冠心病患者心率震荡与静息心率的相关性研究

目的研究心率震荡（HRT）和静息心率（RHR）、心率变异性时阈指标（SDNN）在冠心病（CHD）中的变化，以及它们之间的关系。方法选择有室性早搏的冠心病患者53例，根据24h动态心电图（Hoher）记录资料分组，A组（良性室性心律失常组：偶发室早）32例，B组（不良室性心律失常组：伴有阵发性室性心动过速或多源性室早或频发室早）21例，动态心电图记录SDNN和6am的静息心率（RHR），计算心率震荡的两个参数：震荡初始（TO）和震荡斜率（1S），比较两组间的差别，分析TO、TS与SDNN、RHR之间的相关性。结果B组TO值高于A组（0、80％±3．94％vs-1．45％±4．37％，p〈0．05），而TS值低于A组（11．03±11．01ms／RR间期vs19．77±19．00ms／RR间期，p〈0．05），RHR值明显高于A组（82．18±9．70bpmvs70．94±11．32bpm，p〈0．01），B组TO与SDNN呈负相关，与静息心率呈正相关；TS与静息心率呈负相关，而与SDNN无明显相关。结论冠心病患者伴有不良室性心律失常时，心率震荡现象减弱，心率震荡增加，提示心脏自主神经平衡的破坏与不良性室性心律失常有一定的内在联系。     

静息心率与心血管疾病的研究进展

静息心率与心血管疾病的关系,近年来日益受到人们的重视。随着研究的不断进展,静息心率被作为心血管疾病的危险因素逐步被人们所接受。同时,也有学者发现静息心率是心血管疾病患者死亡的预测因子,这使静息心率逐步成为人们的研究热点。现综述了静息心率与心血管疾病目前的研究进展,并初步提出了心血管疾病患者使用β受体阻滞剂与以往不同的保护机制。     

静息心率与心血管疾病关系研究进展

静息心率可以反映交感神经和副交感神经兴奋变化,静息心率对心血管疾病的发生和影响已在相关的病理生理学研究中得到证实。心力衰竭、冠心病、高血压、心房颤动、缺血性卒中等心血管疾病的发生、发展以及预后均与静息心率有一定的相关性。有效干预静息心率,对进一步降低与其相关疾病的患病率及改善患者预后具有十分重要的意义。     

对静息心率增快与冠状动脉疾病关系的再认识

静息心率测量是既基本又简单的物理检查手段。众多的前瞻性流行病学研究证实静息心率与冠状动脉疾病的发病率和死亡率相关。现就静息心率增快与冠状动脉粥样硬化性心脏病的相关性及有效控制静息心率在冠状动脉疾病的防治作用做一综述。     

心率震荡现象

心血管疾病患者有发生猝死的潜在危险性。寻求有效的高危预测指标为患者进行危险分层和预后判断，对延长患者的生存时间有重要的意义。目前认为，猝死的发生是心脏器质性病变、自主神经对心脏调节失衡及病变心肌易颤阈值降低相互影响所致的结果。通过超声心动描记术等检查可以了解心脏     

有关控制心率重要性的探讨

流行病学研究表明：快速的静息心率与心血管病的发病率、心血管病及其他原因所致的死亡有关。心率增快是死亡、特别是心血管病所致死亡的独立危险因子。本文对有关控制心率的重要性作一探讨。     

慢性心力衰竭患者动态心率震荡分析

目的：探讨窦性心率震荡（HRT）的新测量指标动态心率震荡（TD）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,分析其与传统高危预测指标的相关性及预测CHF患者价值。方法纳入2011年9月~2013年6月在天津市胸科医院就诊的CHF患者120例作为CHF组,同期纳入非器质性心脏病患者30例作为对照组,将CHF组按NYHA分级分为轻度CHF组（心功能Ⅰ~Ⅱ级,n=72）和中重度CHF组（心功能Ⅲ~Ⅳ级,n=48）。所有患者行放射免疫法检测B型脑钠肽（BNP）水平,超声心动图检查左房内径（LAD）、左室舒张末径（LVEDD）、左室射血分数（LVEF）;24 h动态心电图检查记录心率变异性时域（SDNN）、平均心率、室性早搏前心率（HRVPC）以及RR间期,计算HRT指标（包括TO、TS和TD）。比较各组之间的差异,分析HRT各指标与年龄、性别、LAD、LVEDD、LVEF、BNP的相关性。结果与对照组相比,CHF组SDNN缩短[（95.67±30.22） msvs.（131.65±20.71）ms],TO和TD更高[TO：（-1.50±2.71）%vs.（0.61±1.95）%;TD：（0.012±0.004）mm/RRIvs.（0.063±0.031）mm/RRI],LAD和LVEDD更高[LAD：（36.11±2.24）mmvs.（47.65±2.13）mm;LVEDD：（43.65±7.33）mmvs.（62.13±8.70）mm],BNP明显升高[（80.05±32.30）pg/ml vs.（941.00±139.17）pg/ml],TS和LVEF更低[TS：（12.13±3.67）vs.（6.80±5.33）;LVEF：（67.30±5.21）% vs.（38.22±12.75）%],而且随着CHF程度的加重,上述改变更加明显。CHF组TO与TS、LVEF、SDNN负相关（P＜0.05）;TS与SDNN正相关（P＜0.05）,与HRVPC、BNP负相关（P＜0.05）。结论 CHF患者HRT明显减弱,其中TO和TS均受到SDNN的影响,而TD与HRVPC、SDNN、LVEF、BNP指标无关。     

