慢性心衰患者QT离散度：β-受体阻滞剂和QT离散度减少有关

目的　临床和电生理研究表明 ,心肌复极化不均对产生室性心律失常非常重要。 QT离散度是心肌复极化离散的有效指标。本文研究的目的是对左室收缩功能减损的患者和左室收缩功能正常的对照组患者 QT离散度进行比较。方法　对疑有心衰经 M型超声心电图检查 5 3 4份既往病历进行回顾性分析。按左室收缩功能是否减损分两组 ,每组均除去有心房颤动 ,左右束支传导阻滞 ,心电图左室肥厚或左室高电压的患者 ,有左室收缩功能减损 2 5例及正常2 0 2例。2 0 2例左室收缩功能正常的患者 ,按年龄、性别、先前心肌梗塞 ,利尿剂和β-受体阻滞剂治疗 ,与 2 …     

QT离散度与急性心肌梗塞合并室性心律失常的关系

对40例急性心肌梗塞伴室早或室速者检测QT离散度（QTd），结果显示正常组QTd19．2±62ms，急性心梗室早组58．4±22．6ms，急性心梗室速组QTd100±26．1ms。两组甲襞微循环均有明显异常改变。提示检测QTd对预测急性心梗时是否合并严重定性心律失常有价值，微循环异常改变参与了疾病的发病过程。     

QT离散度的临床研究进展

QT离散度（QTd）是指标准12导联心电图中最大QT间期与最小QT间期之差。1990年Day和Campbell^[1]等首先提出QT离散度的概念。认为QTd反映了心室复极的不一致性和心电的不稳定性。随后的大量实验及临床研究报告了QTd的生理学意义及临床应用价值,并将其作为反映心室复极的不均一性的一种无创伤性指标,广泛应用于心脏的各种病理状态及抗心律失常药物的评价,受到越来越多的关注和重视。     

去心交感神经对QT离散度的影响

目的：采用动物实验方法，观察去心交感神经对QT离散度（QTd）的影响，并观察QT离散度的昼夜节律变化，以探讨QT离散度变化的电生理基础。 方法： 以新西兰兔作为实验对象，实验组手术去除心交感神经支配，对照组手术保留心交感神经支配。观察两组手术前后QTd变化及24 h内QTd的昼夜变化。 结果： 实验组在手术后QTd显著减小(P＜0.05)，对照组在手术前后QTd无显著变化（P＞0.05）；实验组在手术后24 h内QTd始终低于对应的对照组，且无明显节律变化，对照组在24 h内QTd呈现出显著的昼夜节律变化。 结论： 心交感神经活动可能是产生QTd的机制之一。     

高血压伴左室肥厚的QT离散度分析

目的：研究原发性高血压伴左室肥厚的左室重量（LVM）对QT间期离散度（QTd）的影响及QTd对室性心律失常的预测作用。方法：检测146例患者的QT、JT、OTc、JTc离散度和超声心动图，其中98例行24h动态心电图监测。结果：原发性高血压的复极离散度大小与左室重量呈正相关，伴左室肥厚者（LVH组）的QTd大于无左室肥厚者（对照组）（P〈0．01），有持续性室速发生者（SVT组）的复极离散度大于无室性心律失常者（对照组）（P〈0．01），仅有室性期前收缩者（VPC组）的QTd与对照组无明显差异（P〉0．05）。结论：复极离散度的大小主要与左室重量有关，伴左室肥厚者的心性猝死率增加可能与QTd的增大有关，QTd的变化可作为原发性高血压恶性室性心律失常的预测指标。     

