结论原发性高血压病合并2型糖尿病患者自主神经活动明显受损，其迷走神经张力降低，交感神经张力相对增高，发生心源性猝死的危险性明显增加。替米沙坦能有效地提高心脏迷走神经张力，降低交感神经张力，有可能减少心律失常性死亡。     

心血管神经机能症的短时心率变异研究

应用短时心率变异（HRV）分析研究108例心血管神经机能症患者站卧两个体位的自主神经功能。结果显示：与正常人相比，心血管神经机能症患者站卧位的SDNN、HRVindex、RMSSD、PNN50、TP、LF、HF、HFnorm均低于正常人（P＜0．01）；而LF／HF、LFnorm高于正常人（P＜0．05）；正常人由卧位转为站位时，自主神经发生相应调节，表现交感神经活性增加，迷走神经活性降低。心血管神经机能症患者卧位变站位时HRV变化趋势与正常人基本相同，只是变化程度减小（LF／HF除外）。正常人SDNN、HRVindex、RMSSD、PNNS50、TP、LF、HFnorm与年龄呈负相关（P＜0．05）。心血管神经机能症患者除站位LF外，HRV各指标与年龄的相关比较均P＞0．05。     

食管心房调搏结合心率变异对窦房结功能的评估

生理状态下心脏的舒缩活动受窦房结的自律性控制 ,而窦房结的自律性活动受交感神经及迷走神经的支配。迷走神经对窦房结的调节作用反映在每一次窦性心动周期上 ,而交感神经的调节常常在 2 0s以后才起作用。心率 (HR)变异性 (HRV)是反映交感 迷走神经张力及其平衡的指标。本文通过HRV测定结合食管心房调搏 ,探讨HRV及电生理参数对评估窦房结功能的意义。1　对象与方法1 .1 　 对象受检对象分为 :①单纯窦性心动过缓 (窦缓 )组 :39例 ,男 2 2例 ,女 1 7例 ,年龄 38～ 63( 39.34±6.38)岁 ,临床无器质性心脏病和严重心律失常。②病态窦房…     

心血管神经调控的老年性改变

老年人与年轻人相比，静息状态的交感神经紧张性增高，心迷走神经紧张性高于心交感神经；对体位变换、深呼吸、咽鼓管、充气、寒冷、运动等体内外环境条件改变的应答性反应降低；窦房结的β－肾上腺素能受体密度减小。心率变化功率谱可用于无创性植物神经功能检测；老年人仰卧时颈脉窦按摩诱发的停跳时间可做为颈动脉综合征的诊断标准。     

低强度无创迷走神经刺激治疗冠状动脉慢血流患者的短期效果观察

目的 观察低强度无创迷走神经刺激（tragus stimulation,TS）对冠状动脉慢血流（coronary slow flow,CSF）患者的短期治疗效果。方法 选取2020年1月至2021年12月就诊于新疆医科大学第五附属医院心血管内科,行冠状动脉造影（coronary angiography,CAG）检查诊断为CSF的患者共60例,并随机分配为实验组（TS组,n=30）和对照组（N-TS组,n=30）,TS组给予无创迷走神经刺激30 min,N-TS组给予假刺激30 min,采用校正的心肌梗死溶栓治疗帧数计数（corrected TIMI frame count,CTFC）法计算刺激前后两组患者冠状动脉血流速度,记录其一般临床资料、生化指标以及术前、术后12导联心电图,同时分析干预前后心率变异性（heart rate variability,HRV）中频域成分低频功率（low frequency,LF）、高频功率（high frequency,HF）、LF/HF的变化。结果 TS组及N-TS组患者在一般情况、生化指标、刺激前各冠状动脉CTFC值、刺激前HRV中LF、HF、LF...     

