陈旧性心肌梗死患者心率震荡与恶性心律失常的关系

目的：通过动态心电图分析陈旧性心肌梗死患者心率震荡参数与恶性心律失常的关系。方法：选取45例陈旧性心肌梗死患者及100例正常对照组进行动态心电图检测,分析其心率震荡参数及室性心律失常情况,并根据室性心律失常的发生与否将心肌梗死组分为A组（室性心动过速组）与B组（无室性心动过速组）,比较其心率震荡参数的统计学差异。结果：心肌梗死组患者震荡初始（TO）为-0.46±1.37,震荡斜率（TS）为3.99±3.53;正常对照组TO为-1.93±1.86,TS为8.98±4.84;心肌梗死A组与B组的TO分别为0.32±2.01及-0.91±1.80,TS分别为2.75±3.33及5.32±3.89。心肌梗死组与对照组心肌梗死A组与B组的心率震荡参数均有显著差异。结论：陈旧性心肌梗死患者的心率震荡指数低于正常人,与室性心律失常的发生有关,作为恶性心律失常的预测因子,有一定的临床价值。     

心肌梗死后心率变异减低与室性心律失常的关系

已发现心肌梗死(MI)后出现自主神经系统功能失调和神经内分泌紊乱[1],且与心脏事件密切相关[2].采用动态心电图(AECG)时域法对陈旧性心肌梗死(OMI)患者进行心率变异(HRV)分析及室性心律失常观察,探讨MI后长期HRV异常与室性心律失常的关系及其意义.     

室性心律失常患者心率变异的临床意义及护理

为了探讨室性心律失常心率变异(HRV)的临床意义,对59例Lown氏分级Ⅲ级以上的室性心律失常患者和84例正常人进行了24h动态心电图记录。结果,比较两组正常R-R间期的标准差、全程记录中每5minR-R间期平均值的标准差、全程记录中每5minR-R间期标准差的平均值均有非常显著差异(P<0.001);相邻正常R-R间期差值的均方根、相邻正常R-R间期差值大于50ms记数占总数R-R间期数的百分比均有显著性差异(P<0.05)。说明心率变异可以作为观察室性心律失常患者病情的指标,对指导临床实施恰当的护理非常重要。     

冠心病患者心率和心率变异及室性心律失常的探讨

回顾冠心病患者40例,将其作为试验组,选取20例身体健康者作为对照组,观察两组研究对象的室性心律失常发生情况,比较两组研究对象的均值标准差(SDANN)、总体标准差(SDNN)、24h每5minR-R间期标准差的平均值(SDNN index)、相邻R-R间期差50ms的百分数(PNN50)。无论是SDNN、SDANN,还是SDNN index、PNN50,与对照组相比,试验组患者的数值较低,两组数据具有显著差异,存在统计学意义(P0.05)。与身体健康者相比,冠心病患者的自主神经功能较弱,更容易出现室性心律失常。     

中药干预对成人心肌炎患者窦性心率震荡及血清心肌损伤指标的影响

目的探讨中药干预对成人心肌炎患者窦性心率震荡及血清心肌损伤指标的影响。方法采用随机数字表法将患者分为研究组、对照组，对照组患者进行常规西药治疗，研究组除进行常规内科治疗外，还辅以参松养心胶囊、丹红注射液治疗。于入组时及治疗15d后分别对心电图窦性心率震荡（HRT）、及血清心肌肌钙蛋白T（cTnT）、高敏C反应蛋白（hs—CRP）、肌酸激酶同功酶（CK—MB）进行测评，并比较治疗15d后的临床疗效。结果两组治疗后震荡初始（TO）值均显著降低，而震荡斜率（TS）值均显著增加（P〈0．05）；治疗后研究组TO、TS值变化更明显（P〈0．01）。两组治疗后血清cTnT、hs—CRP、CK—MB水平均显著降低，较治疗前均差异有显著统计学意义（P〈0．01），血清cTnT、hs．CRP、CK-MB水平治疗后研究组降低更明显（P〈0．01）。治疗15d后两组心电图改善情况、临床症状改善情况研究组显著好于对照组（P〈0．05）。结论采用中药参松养心胶囊、丹红注射液干预成人心肌炎的治疗，较单用常规西药者，能更有效地改善HRT指标，降低血清cTnT、hs—CRP、CK—MB水平。     