QT离散度对新生儿缺氧缺血性心肌损伤的诊断价值

心电图对缺氧缺血性心肌损伤具有确切的诊断价值 ,为人们诊断心肌缺血坏死提供了简便而可靠的方法。自体表心电图应用于临床以来 ,人们即发现心电图不同导联ＱＴ间期间存在着差异 ,但一直被认为是测量的伪差而未引起重视。虽早在 1985年Ｃａｍｐｂｅｌｌ等即发现不同导联间ＱＴ间期的差异具有一定规律性 ,并提出了ＱＴ离散度 (ＱＴｄ)的概念 ;但直到 1990年Ｄａｙ等才证实ＱＴｄ具有重要的临床价值[1] 。从此 ,ＱＴｄ在临床上得到了广范的应用。我们从 1995年起引用ＱＴｄ评价窒息新生儿缺氧缺血性心肌损伤 ,发现是一种特异而敏感的指标 ,本…     

心力衰竭患者血液粘度与QT间期离散度的关系

目的探讨心力衰竭患者血液粘度与QT离散度 (QTd)关系。方法十二道同步自动分析心电图机测定58例心力衰竭患者QTd ,按QTd大小分组 ,QTd≥50ms组 ,QTd<50ms组。检查两组的全血粘度 ,并进行比较。结果QTd≥50ms组较QTd<50ms组的全血粘度 (低切 )、红细胞聚集指数明显增高 ,具有显著性意义 (P<0.05～0.01)。结论心力衰竭患者QTd增加与全血粘度有关。降低血粘度可能有助降低QTd ,对防止QTd增加导致心律失常有意义     

QT离散度与高血压左室肥厚的关系探讨

目的探讨高血压并左室肥厚与QT 离散度(QT dispersion,QTd)、心室晚电位(Ventricular late potent ial, VLP)之间的联系及其临床意义.方法 108例高血压患者分为LVH组与非LVH组.均测QTd及VLP.LVH组接受比索洛尔治疗2个月,并比较治疗前后QTd及VLP情况.结果①LVH组与非LVH组VLP阳性检出率与QTd差异具有显著性;②LVH组治疗后VLP阳性检出率与QTd均较治疗前降低(p＜0.05).结论 QTd及VLP可成为早期检测高血压并LVH患者重要指标,以便及时采取措施预防严重心律失常事件发生.     

QT离散度及其临床意义

ＱＴ离散度及其临床意义冯生杰１综述贾国良２审校１解放军第四六零医院心内科（４５０００７）２第四军医大学西京医院心内科（７１００３２）１９８５年Ｃａｍｐｂｅｌ等［１］发现心电图（ＥＣＧ）不同导联间ＱＴ间期的差异有其规律性，因而提出了ＱＴ离散度（ＱＴｄｉ...     

QT离散度与高血压左室肥厚的关系探讨

目的 探讨高血压并左室肥厚与QT离散度（QT dispersion，QTd）、心室晚电位（Ventrieular late potent ial，VLP）之间的联系及其临床意义。方法 108例高血压患者分为LVH组与非LVH组。均测QTd及VLP。LVH组接受比索洛尔治疗2个月，并比较治疗前后QTd及VLP情况。结果 ①LVH组与非LVH组VLP阳性检出率与QTd差异具有显著性；②LVH组治疗后VLP阳性检出率与QTd均较治疗前降低（p〈0．05）。结论 QTd及V1P可成为早期检测高血压并LVH患者重要指标，以便及时采取措施预防严重心律失常事件发生。     

Ageing,the autonomic nervous system and arrhythmia: From brain to heart

An ageing myocardium possesses significant electrophysiological alterations that predisposes the elderly patient to arrhythmic risk. Whilst these alterations are intrinsic to the cardiac myocytes, they are modulated by the cardiac autonomic nervous system (ANS) and consequently, ageing of the cardiac ANS is fundamental to the development of arrhythmias. A systems-based approach that incorporates the influence of the cardiac ANS could lead to better mechanistic understanding of how arrhythmogenic triggers and substrates interact spatially and temporally to produce sustained arrhythmia and why its incidence increases with age. Despite the existence of physiological oscillations of ANS activity on the heart, pathological oscillations can lead to defective activation and recovery properties of the myocardium. Such changes can be attributable to the decrease in functionality and structural alterations to ANS specific receptors in the myocardium with age. These altered ANS adaptive responses can occur either as a normal ageing process or accelerated in the presence of specific cardiac pathologies, such as genetic mutations or neurodegenerative conditions. Targeted intervention that seek to manipulate the ageing ANS influence on the myocardium may prove to be an efficacious approach for the management of arrhythmia in the ageing population.     