正常人心率变异性的性别差异及生理节奏

检测60例正常人的24h心率变异性(HRV),分析性别、昼夜时辰的变化。表明代表交感神经和迷走神经活性平衡的参量LF/HF,女性显著低于男性,提示男性交感神经活性高于女性,和/或女性的迷走神经活性高于男性。夜间反映迷走神经活性的参量(如HF、rMSSD及pNN_(50))显著升高,与总功率密切相关的SDNN有较轻程度的下降。平均RR间期、rMSSD、pNN_(50)及SDNN有明显的时辰变化规律,起床后均显著降低。     

刺激犬心植物神经对心电功率谱的影响

在心电频域分析中，心电功率谱基波的大小约占心电总能量的１／３左右，而且基波所在的频率与心率一致，因而基波的大小是心电信号频域分析中一个重要指标。基波主要与心电图中Ｔ波和ＳＴ段相对应，与Ｐ波和ＱＲＳ关系不大。电刺激犬心迷走神经时，心率由刺激前的１８９±２７次／ｍｉｎ下降到１５５±３２次／ｍｉｎ（Ｐ＜０．０１）；Ⅱ导联基波大小由８５．２±４４．２下降到５２．７±４４．９（ｐ＜０．０１）。电刺激犬心交感神经时，心率由刺激前的１８７±２９次／ｍｉｎ上升到１９８±２７次／ｍｉｎ（Ｐ＜０．０１）；基波由６１．１±４５．８增加到９１．８±５７．５（ｐ＜０．０１）。电刺激犬右侧迷走神经引起基波下降的主要原因是由迷走神经负性变时作用引起的；电刺激犬左侧心交感神经引起基波增加的原因是心电综合向量增大所致。     

减慢呼吸频率对原发性高血压患者心率变异性和血压变异性的影响

目的观察减慢呼吸频率对原发性高血压患者心率、血压和心率变异性(HRV)和血压变异性(BPV)的影响。方法对60例原发性高血压患者进行16次/分、8次/分的均匀呼吸调节,同步记录呼吸、心电、血压波形,测量记录每次呼吸调节后即刻血压、心率。观察减慢呼吸频率对原发性高血压患者血压、心率、呼吸峰的影响;并用常规方法和校正方法(校正呼吸峰移位)分析对HRV、BPV高频功率(HF)、低频功率(LF)、LF/HF的影响。结果与呼吸频率16次/分比较,8次/分使血压降低(P0.001),心率减慢(P0.001),HRV和BPV的呼吸峰左移(P0.001);按常规方法分析,与呼吸频率16次/分比较,8次/分时HRV和BPV的HF减小,LF和LF/HF增大(除BPV的HF改变外,P均0.001);校正呼吸峰移位影响后,与呼吸频率16次/分比较,8次/分时HRV和BPV的HF增大,LF和LF/HF减小(P均0.001)。结论减慢呼吸频率可使原发性高血压患者血压降低,心率减慢,其机制为减慢呼吸频率增加了患者迷走神经张力,有助交感-迷走平衡移向迷走神经。     

Power Spectral Analysis of Cardiovascular Variability in Patients at Risk for Sudden Cardiac Death

Heart Rate Variability. The time series of successive heart periods present important variations around its mean value, determining the phenomenon of heart rate variability (HRV), assessed with both time and frequency domain approaches. A low standard deviation of the heart period (a time domain index of HRV) is a powerful prognostic indicator of sudden coronary death in patients recovering from acute myocardial infarction. Spectral analysis of HRV usually demonstrates two major components: indicated as LF (low frequency, ～ 0.1 Hz) and HF (high frequency, ～ 0.25 Hz). They are defined by center frequency and associated power, which is expressed in msec² or normalized units. When assessed in normalized units, LF and HF provide quantitative indicators of neural control of the sinoatrial node. Numerous experimental and clinical studies have consistently indicated that the LF component is a marker of sympathetic modulation and HF a marker of vagal modulation; the LF/HF ratio is a synthetic index of sympathovagal balance. In the analysis of 24-hour Holter recordings of normal subjects, a circadian rhythmicity of spectral markers of sympathetic and vagal modulation is clearly present, with a sympathetic predominance during the day and a vagal predominance during the night. In patients recovering from an acute myocardial infarction, spectral analysis of HRV revealed an increased sympathetic and decreased vagal activity during early convalescence, and a return to their normal balance by 6 to 12 months. A clear increase of LF was also evident in patients studied within a few hours of the onset of symptoms related to an acute myocardial infarction, independent of its location. Similarly, LF increased during transient myocardial ischemia. An increase in markers of sympathetic activity has also been observed prior to episodes of malignant arrhythmias. Spectral analysis of HRV could help in the understanding of the role of abnormal neural mechanisms in sudden coronary death, thus contributing to its prevention.     