原发性高血压并冠心病心率变异性与室性心律失常的关系

目的：探讨原发性高血压（EH）合并冠心病（CHD）心率变异性（HRV）与室性心率失常的关系。方法：30例EH患者（EH组）、40例EH合并CHD患者（EH合并CHD组）及20例健康体检者（对照组）行24hECG监测。观察3组室性心律失常发生情况。结果：EH合并CHD组SDNN、SDANN、SDNNindex、rMSSD及PNNS0均明显低于对照组（P均〈0．01），室早总发生率、24h室早总次数和LownⅢ级以上室早发生率明显高于对照组（P〈0．005，P〈0．01）。结论：高血压合并冠心病患者自主神经功能受损严重，这类患者更易出现复杂室性心律失常。     

病毒性心肌炎患者病程中心脏自主神经功能与心律失常关系的动态研究

目的:探讨病毒性心肌炎患者病程中心脏自主神经功能与心率变异性(heart rate variabili.ty,HRV)、心律失常发生率的动态关系.方法:测定96例急性病毒心肌炎在病程不同阶段(1、3、6个月)的心脏自主神经功能,同时通过动态心电图分析HRV以及各种心律失常的发生情况.结果:①病毒性心肌炎患者病程第1个月内自主神经功能检查有1项或1项以上异常者占58%(56/96),到6个月时,仅占17%,前后比较P＜0.01;②HRV时域法分析以24小时内5分钟节段正常R-R间期标准差的平均数及连续正常R-R间期之差的均方根值在疾病初期(1个月时)明显减少,随着时间推移逐渐恢复,到6个月时与1个月比较P＜0.01,HRV能谱分析在疾病初期总能谱、低能谱及高能谱均减低,6个月时增高,前后比较总能谱、低能谱均为P＜0.01,高能谱为P＜0.05;③按自主神经功能检查结果阳性与阴性分为两组,疾病初期阳性组的窦性心动过速、频发室性期前收缩、二联律、成对室性期前收缩及短阵室性心动过速的发生率均高于阴性组(均为P＜0.05);6个月时随着心脏自主神经功能及HRV的恢复两组差异均无统计学意义,与1个月时比较各种心律失常的发生率明显减少(均为P＜0.05).结论:①急性病毒性心肌炎患者疾病早期(1个月内),自主神经功能受损较明显,同时伴随24小时内5分钟节段正常R-R间期标准差的平均数及连续正常R-R间期之差的均方根值、总能谱、低能谱及高能谱的降低,各种心律失常的发生率较高;②病程6个月时,自主神经功能紊乱以及HRV的异常明显改善,各种心律失常的发生率明显减少.提示病毒性心肌炎急性期内(6个月)心电属不稳定阶段,强调限制运动、适当休息及相应处理的重要性,如不发生病毒再感染,6个月后安全性明显增高.     

冠心病发作性心肌缺血患者心率变异性与室性心律失常及其相关性

诸多研究表明心率变异性(HRV)是预测心脏严重事件发生的重要指标,并证实冠心病患者HRV较正常人显著下降,同时又有研究认为HRV下降使室性心律失常发生的机会增多。但冠心病患者发作性心肌缺血对HRV和室性心律失常的影响以及其相互关系如何,尚报道较少。本文通过对75例冠心病患者动态心电图结果的分析,旨在探讨发作性心肌缺血、HRV及室性心律失常三者的相互关系。     

Heart Rate Turbulence Impairment and Ventricular Arrhythmias in Patients with Systemic Sclerosis

Background: Arrhythmias, conduction disturbances, and cardiac autonomic nervous system dysfunction are the most frequent cardiovascular complications in systemic sclerosis (scleroderma). The aim of the study was to assess heart rate turbulence (HRT) in systemic sclerosis patients and to identify the relationship between HRT and occurrence of arrhythmias. Methods: Forty‐five patients with scleroderma (aged 54.6 ± 14.7 years) and 30 healthy sex‐ and age‐matched subjects were examined. In addition to routine studies, 24‐hour Holter monitoring with assessment of HRT was performed. Results: As compared to controls, HRT was significantly impaired in systemic sclerosis patients. Abnormal HRT defined as turbulence onset (TO) ≥0.0% and/or turbulence slope (TS) ≤2.5 ms/RR (ms/RR interval) was found in 19 (42%) scleroderma patients and in no members of the control group. Serious ventricular arrhythmias Lown class IV (VA‐LownIV), for example, couplets and/or nonsustained ventricular tachycardias, were observed in 16 (36%) scleroderma patients. The median value of TS was significantly lower in systemic sclerosis patients with VA‐LownIV than in patients without VA‐LownIV (3.68 vs 7.00 ms/RR, P = 0.02). The area under curve of ROC analysis for prediction of VA‐LownIV was 0.72 (95% confidence interval [CI] 0.56–0.87) and revealed that TS <9.0 ms/RR was associated with VA‐Lown IV occurrence, with sensitivity of 93.7% and specificity of 44.8%. Univariate and multivariate analyses confirmed that lower values of TS were associated with VA‐LownIV occurrence (odds ratio 1.52, 95% CI 1.09–2.12, P = 0.01). Conclusions: Patients with systemic sclerosis are characterized by significant HRT impairment. Assessment of HRT and especially TS is useful in the identification of patients at risk for ventricular arrhythmias. (PACE 2010; 920–928)     