Localisation and quantitation of autonomic innervation in the porcine heart II: endocardium, myocardium and epicardium

The immunological problems of pig hearts supporting life in human recipients have potentially been solved by transgenic technology. Nevertheless, other problems still remain. Autonomic innervation is important for the control of cardiac dynamics and there is evidence suggesting that some neurons remain intact after transplantation. Previous studies in the human heart have established regional differences in both general autonomic innervation and in its component neural subpopulations. Such studies are lacking in the pig heart. Quantitative immunohistochemical and histochemical techniques were used to demonstrate the pattern of innervation in pig hearts (Sus scrofa). Gradients of immunoreactivity for the general neural marker protein gene product 9.5 were observed both within and between the endocardial, myocardial and epicardial plexuses throughout the 4 cardiac chambers. An extensive ganglionated plexus was observed in the epicardial tissues and, to a lesser extent, in the myocardial tissues. The predominant neural subpopulation displayed acetylcholinesterase activity, throughout the endocardium, myocardium and epicardium. These nerves showed a right to left gradient in density in the endocardial plexus, which was not observed in either the myocardial or epicardial plexuses. A large proportion of nerves in the ganglionated plexus of the atrial epicardial tissues displayed AChE activity, together with their cell bodies. Tyrosine hydroxylase (TH)-immunoreactive nerves were the next most prominent subpopulation throughout the heart. TH-immunoreactive cell bodies were observed in the atrial ganglionated plexuses. Endocardial TH- and NPY-immunoreactive nerves also displayed a right to left gradient in density, whereas in the epicardial tissues they showed a ventricular to atrial gradient. Calcitonin gene-related peptide (CGRP)-immunoreactive nerves were the most abundant peptide-containing subpopulation after those possessing NPY immunoreactivity. They were most abundant in the epicardial tissues of the ventricles. Several important differences were observed between the innervation of the pig heart compared with the human heart. These differences may have implications for the function of donor transgenic pig hearts within human recipients.     

低体温与心率变异性和血压变异性的关系

目的: 研究低体温与自主神经功能变化的关系。方法: 采用体表物理降温法逐步降低直肠温度,直肠温度变化范围为19-37 ℃。分别记录不同直肠温度下大鼠动态心电和血压信号。应用心率变异性和血压变异性分析系统评价低体温对心率变异性和收缩压变异性的影响。结果: 心率变异分析表明，直肠温度下降到29 ℃以下,R-R间期均延长（P<0.01）,提示心率明显降低;当直肠温度下降到19-21 ℃时,心率变异归一化低频功率降低（P<0.05）和归一化高频功率增加（P<0.05），而且自主神经的平衡向心迷走神经张力增强的方向发生了转移（P<0.05）。血压变异性分析表明，体温下降到31℃时与呼吸有关的归一化高频功率开始增加（P<0.01）；直肠温度下降到29 ℃以下(除27 ℃外),与呼吸有关的归一化高频功率增加（P<0.05或P<0.01），同时自主神经的平衡也发生了改变（P<0.05）。结论： 随着体温的降低，心血管迷走神经活性增加，自主神经的平衡向迷走神经张力增强的方向转移。低体温对血压变异性的影响敏感于心率变异性。     