迷走神经刺激术对癫痫病人心率变异性影响的Meta分析

目的系统评价迷走神经刺激术对癫痫病人心率变异性的影响。方法以“epilepsy”“vagal nerve stimulation”“heart rate variability”和“癫痫”“迷走神经刺激术”“心率变异性”等为检索词,检索中国知网(CNKI)、万方数据知识服务平台、Clinical Trials.gov、EMbase、PubMed、Cochrane Library、Web of Knowledge、FDA.gov等收录的相关研究,采用心率变异性的低频部分(LF)及高频部分(HF)作为评价指标,采用Newcastle-Ottawa Scale进行质量评价,采用RevMan 5.3进行Meta分析。结果纳入9篇文献,共122例施行迷走神经刺激术的癫痫病人。Meta分析结果显示,癫痫病人迷走神经刺激术前后LF值[SMD=-0.06,95%CI(-0.45,0.33),P=0.77]和HF值[SMD=-0.05,95%CI(-0.31,0.20),P=0.68]比较差异均无统计学意义。结论迷走神经刺激术前后癫痫病人的心率变异性无显著变化。     

Metabolic syndrome and short‐term heart rate variability in young adults

Aims Heart rate variability (HRV) can be used to estimate autonomic nervous control of the cardiovascular system. In middle‐aged subjects, the metabolic syndrome (MetS) is associated with lower HRV. We hypothesized that alterations in autonomic balance are already present in young adults with the MetS, and analysed the association of short‐term HRV with the MetS (using the National Cholesterol Education Program definition), in 1889 subjects aged 24–39 years. Methods Short‐term (3 min) HRV analysis included high‐frequency (HF), low‐frequency (LF) and total (TP) spectral components of HRV and LF/HF ratio. Results The presence of the MetS was associated with lower HF, LF and TP in men and women, and with higher LF/HF ratio in women. In men, waist circumference was the strongest individual MetS component that associated with HRV. After adjustments for age and heart rate, MetS was associated with lower HF and higher LF/HF ratio in women, but only with a lower TP in men (all P < 0.05). Conclusions MetS is associated with lower HRV in young adults. The individual components of MetS are differentially associated with HRV in men and in women. Our results are consistent with lower vagal activity and a possible increase in sympathetic predominance in women with the MetS. This sex difference in vagal activity and sympathovagal balance may partly explain the greater increase in cardiovascular risk associated with MetS in women than in men.     

乌拉坦麻醉深度与家兔心脏自主神经功能的关系

目的观察乌拉坦不同麻醉深度下家兔心脏自主神经功能的变化特征。方法应用心率变异性（HRV）分析确定静脉注射不同累积剂量乌拉坦（0.50、1.00、1.25、1.50、1.75、2.00、2.25、2.50 g/kg）对家兔自主神经的张力及均衡性的影响。结果时域成分:与剂量0.50 g/kg相比,心率在累积剂量1.25、1.50和1.75 g/kg时加快（P<0.05）,R-R间期在相应的3个剂量减小（P<0.05）;正常R-R间期的标准差在累积剂量1.00 g/kg之后减小（P<0.05或P<0.01）,R-R间期总变异在累积剂量1.25 g/kg之后减小（P<0.05或P<0.01）。频域成分:与剂量0.50g/kg相比,低频功率在累积剂量1.25、1.50、2.00、2.25和2.50 g/kg减小（各P<0.05）,但归一化低频功率无变化;高频功率（HF）在各累积剂量间无变化,但归一化高频功率在累积剂量1.25 g/kg之后均增大（P<0.05）;LF/HF在累积剂量1.00 g/kg之后显著减小（P<0.01）。结论乌拉坦麻醉过程中,家兔HRV降低的主要原因是心脏迷走副交感神经活性增加。     