窦性心率震荡评估冠心病病人预后的价值研究

目的观察冠心病（CHD）病人窦性心率震荡（HRT）的特征,明确其对CHD病人发生心脏不良事件的预测价值。方法选择年龄、性别相匹配的CHD病人（CHD组）和健康体检者（对照组）各60例,均进行24 h心电图（Holter）检查,对2组HRT的2个指标：震荡初始（TO）和震荡斜率（TS）进行比较。并对CHD病人进行6-12个月跟综随访,了解心脏不良事件（心肌再梗死、再发心绞痛、恶性心律失常、心脏猝死）的发生情况。结果与对照组比较,CHD组TO增高,为（1.08±0.27）%vs（0.18±0.33）%,TS减小,为（3.12±0.87）ms·RRI^-1vs（6.51±0.63）ms·RRI^-1（均P〈0.05）;CHD组中不良事件组TO高于非不良事件组,TS低于非不良事件组（均P〈0.05）。结论CHD病人HRT减弱,而发生心脏不良事件的病人HRT减弱更严重。HRT可作为CHD病人预后的一个评估指标。     

Heart Rate Turbulence in Chagas Disease

RIBEIRO, A.L.P., et al. : Heart Rate Turbulence in Chagas Disease. Heart rate turbulence (HRT) quantifies the biphasic response of the sinus node to ventricular premature complexes (VPCs) and is a powerful electrocardiogram related risk predictor. VPCs are frequent in Chagas disease, a potentially lethal illness, and can hamper the analysis by conventional methods of autonomic heart control. The aim of the study was to examine HRT in patients with Chagas disease. Chagas disease patients and healthy controls (group   0, n = 11   ) without other diseases were submitted to a standardized protocol, including electrocardiogram, echocardiography, and 24-hour Holter monitoring. Chagas disease patients were divided according to their left ventricular systolic function: normal (group   1, n = 103   ) and reduced ejection fraction (group   2, n = 23   ). Two HRT indices, turbulence onset (TO) and turbulence slope (TS), were calculated and compared among groups after adjustment for covariates like the prevalence of VPCs and the mean heart rate. Chagas disease patients had significantly altered TO (group 1: −0.0186, group 2: −0.0126) and TS (group 1: 10.844, group 2: 7.870) values in comparison with controls (TO − 0.0256, TS 19.829);   P < 0.001   for both comparisons. In conclusion, HRT data may be useful in the electrocardiographic analysis of autonomic heart control in Chagas disease. Its prognostic value remains to be determined. (PACE 2003; 26[Pt. II]:406–410)     

慢性心力衰竭患者心率震荡起始时间分析

目的：研究窦性心率震荡（HRT）的新测量指标震荡斜率起始时间（TT）及HRT测量指标震荡初始（TO）、震荡斜率（TS）在慢性心力衰竭（CHF）患者中的变化,并分析各指标与年龄、室性早搏前心率、联律间期、代偿间期及左房内径（LAD）、左心室舒张末期内径（LVEDD）、左室射血分数（LVEF）之间的相关性。方法：选择79例慢性心力衰竭患者作为CHF组,51例非心脏病患者作为对照组,所有研究对象均经超声心动图测量LAD、LVEDD、LVEF值,同时行动态心电图检查,计算HRT的3个指标：TO、TS、TT,及室性早搏前心率、联律间期、代偿间期。比较CHF组与对照组各指标的差异,并分析HRT各指标与其他指标的相关性。结果：CHF组TT、TO、LAD、LVEDD显著高于对照组,TS、LVEF显著低于对照组。CHF组TO与TS呈负相关（P=0.028）,与LVEF呈负相关（P=0.023）,TS与室性早搏前心率呈负相关（P=0.002）,与室性早搏联律间期（P=0.008）及代偿间期呈正相关（P=0.024）;对照组TO与年龄呈正相关（P=0.009）,与联律间期呈正相关（P=0.049）,TS与室性早搏前心率呈负相关（P=0.006）,与代偿间期呈正相关（P=0.014）;2组TT与其他所有指标间均无显著相关（P〉0.05）。结论：CHF患者HRT明显减弱,其中TT值增大提示患者室性早搏后窦性心率减速现象出现时间延迟,TT有望成为更客观的预测指标。     