氯化铯所致在体家兔早期后除极及复极离散化在多形性室速中的意义

目的和方法：本文采用浮置式玻璃微电极记录心肌细胞跨膜动作电位（ＴＡＰ）技术，研究氯化铯（ＣｓＣｌ）诱发的在体家兔早期后除极（ＥＡＤ）和触发电活动（ＴＡ）以及复极离散化程度。结果：ＣｓＣｌ诱发高膜电位水平的ＥＡＤ的配对间期（ＣＩ）较长，其振幅和ＣＩ随刺激周期（ＣＬ）的增加而增加，此种ＥＡＤ及ＴＡ可导致室性早搏（ＶＰＢ）和多形性室速，ＥＡＤ的ＣＩ和ＶＰＢ的ＣＩ几乎相等（ｒ＝０．８９）。ＣｓＣｌ诱发低膜电位水平的ＥＡＤ的ＣＩ较短，其振幅和ＣＩ不随ＣＬ的改变而发生变化，此种ＥＡＤ及ＴＡ可导致短ＣＩ的插入性ＶＰＢ。ＣｓＣｌ还可增加心壁中的不同区域之间的复极离散化趋势，其原因是由于动作电位时程的差异的增加。结论：为ＣｓＣｌ导致的室性心动过速系由于心动过缓依赖性的ＥＡＤ及ＴＡ所致的学说提供了直接证据。明显的动作电位时程的差异可能在心动过速的维持过程中发挥作用。     

QT dispersion in the surface electrocardiogram in elderly patients with major depression

Background: QT dispersion (QTd) is a measure of interlead variations of QT interval of the surface 12-lead electrocardiogram (ECG). Increased QTd, found in various cardiac diseases, reflects cardiac instability and is associated with increased cardiac death. Major depressive disorder (MDD) was found to be associated with high cardiovascular mortality rates. This study compares QTd in elderly patients with MDD to normal controls. Methods: QTd and rate-corrected QTd of 18 physically healthy elderly patients (69.9±7.6 years) with MDD was compared to nine physically and mentally healthy age- and gender-matched controls (64.1±12.2 years). Results: QTd and rate-corrected QTd were significantly higher in MDD compared to controls (68±30 vs. 40±13 ms, P=0.002 and 81±39 vs. 43±13 ms, P=0.001, respectively). Intra- and inter- observer reproducibilities were highly correlated (r=0.96, P <0.0001; r=0.88, P <0.001, respectively). Limitations and Conclusions: The major limitations of this study are the small number of subjects and the fact that all the patients were maintained on antidepressant medication. However, it seems that QTd analysis might shed light on possible autonomic imbalance and also provide a novel cardiovascular risk factor for increased cardiac death in MDD.     

调节自主神经系统:心血管疾病抗炎治疗的新领域

<正>目前普遍认为高血压、动脉粥样硬化、血脂异常、糖尿病等疾病的发生、发展和转归与炎症免疫反应有着密切联系。同时,心血管疾病中也伴有自主神经病变,表现为交感神经和迷走神经支配紊乱或结构损伤,其主要的病理特征是迷走神经张力减低而交感神经张力亢进。因此,改善自主神经紊乱同时减轻机体低度炎症反应将成为防治心血管疾病的重要方向。近60年的研究表明神经系统可接受免疫系统信号,并可传出神经冲动调节免疫系统活动。     

Consistency of heart rate and sympathovagal reactivity across different autonomic contexts

Theories that psychophysiological reactivity constitutes a risk factor for coronary artery disease assume that reactivity is a consistent individual characteristic. We tested this assumption by measuring reactivity to three psychologically challenging tasks performed by 22 healthy subjects across different autonomic contexts produced by positional change. Dependent variables included heart rate (HR), low-frequency (LF; 0.04–0.15 Hz) and high-frequency (HF; 0.15–0.50Hz) heart period variability, and the LF/HF ratio. HR (r= .44, p < .05) and LF/HF ratio (r= .48, p= .03) reactivity were modestly correlated across the different autonomic contexts, but HF and LF power reactivity were not. These findings suggest that HR reactivity to psychological challenge is a modestly consistent characteristic of individuals, despite differences in autonomic context. Although the same is true of cardiac sympathovagal balance, reactivity of HF and LF power were less consistent.     