Autonomic responses to single- and dual-chamber pacing

We investigated the autonomic effects of short-term, single- and dual-chamber pacing by evaluating frequency-domain indexes of heart rate variability (HRV). The study group comprised 25 patients (mean age 62 +/- 7 years) without organic heart disease and with normal sinus node function who were implanted with a permanent dual-chamber DDD (n = 16) or VDD (n = 9) pacing system for transient high-degree atrioventricular block. Continuous overdrive pacing for 15 minutes slightly above the intrinsic rhythm was programmed to ensure complete capture in AAI, DDD, and VVI modes, and the atrioventricular delays were set to ensure permanent ventricular pacing in DDD and VDD modes. Components of frequency-domain measures of HRV (low frequency [LF], high-frequency [HF], and LF/HF ratio) were calculated in 5-minute intervals over a 30-minute period after cessation of each pacing mode. AAI pacing did not significantly affect LF and LF/HF measures, and presented the highest HF power. DDD and VDD modes led to similar responses with slightly increased fluctuations of LF and LF/HF power. VVI pacing triggered an acceleration in heart rate (p <0.05), the most significant increases in LF power and in the LF/HF ratio, and the lowest HF power. Autonomic effects of pacing did not resolve with cessation of pacing. Atrial AAI pacing appears to have lesser effect on sympathovagal balance. Synchronous VDD and DDD stimulation favor a shift in autonomic balance toward sympathetic predominance. Asynchronous VVI pacing triggers both sympathetic overactivity and vagal withdrawal.     

The effect of sham feeding on neurocardiac regulation in healthy human volunteers.

BACKGROUND: Distension and electrical stimuli in the esophagus alter heart rate variability (HRV) consistent with activation of vagal afferent and efferent pathways. Sham feeding stimulates gastric acid secretion by means of vagal efferent pathways. It is not known, however, whether activation of vagal efferent pathways is organ- or stimulus-specific. OBJECTIVE: To test the hypothesis that sham feeding increases the high frequency (HF) component of HRV, indicating increased neurocardiac vagal activity in association with the known, vagally mediated, increase in gastric acid secretion. METHODS: Continuous electrocardiography recordings were obtained in 12 healthy, semirecumbent subjects during consecutive 45 min baseline, 20 min sham feeding (standard hamburger meal) and 45 min recovery periods. The R-R intervals and beat-to-beat heart rate signal were determined from digitized electrocardiography recordings; power spectra were computed from the heart rate signal to determine sympathetic (low frequency [LF]) and vagal (HF) components of HRV. RESULTS: Heart rate increased during sham feeding (median 70.8 beats/min, 95% CI 66.0 to 77.6; P<0.001), compared with baseline (63.6, 95% CI 60.8 to 70.0) and returned to baseline levels within 45 min. Sham feeding increased the LF to HF area ratio (median: 1.55, 95% C.I 1.28 to 1.77; P<0.021, compared with baseline (1.29, 95% CI 1.05 to 1.46); this increase in LF to HF area ratio was associated with a decrease in the HF component of HRV. CONCLUSIONS: Sham feeding produces a reversible increase in heart rate that is attributable to a decrease in neurocardiac parasympathetic activity despite its known ability to increase vagally mediated gastric acid secretion. These findings suggest that concurrent changes in cardiac and gastric function are modulated independently by vagal efferent fibres and that vagally mediated changes in organ function are stimulus- and organ-specific.     

Effects of cigarette smoking on ambulatory blood pressure,heart rate,and heart rate variability in treated hypertensive patients

We investigated the influence of cigarette smoking on the levels and circadian patterns of blood pressure (BP), heart rate (HR), and HR variability (HRV) in hypertensive patients. Sixteen hypertensive smokers (57 ± 2 years old) receiving antihypertensive treatments participated in this study. Ambulatory monitoring of BP, HR, and electrocardiograms was performed every 30 min for 24 hours on a smoking day and nonsmoking day in a randomized crossover manner. Average 24-hour BP and daytime BP were significantly higher in the smoking period than in the nonsmoking period. No significant differences were observed in nighttime BP between the two periods. Average 24-hour and daytime HR, but not nighttime HR, were also higher in the smoking period than in the nonsmoking period. The daytime high frequency (HF) component of HRV was attenuated more in the smoking period than in the nonsmoking period. No significant differences were observed in the low frequency (LF) components of HRV or LF/HF ratio between the two periods. These results demonstrated that cigarette smoking increased the daytime and average 24-hour BP and HR, and the increases observed in daytime BP and HR were associated with the attenuation of parasympathetic nerve activity.     