静息心率控制对冠心病病死率及并发症的影响

目的 探讨静息心率(RHR)的控制与冠心病病死率及并发症的关系.方法 106例冠心病患者按RHR水平分为三组:50～65次/min组(A组)36例,66～79次/min组(B组)35例,≥80次/min组(C组)35例,对心绞痛、心律失常、心力衰竭、猝死发生率进行统计分析.结果 三组症状发生率分别为30.5%、48.5...     

单纯收缩期高血压患者的心率震荡与心率变异

目的:观察单纯收缩期高血压(ISH)患者的心率震荡(HRT)和心率变异(HRV)的变化。方法:记录24h动态心电图,计算窦性HRT的初始值(TO)和震荡斜率值(TS)以及HRV的SDNN、pNN50和LF/HF,比较ISH组(85例)、普通高血压组(80例),正常对照组(58例)3组之间的差别,分析HRT和HRV之间的相关性。结果:ISH组、普通高血压组的HRT和HRV与正常对照组的HRT和HRV比较差异均有统计学意义(P<0.05),ISH组的TS和LF/HF较普通高血压组明显降低(P<0.05);HRV的各项指标和HRT均有良好的相关性,其中pNN50与HRT相关系数最高。结论:原发性高血压患者有显著的HRT减弱及HRV的异常,其中ISH患者较普通高血压患者更加明显,且HRT与HRV的密切相关,表明心脏自主神经功能紊乱可能对于高血压的发生及预后均有重要影响。     

原发性高血压前期患者窦性心率震荡现象及其临床意义

目的探讨原发性高血压前期患者窦性心率震荡(heart rate turbulence,HRT)现象的特征及其临床意义。方法选择45例原发性高血压前期患者(高血压前期组)及39名健康志愿者(对照组)进行24 h动态心电图检查,离线分别计算震荡初始(TO)值及震荡斜率(TS)值。结果两组基线资料比较,差异无统计学意义(P>0.05)。高血压前期组震荡初始值较对照组明显升高[(1.23±0.70)%vs.(-0.60±0.56)%,P<0.05],震荡斜率值明显降低[(3.23±1.12)ms/RR vs.(5.69±0.93)ms/RR,P<0.05],差异均有统计学意义。结论原发性高血压前期患者存在室性期前收缩后窦性HRT减弱现象。     

Influence of Heavy Cigarette Smoking on Heart Rate Variability and Heart Rate Turbulence Parameters

Background: Cigarette smoking increases the risk of cardiovascular events related with several mechanisms. The most suggested mechanism is increased activity of sympathetic nervous system. Heart rate variability (HRV) and heart rate turbulence (HRT) has been shown to be independent and powerful predictors of mortality in a specific group of cardiac patients. The goal of this study was to assess the effect of heavy cigarette smoking on cardiac autonomic function using HRV and HRT analyses. Methods: Heavy cigarette smoking was defined as more than 20 cigarettes smoked per day. Heavy cigarette smokers, 69 subjects and nonsmokers 74 subjects (control group) were enrolled in this study. HRV and HRT analyses [turbulence onset (TO) and turbulence slope (TS)] were assessed from 24‐hour Holter recordings. Results: The values of TO were significantly higher in heavy cigarette smokers than control group (?1.150 ± 4.007 vs ?2.454 ± 2.796, P = 0.025, respectively), but values of TS were not statistically different between two groups (10.352 ± 7.670 vs 9.613 ± 7.245, P = 0.555, respectively). Also, the number of patients who had abnormal TO was significantly higher in heavy cigarette smokers than control group (23 vs 10, P = 0.006). TO was correlated with the number of cigarettes smoked per day (r = 0.235, P = 0.004). While LF and LF/HF ratio were significantly higher, standard deviation of all NN intervals (SDNN), standard deviation of the 5‐minute mean RR intervals (SDANN), root mean square of successive differences (RMSSD), and high‐frequency (HF) values were significantly lower in heavy smokers. While, there was significant correlation between TO and SDNN, SDANN, RMSSD, LF, and high frequency (HF), only HF was correlated with TS. Conclusion: Heavy cigarette smoking has negative effect on autonomic function. HRT is an appropriate noninvasive method to evaluate the effect of cigarette on autonomic function. Simultaneous abnormal HRT and HRV values may explain increased cardiovascular event risk in heavy cigarette smokers.     