Changes in Heart Rate, Heart Rate Variability, and Heart Rate Turbulence during Evolving Reperfused Myocardial Infarction

Depressed cardiac parasympathetic activity is associated with electrical instability and adverse outcomes after myocardial infarction (MI). Heart rate turbulence (HRT), reflecting reflex vagal activity, and heart rate variability (HRV), reflecting tonic autonomic variations are both reduced in the subacute phase of MI. However, the evolution of these components of cardiac autonomic control between subacute and chronic phase of MI has not been defined. We prospectively studied 100 consecutive patients with a recent first MI with ST-segment elevation, who underwent successful direct percutaneous coronary interventions. Beta-adrenergic blockers and angiotensin-converting enzyme (ACE) inhibitors were administered according to the state-of-the-art medical practice guidelines. HRT and HRV were measured from 24-hour ambulatory electrocardiographic recordings 10 days and 12 months after the index MI. There was no significant difference in mean RR interval between the subacute and chronic phase of MI (875 ± 145 versus 859 ± 122 ms). Indices of HRV increased significantly during the observation period (SDNN: from 88.8 ± 26.8 to 116.0 ± 35.7 ms, P < 0.001; SDNNi: from 37.9 ± 15.9 to 46.0 ± 16.3 ms, P < 0.001; SDANN: from 79.6 ± 34.7 to 105.6 ± 35.4 ms, P < 0.001). In contrast, there were no significant changes in indices of HRT (turbulence onset: from −0.008 ± 0.022 to −0.012 ± 0.025%; turbulence slope: from 7.78 ± 5.9 to 8.06 ± 6.8 ms/beat). In contrast to reflex autonomic activity, there was a significant recovery of tonic autonomic activity within 12 months after MI. These different patterns of recovery of reflex versus tonic cardiac autonomic control after MI need to be considered when risk stratifying post-MI patients.     

Heart Rate Turbulence after Ventricular Pacing Trains During Programmed Ventricular Stimulation

Background: This study tested the hypothesis that heart rate turbulence (HRT) following ventricular pacing trains depends on train cycle length, presence of retrograde ventriculoatrial (VA) conduction, and left ventricular (LV) function.
Methods: We analyzed digital recordings of programmed ventricular stimulation (PVS) performed in 82 patients (57 men) referred for electrophysiologic studies of ventricular arrhythmias, whose mean age was 64 ± 12 years and LV ejection fraction (EF) was 47 ± 15%. Profiles of sinus RR intervals after all available 8-beat ventricular pacing trains (600-and 400-ms) were averaged. Heart rate turbulence slope (HRTS) was analyzed as the maximum positive slope of a regression line through a sequence of 2–5 (HRTS2 - HRTS5) consecutive RR intervals within the first 5 RR intervals after the pacing train.
Results: Dynamics of RR intervals had biphasic and monophasic patterns, in patients with and without VA conduction, respectively. Sinus nodal response was less prominent after 600-ms than 400-ms pacing trains. After 400-ms pacing trains, HRTS was significantly shallower in patients with LVEF ≤40% than in those with LVEF >40%. HRTS4 was the best discriminator between the two groups (6.8 ± 8.6 ms/RR vs 19.6 ± 26.0 ms/RR, P = 0.017).
Conclusion: In patients with VA conduction, HRT after ventricular pacing trains reflects a combination of vagal withdrawal due to transient hypotension and suppression of sinus node automaticity. Attenuation of vagal modulation was detected in patients with LV dysfunction during standard PVS.     