Correlation between heart rate variability and pulmonary function adjusted by confounding factors in healthy adults

The autonomic nervous system maintains homeostasis, which is the state of balance in the body. That balance can be determined simply and noninvasively by evaluating heart rate variability (HRV). However, independently of autonomic control of the heart, HRV can be influenced by other factors, such as respiratory parameters. Little is known about the relationship between HRV and spirometric indices. In this study, our objective was to determine whether HRV correlates with spirometric indices in adults without cardiopulmonary disease, considering the main confounders (e.g., smoking and physical inactivity). In a sample of 119 asymptomatic adults (age 20-80 years), we evaluated forced vital capacity (FVC) and forced expiratory volume in 1 s (FEV₁). We evaluated resting HRV indices within a 5-min window in the middle of a 10-min recording period, thereafter analyzing time and frequency domains. To evaluate daily physical activity, we instructed participants to use a triaxial accelerometer for 7 days. Physical inactivity was defined as <150 min/week of moderate to intense physical activity. We found that FVC and FEV₁, respectively, correlated significantly with the following aspects of the RR interval: standard deviation of the RR intervals (r =0.31 and 0.35), low-frequency component (r =0.38 and 0.40), and Poincaré plot SD2 (r =0.34 and 0.36). Multivariate regression analysis, adjusted for age, sex, smoking, physical inactivity, and cardiovascular risk, identified the SD2 and dyslipidemia as independent predictors of FVC and FEV₁ (R ²=0.125 and 0.180, respectively, for both). We conclude that pulmonary function is influenced by autonomic control of cardiovascular function, independently of the main confounders.     

Relations between psychometric profiles and cardiovascular autonomic regulation in physical education students

This study was designed to investigate physical education (PE) students the link between mood disturbances, caused by psychological or physical stressors associated with studying, and the autonomic nervous system modifications. PE students completed the profile of mood state (POMS) questionnaire at the end of the university year. Heart rate variability (HRV) was then measured during a head-up tilt test (HUT) in those with the highest and lowest total mood disturbance (TMD) scores on three successive POMS. Among the 218 students who completed the POMS (85 female and 137 male), 65 had high TMD scores, suggesting mood disturbances and fatigue. The final sample included 12 subjects in the potentially overtrained (POT) group and 16 subjects in the control (CTL) group. A greater decrease of two indices of the autonomic system (SD1 and RMSSD) was observed during the HUT in the POT than in the CTL group (P < 0.05). The depression (Dep) and vigor (Vig) subscales of POMS were correlated with several HRV indices. More specifically, in the POT group, the Vig score was correlated with autonomous activity in the supine position, and the Dep score with percentages of change of sympatho-vagal activity during the HUT. This suggests that (1) POT students could present a weaker autonomic response to HUT, (2) Dep and Vig subscales of the POMS questionnaire may indicate autonomic dysregulations.     

Feelings and the body: The Jamesian perspective on autonomic specificity of emotion

“What is an emotion?” William James's seminal paper in Mind (1884) proposed the idea that physiological and behavioral responses precede subjective experience in emotions that are marked by “distinct bodily expression.” This notion has broadly inspired the investigation of emotion-specific autonomic nervous system activity, a research topic with great longevity. The trajectory of this literature is traced through its major theoretical challenges from the Cannon-Bard, activation, and Schachter-Singer theories, through its rich empirical history in the field of psychophysiology. Although these studies are marked by various findings, the overall trend of the research supports the notion of autonomic specificity for basic emotions. The construct of autonomic specificity continues to influence a number of core theoretical issues in affective science, such as the existence of basic or ‘natural kinds’ of emotion, the structure of affective space, the cognition-emotion relationship, and the function of emotion. Moreover, James's classic paper, which stimulated the emergence of psychology from philosophy and physiology in the latter nineteenth century, remains a dynamic force in contemporary emotion research.