Twenty-Four Hour Time Domain Heart Rate Variability and Heart Rate: Relations to Age and Gender Over Nine Decades

Objectives. This study sought to define the effects of age and gender effects on the normal range of time domain heart rate variability (HRV) over nine decades in healthy subjects.Background. Low HRV is considered an independent marker of mortality risk. However, the age-related decline in HRV may limit its predictive value, particularly in the elderly. Delineation of the range of HRV in healthy subjects over the life span is needed. Gender-related differences in HRV also need clarification.Methods. We determined, according to decade, 24-h heart rate (HR) and HRV of 260 healthy subjects (10 to 99 years old; 112 male, 148 female) by means of five standard time domain measures: standard deviation of all normal sinus RR intervals over 24 h (SDNN), standard deviation of the averaged normal sinus RR intervals for all 5-mm segments (SDANN), mean of the standard deviations of all normal sinus RR intervals for all 5-min segments (SDNN index), root-mean-square of successive normal sinus RR interval difference (rMSSD) and the percentage of successive normal sinus RR intervals >50 ms (pNN50).Results. 1) HRV decreased with aging, the pattern of change being measure dependent. HRV (SDNN and SDANN) decreased only very gradually, reaching 60% of baseline (second-decade values) by the tenth decade. With the SDNN index, HRV decreased linearly with aging, reaching 46% of baseline by the tenth decade. Using pNN50 and rMSSD, HRV decreased most rapidly, reaching 24% and 47% of baseline, respectively, by the sixth decade and then stabilized. 2) Using the SDNN index, rMSSD and pNN50, HRV of subjects >65 years old fell below published cutpoints for increased risk of mortality in 25%, 12% and 4%, respectively. 3) At age <30 years, HRV for all measures was lower in female than male subjects. Gender differences decreased at age >30 years and disappeared at age >50 years. 4) HR also declined with aging but much more slowly. HR at age <50 years was faster in female than in male subjects. Gender differences disappeared thereafter.Conclusions. 1) Using all measures, HRV of healthy subjects declines with aging, with measure-dependent patterns. 2) Using the SDNN index, rMSSD and pNN50, HRV of healthy subjects, particularly those >65 years old, may decrease to below levels associated with increased risk of mortality. 3) Gender influences HRV. Gender differences in HRV are age and measure dependent. 4) Age and gender also affect heart rate.     

Sex Steroids and Heart Rate Variability in Patients after Myocardial Infarction

Background: Although the relationship between sex steroid levels and coronary artery disease (CAD) has been the subject of many studies there are still controversies concerning the role of sex steroids in CAD. In patients with CAD, especially after a myocardial infarction, there is evidence for autonomic nervous system dysfunction. However, there is no data detailing the relationship between sex steroids and cicardian autonomic activity in patients with CAD. The aim of the study was to evaluate the association between sex steroids and heart rate variability (HRV) parameters in postinfarction patients. Methods: In 88 postinfarction men (aged 36–73, average 53 years), 24‐hour Holter monitoring was performed to assess HRV parameters: SDNN, SDNNI, SDANN, rMSSD, pNN50, and levels of the following hormones were measured: testosterone, estradiol, free testosterone index, and estradiol/testosterone ratio. Univariate and multivariate regression analyses were used to investigate the relationship between HRV parameters and levels of tested hormones. Results: Increased testosterone levels were associated with increased SDNN (r = 0.38, P = 0.03), increased rMSSD (r = 0.51, P = 0.002), and increased pNN50 (r = 0.45, P = 0.007). These associations remained significance after adjustment for age, ejection fraction, and other relevant clinical covariates. There was no significant association between estradiol and HRV parameters. Conclusion: In men with a history of myocardial infarction, higher levels of testosterone are associated with higher HRV measures of parasympathetic activity. These findings suggest that testosterone beneficially influences autonomic regulation of the heart.     