Effects of Postectopic Heart Rate Turbulence on Measures of Heart Rate Variability in Patients after an Acute Myocardial Infarction

Background: Heart rate (HR) turbulence lasting up to 15 beats after ventricular premature beats (VPBs) may have profound effects on HR variability measures. Aim of this study was to examine the effects of HR turbulence on HR variability measures. Methods: We developed an algorithm, which deletes 15 consecutive RR intervals after VPBs and examined the effects of the HR turbulence removal on the HR variability measures in patients after an acute myocardial infarction (AMI). Two hundred and sixty seven patients with left ventricular ejection fraction (LVEF) ≤ 0.40 and occurrence of VPBs were included in the study. Differences (%) between original HR data and HR turbulence edited data were compared. Results: HR turbulence editing had variable effects on different HR variability indexes. Ultra low (ULF) and very low frequency (VLF) spectral components were mostly affected by the HR turbulence removal. Both ULF and VLF decreased significantly both at baseline Holter recordings (ULF: P = 0.006, VLF: P = 0.031) and at 6 weeks from AMI (ULF: P < 0.001, VLF: P = 0.001). The number of VPBs had a marked influence on results, e.g., when the number of VPBs exceeded the highest decile (≈50 VPBs/hour), the ULF and VLF spectral component were >30% lower after removal of turbulence. In addition, the prediction of arrhythmic events by ULF component improved after turbulence removal (AUC: 0.69 ‐>0.74). Conclusions: HR turbulence affects HR variability measures, especially the ULF and VFL spectral components. Editing of the HR turbulence should be considered when HR variability is measured from Holter recordings. Ann Noninvasive Electrocardiol 2011;16(2):123–130     

Clinical Covariates of Abnormal Heart Rate Turbulence in Coronary Patients

Background: The aim of this study is to evaluate the association between heart rate turbulence (HRT) parameters and clinical characteristics of coronary artery disease (CAD) patients. Methods and Results: In 122 patients (mean age 62 ± 9 years) with angiographically documented CAD, 24‐hour Holter monitoring with HRT analysis was performed to evaluate turbulence onset (TO) and turbulence slope (TS). There was a significant correlation between TO and TS (P =?0.31; P < 0.001) . According to quartile values, TO ≥?0.37% and TS ≤ 4.25 ms/RR were considered as abnormal in this patient population. Average values of TO were higher and TS lower in patients over 60 years, in patients with a past history of myocardial infarction and in those with EF < 40%. Considering pharmacotheraphy, higher (better) values of TS were observed in patients on statins, nitrates, and beta‐blockers while lower TS values were noted in patients on calcium blockers. Patients with abnormal parameters of HRT compared to group with normal HRT values were characterized by features of more advanced CAD: age over 60 years (75% vs 49%), past history of MI (75% vs 64%), and EF < 40% (25% vs 3%). Multivariate analysis revealed age > 60 years (OR 1.27; P = 0.002) and EF < 40% (OR 1.39; P = 0.001) as independent clinical factors associated with abnormal HRT parameters. Conclusions: HRT parameters are influenced by clinical characteristics and pharmacotherapy of studied patients with TS more than abnormal TO depending on clinical characteristics of patients. Advanced age, prior myocardial infarction and left ventricular dysfunction are key factors influencing values of HRT parameters.     