Impact of Age and Basic Heart Rate on Heart Rate Turbulence in Healthy Persons

Postextrasystolic acceleration of heart rate (HR), known as HR turbulence (HRT) is attenuated in patients with coronary artery disease at increased risk of adverse events. The influence of age and basic HR on HRT have not been evaluated in a large cohort of persons. In 95 healthy individuals, HRT onset (TO) and slope (TS) were calculated from 24-hour ambulatory electrocardiograms, as well as the turbulence timing (TT). Gender specific differences in TO and TS were compared in simple, linear, weighted regression model. The influence of age and the basic HR preceding ventricular premature contractions on HRT were examined. We found that, in men and women, TO decreases as basic HR increases (P < 0.01). In contrast, in men, TS decreased as basic HR increases, whereas in women, basic HR influenced TS only slightly (P < 0.01). A multiple, linear regression model revealed a decrease in HRT with increasing age in men. In conclusion, physiological acceleration of the HR within the first 11 beats after premature ventricular complex (VPC) was observed in >75% of healthy individuals. An accelerating HR preceding the VPC influenced HRT in men. An increasing age was associated with a decrease in HRT in men and a decrease in TO in women. These results illustrate the importance of physiological modulations of HRT when used for risk stratification, especially in older populations.     

Variable Effects of Physical Training of Heart Rate Variability, Heart Rate Recovery, and Heart Rate Turbulence in Chronic Heart Failure

Background: Heart rate variability (HRV), heart rate turbulence (HRT), and heart rate recovery (HRR), indices that reflect autonomic nervous system (ANS) activity, are outcome predictors in patients with chronic heart failure (CHF). It is not clear, however, whether they reflect the same components of ANS activity. No study has examined the effects of physical training (PT) training on HRV, HRT, and HRR in CHF.
Study Objective: To examine the responses of HRV, HRT, and HRR to a PT program in patients presenting with CHF.
Methods: In 41 patients (mean age = 58.7 ± 10.2 years) in New York Heart Association CHF functional classes II or III, and with a left ventricular ejection fraction <40%, HRV, HRT, and HRR were measured before and after 8 weeks of PT.
Results: The training was clinically effective in all patients. Before versus after PT, standard deviation of all normal RR intervals increased from 107 ± 30 to 114 ± 32 ms (P = 0.047), high frequency increased from 210 ± 227 to 414 ± 586 ms²/Hz (P = 0.02), and the low/high frequency ratio decreased from 1.8 ± 1.55 to 1.1 ± 1.2 (P = 0.002). HRT and HRR did not change significantly after PT.
Conclusions: In patients with CHF, the positive effects of PT were limited to HRV indices, which reflect parasympathetic activity, without significantly changing HRR and HRT. These observations indicate that different mechanisms modulate HRV, HRR, and HRT, which provide complementary information regarding ANS activity. The 8-week PT program failed to completely normalize ANS function.     

Paradoxical Autonomic Modulation of Atrioventricular Nodal Conduction During Heart Rate Turbulence

WICHTERLE, D., et al .: Paradoxical Autonomic Modulation of Atrioventricular Nodal Conduction During Heart Rate Turbulence. Heart rate turbulence (HRT) represents a biphasic chronotropic response of sinus rhythm to a single ventricular premature beat (VPB). It consists of early acceleration and late deceleration of heart rate and is predominantly mediated by the autonomic nervous system. The aim of this study was to investigate if autonomic perturbations after a VPB exert a significant effect on AV conduction. Both surface ECG and the high right atrial electrogram were recorded at a sampling frequency of 1000 Hz in 26 patients (24 men, mean age 49 ± 12 years) referred for electrophysiological evaluation. The stimulation protocol consisted of series of single ventricular extrastimuli delivered from the right ventricular apex at decreasing coupling intervals. A biphasic profile of AV intervals after a single VPB was observed. The response of AV conduction to a VPB was approximately 25 times and 15 times weaker in the early and late phase, respectively, than that of R-R intervals. Thus, AV interval dynamics significantly preceded the change in R-R intervals, which is in conflict with the near to zero phase of transfer function between R-R and AV intervals described in previous studies. A significant AV turbulence was observed consisting of early shortening and later prolongation of AV intervals after VPB. Its magnitude was much smaller than that of HRT. Dynamics of AV delay has little impact on the accuracy of HRT assessment from surface ECG. The significant temporal dissociation of R-R and AV interval dynamics after a VPB remains unexplained. (PACE 2003; 26[Pt. II]:440–443)