Predictive value of heart rate variability for the recurrence of chronic atrial fibrillation after electrical cardioversion

BACKGROUND: The relation between heart rate variability (HRV) and occurrence of atrial fibrillation (AF) in paroxysmal AF has been well studied, but there are controversial observations regarding the relation of HRV parameters to the recurrence of chronic AF after cardioversion. HYPOTHESIS: The present study compared HRV parameters of patients with chronic AF on the second day of cardioversion with a healthy control group and investigated their predictive value for AF recurrence. METHODS: Forty-one patients with chronic AF (> 3 months), who had various underlying cardiovascular disorders, were enrolled to the study. Of these, 31 patients were successfully cardioverted by external direct current shock, but 27 patients fulfilled the entry criteria. Twenty healthy subjects served as a control group. On the second day of restoration of sinus rhythm, 24-h Holter recording was obtained and the following time-domain indices of HRV were measured: SDNN (the standard deviation of the mean RR interval expressed in ms), SDANN (the SD of the averages of RR intervals in all 5-min segments of the 24-h recording), rMSSD (the root mean square of differences of successive RR intervals), and pNN50 (the percentage of adjacent RR intervals that differed by more than 50 ms). Patients were followed-up for 6 weeks for recurrence of AF. RESULTS: After cardioversion, SDNN and SDANN were found to be significantly lower in the AF group than in the control group (86.4 +/- 31.7 ms vs. 142.1 +/- 40.2 ms, and 57 +/- 17.4 ms vs. 124.4 +/- 37.7 ms, p < 0.001 and p < 0.001, respectively). The indices of vagal modulation of heart rate (rMSS and pNN50) were not different between the AF group and the control group. Recurrence of AF was observed in 15 patients. In these patients, all HRV parameters were significantly depressed compared with those with maintained sinus rhythm. Logistic regression analysis revealed that only decreased pNN50 was an independent predictor of AF relapse (relative risk = 1.5, p = 0.02, 95% confidence interval 1.1-2.2). There was also a trend toward a shortened SDNN as a predictor of AF recurrences. CONCLUSION: Suppressed HRV parameters and decreased vagal tone are probably a risk factor for AF recurrences after cardioversion to sinus rhythm in a specific subset of patients with chronic AF.     

750例健康儿童心率变异性分析

目的对750例健康儿童心率变异性（heart rate variability,HRV）进行分析,观察正常值范围及HRV与年龄的关系。方法对750例来我院体格检查的正常健康儿童分为以下6个年龄组：新生儿组（〈1个月）、婴儿组（1个月一1岁）、幼儿组（1～3岁）、学龄前组（3～6岁）、学龄组（6—11岁）和青春期组（11—16岁）,进行24h动态心电图检测,分析HRV时域（SDNN、SDANN、PNNSO、rMSSD）及频域（TF、VLF、LF、HF、LF／HF）结果。结果（1）各年龄组HRV时域分析SDNN、SDANN、rMSSD差异有统计学意义（P〈0．05或P〈0．01）,随年龄增长,HRV有增大趋势。（2）HRV频域分析TF、VLF、LF、HF差异有统计学意义（P〈0．01）,数值随年龄增大而增大。结论不同年龄段HRV时域及频域结果不同,HRV随年龄增加而增大,可对临床研究异常HRV提供参考依据。     

原发性高血压心率变异性测定的意义

目的：探讨原发性高血压患不同时期心率变异性的改变。方法：记录原发性高血压病人46例,对照组23例的24小时动态心电图,进行心率变异性的时域分析。结果：（1）原发性高血压组时域分析的各项参数指标除PNN50外,SDNN、SDANN、SDANNindex,rMSSD显减低（P＜0．01）;（2）随高血压病程进展（1、2、3级）SDNN、SDANN、SDANNindex逐渐降低,各项之间均存在极显的差异。结论：原发性高血压患的HRV显减低,且随病程进展,变化愈显,提示HRV分析对高血压患有分层及预后的价值。     