心肌梗死患者搭桥术后窦性心率震荡的临床研究

目的通过对心肌梗死患者冠脉搭桥术后进行窦性心率震荡(HRT)的检测及结果分析,评价HRT对心梗患者冠脉搭桥术后死亡率的预测价值。方法40例心梗患者搭桥术后和23例正常人分为心梗组和对照组;其中心梗组按检测结果再分为:震荡初始(TO)、震荡斜率(TS)2项阳性组、TO或TS1项阳性组和阴性组。选用美高仪公司生产的带有HRT检测功能的数字动态心电记录器,对入组病例行24h动态心电图检查,并用Holter12TopVersion分析软件分析单次室早后窦性心率震荡值TO及TS。随后进行平均6个月的随访。结果①心梗组TO、TS的阳性检测率均高于对照组,(分别为p<0.01和p<0.05);②平均6个月随访结果:心梗组中2项阳性组的3例患者猝死,1项阳性组和阴性组无死亡病例。结论室早后窦性心率震荡是一种对心梗患者冠脉搭桥术后新的有效的猝死高危预测指标。     

窦性心率震荡预测心肌梗死后心衰

目的本研究目的在于探讨性窦心率震荡（HRT）预测陈旧性心肌梗死（OMI）后发生心力衰竭的价值。方法对192例有完整资料的OMI患者进行回顾性分析,将其分为：A组（合并心力衰竭）和B组（无心力衰竭）,选择年龄、性别相匹配的无心肌梗死病史的90例患者作对照组。根据动态心电图结果分析HRT指标震荡初始（TO）、震荡斜率（TS）和静息心率（RHR）、正常心动周期标准差（SDNN）。利用超声心动图对OMI患者进行心功能评价,测量左室射血分数（LVEF）和左室舒张末期内径（LVEDD）。分析HRT指标和SDNN、RHR、LVEF、LVEDD的相关性。结果 ①A组TO和TS与B组及对照组比较,均有统计学差异（p〈0.05）,B组TO和TS均在正常范围内,但与正常对照组比较仍有统计学差异;②A组LVEF、LVEDD、SDNN、RHR均与B组及对照组具有显著的统计学差异（p〈0.05）;③相关性分析显示TO与SDNN呈负相关,但TO和其他因素无明显相关性,TS与SDNN和LVEF呈正相关,而与LVEDD和RHR呈负相关。结论 HRT尤其是量化的TS能更好地预测OMI患者合并心力衰竭的风险,对于降低梗死后心力衰竭的发生率、改善预后和降低死亡率具有重要的临床应用价值。     

心律震荡

急性心肌梗死患者是心源性猝死的高危人群 ,寻找猝死高危人群的预测指标一直是心血管领域备受重视的课题。最近 ,国外学者研究了一个新的心电生理预测指标———心律震荡 ,认为这是一个独立于现有预测指标的新指标 ,其灵敏度和特异度都很高。本文就心律震荡这一新指标作一综述。     

Heart Rate Turbulence for Prediction of Heart Transplantation and Mortality in Chronic Heart Failure

Background: Previous studies have shown conflicting results about the value of heart rate turbulence (HRT) for risk stratification of patients (pts) with chronic heart failure (CHF). We prospectively evaluated the relation between HRT and progression toward end‐stage heart failure or all‐cause mortality in patients with CHF. Methods: HRT was assessed from 24‐hour Holter recordings in 110 pts with CHF (54 in NYHA class II, 56 in class III–IV; left ventricular ejection fraction (LVEF) 30%± 10%) on optimal pharmacotherapy and quantified as turbulence onset (TO,%), turbulence slope (TS, ms/RR interval), and turbulence timing (beginning of RR sequence for calculation of TS, TT). TO ≥ 0%, TS ≤ 2.5 ms/RR, and TT >10 were considered abnormal. End point was development of end‐stage CHF requiring heart transplantation (OHT) or all‐cause mortality. Results: During a follow‐up of 5.8 ± 1.3 years, 24 pts died and 10 required OHT. TO, TS, TT, and both (TO and TS) were abnormal in 35%, 50%, 30%, and 25% of all patients, respectively. Patients with at least one relatively preserved HRT parameter (TO, TS, or TT) (n = 98) had 5‐year event‐free rate of 83% compared to 33% of those in whom all three parameters were abnormal (n = 12). In multivariate Cox regression analysis, the most powerful predictor of end point events was heart rate variability (SDNN < 70 ms, hazard ratio (HR) 9.41, P < 0.001), followed by LVEF ≤ 35% (HR 6.23), TT ≥ 10 (HR 3.14), and TO ≥ 0 (HR 2.54, P < 0.05). Conclusion : In patients with CHF on optimal pharmacotherapy, HRT can help to predict those at risk for progression toward OHT or death of all causes. Ann Noninvasive Electrocardiol 2010;15(3):230–237