Cardiovascular Autonomic Function in Conscious Rats: A Novel Approach to Facilitate Stationary Conditions

Background An experimental setting and software were developed to evaluate cardiovascular autonomic function in conscious rats. A restrained approach was used, which, upon proper habituation, induced little or no stress in the rats and limited motion artifacts. Methods: The ECG and arterial blood pressure were recorded. Time‐ and frequency‐domain indices of heart rate variability (HRV) and blood pressure variability (BPV) were calculated. The spontaneous baroreflex sensitivity (spBRS) was estimated using the method of statistical dependence. Results: The power spectra clearly concentrated in a frequency band with center frequency around 0.4 Hz, the low frequency (LF) component, and one at the respiratory frequency at 1.5 Hz, the high frequency (HF) component. In baseline conditions, a direct association existed between mean R‐R and especially HRV parameters denoting vagal modulation such as rMSSD, pNN5, and HF power. Beta‐adrenergic blockade by propranolol diminished basal heart rate. Vagal indices increased while there was an exclusive decrease in the low frequency band of HRV. Alpha‐adrenergic blockade with phentolamine produced a depressor response with tachycardia, and a clear decrease in the LF component of BPV. Both the LF and HF component in the HRV spectrum were virtually absent. Cholinergic blockade with atropine did not significantly alter BP but induced a clear tachycardia with decreased vagal indices. The HF component of HRV was completely abolished and the LF band was reduced. Conclusions: Both a‐ and 13‐adrenergic blockade left 5pBRS virtually unaltered, while cholinergic blockade profoundly diminished spBRS. Spectral fluctuations of 13‐sympathetic tone were restricted to the LF range of HRV, while the HF respiratory component represented vagal modulation. The a‐sympathetic system played a dominant role in the LF oscillations of BPV. A role of the vagus in the HF oscillations of BPV in the rat is questioned. The baroreflex depended mainly on changes in vagal activity. A.N.E. 2002;7(4):307–318     

Long-Term follow-up of the circadian rhythm of heart rate and heart rate variability in healthy elderly patients.

BACKGROUND: The long-term age-related changes in circadian rhythm of heart rate variability (HRV), that is, autonomic nervous activity, remain unknown in elderly people. METHODS AND RESULTS: Holter monitoring was conducted twice at an interval of 15 years in 15 healthy elderly patients (age: 70.0 +/- 4.1 years, at first monitoring, female: 10) and assessed the age-related changes in 24-h mean and hourly mean normal sinus R-R interval (mean NN), HRV (high frequency (HF) component, low frequency (LF) component and LF/HF) and the circadian rhythms. As a result, 24-h mean mean NN (0.976 +/- 0.115 vs 0.903 +/- 0.117 (s), p = 0.0019), LF/HF (1.681 +/- 0.731 vs 0.962 +/- 0.442, p = 0.0022), and LF (278.88 +/- 176.43 vs 179.19 +/- 132.33 (ms2), p = 0.0039) significantly decreased 15 years later, although 24-h mean HF (221.20+/-138.89 vs 310.78+/-296.73 (ms2), p = 0.1102) increased slightly. The hourly mean NN closely correlated with hourly HF and LF/HF throughout circadian rhythms both at first and second monitoring. In the morning hours, amplitude rates of all HRV indices increased significantly 15 years later. CONCLUSION: In elderly people, age-related changes in the 24-h mean heart rate (HR) were conversely dissociated from those of the 24-h mean HRV. However, the close correlation between hourly HR and HRV was preserved, even in very elderly patients. Additionally, the amplitude rates in HRV in the morning increased with age. These age-related changes of HR and HRV might be characteristic of elderly people.     

苯那普利对高血压病患者心率变异性及其昼夜节律的影响

目的　观察苯那普利对高血压病患者动态血压、心率变异性及其心率变异性昼夜节律的影响。方法　 3 6例高血压病人 ,服用苯那普利 ( 10～ 2 0 mg/ d) 8周 ,用药前后做动态血压和 2 4h动态心电图分析。结果　治疗后动态血压各指标均下降 ( P<0 .0 5或 <0 .0 1) ;HRV(心率变异性 )时域指标 RMSSD(全部相邻 RR间期之差的均方根值 )升高 ( P<0 .0 5 ) ,其他指标虽均有升高 ,但无统计学意义 ( P>0 .0 5 ) ;频域指标中 HF(高频功率 )增加 ,L F(低频功率 )、L F/ HF下降 ;5分钟 HRV中治疗后白昼段和夜间段 HF均升高 ,L F/ HF均下降 ,且白昼段 L F较夜间段高 ,HF比夜间段低。结论　苯那普利可以很好控制全天血压 ,同时降低交感神经活性 ,提高迷走神经张力 ,且不干扰心率变异性的昼夜节律