高血压患者心率减速力与室性心律失常

目的研究高血压患者的心率减速力,并分析其与室性心律失常的相关性。方法筛选无糖尿病和其他致自主神经功能损伤疾病的原发性高血压患者180例,以及同期健康体检者60例作为对照组,进行24h动态心电图检查,离线计算DC值、HRV时域指标,最后进行高血压与健康对照人群的对比分析,以及高血压患者的DC值和HRV时域指标与VA的相关性分析。结果高血压患者VA各组的DC值以及HRV时域指标的SDNN、SDANN、rMSSD、PNN50较对照组均显著降低（p〈0.05）,且高血压患者的DC、SDNN和SDANN与VA程度呈负相关（p〈0.05）。结论高血压患者的DC值及HRV明显降低,且DC、SDNN、SDANN和PNN50与高血压患者VA程度呈负相关。早期对自主神经功能紊乱进行干预治疗,可能有利于减少高血压患者VA的发生。     

Effect of aprindine on heart rate variability indices in patients with ischemic heart disease

BACKGROUND: Decreased heart rate variability indices (HRV) are associated with untoward outcome of patients with ischemic heart disease (IHD). Most class I antiarrhythmic agents decrease HRV, but aprindine (a new class I antiarrhythmic agent) is reported to increase HRV in patients without ischemia. HYPOTHESIS: The study was undertaken to determine whether apridine might increase HRV in patients with IHD. METHODS: To investigate the effect of aprindine on HRV in patients with IHD, we performed 24-h ambulatory electrocardiogram (ECG) at the end of placebo and aprindine (60 mg daily) treatment phases on 38 patients with IHD and at least isolated premature ventricular contractions (PVC). The study protocol utilized a single blind, 4-week, placebo-controlled design. Heart rate variability from ambulatory ECG included SDNN (ms), SDANN (ms), SD (ms), rMSSD (ms), pNN50 (%); frequency analysis of HRV consisting of total (ms, 0.01-1.00 Hz), low (ms, 0.04-0.15 Hz), and high (ms, 0.15-0.40 Hz) components. RESULTS: Study patients were divided into three groups according to the severity of IHD and antiarrhythmic efficacy of aprindine. Group 1 consisted of 15 patients with angina with single-vessel disease, and Group 2 was composed of 10 patients with either multivessel disease or post myocardial infarction; PVCs decreased in both groups as result of aprindine treatment. Group 3 consisted of 13 patients who showed no decreased PVC after aprindine treatment. RMSSD increased, and pNN50 and high-frequency spectra tended to increase in Group 1, while SD, rMSSD, pNN50, and total and low-frequency spectra decreased in Group 3; no significant changes were observed in Group 2. Aprindine significantly augments vagal activity, as reflected by the increase of rMSSD, pNN50, and high-frequency spectra in mild IHD. CONCLUSION: These salutary effects are less in more severe IHD, but aprindine does not aggravate HRV. Thus, if there are salutary effects on arrhythmias and no proarrhythmic effects, aprindine could be prescribed to patients with IHD without concern about decreasing HRV.     

比索洛尔对糖尿病自主神经病变患者心率变异性的影响

目的：通过比较糖尿病自主神经病变者服用比索洛尔（康可）前、后心率变异（HRV）的变化，以了解比索洛尔对HRV的影响。方法？用动态心电图测定50例糖尿病自主神经病变的病人在比索洛尔治疗前、后的HRV时域各项指标，并与对照组50例进行比较。结果：与对照组比较，比索洛尔组的心率变异时域指标SDNN、rMSSD、pNN50均明显下降（P〈0．01）。治疗组比索洛尔治疗后SDNN、rMSSD、pNN50均较用药前显著升高（P〈0．01）。结论：糖尿病合并自主神经病变者HRV降低，比索洛尔能提高心率变异性，改善预后。     

Sex steroids and heart rate variability in men with coronary artery disease after myocardial infarction

The role of sex steroids in coronary artery disease (CAD) has been studied for years. In patients after myocardial infarction autonomic nervous system dysfunction has been described. Heart rate variability (HRV) analysis is one of the method of autonomic nervous system evaluation. The aim of the study was to evaluate correlations between sex steroids and HRV in 88 men (aged 36-73, av. 53 yrs), with the history of MI, with angiographically documented CAD. In all the patients 24-hour Holter monitoring was performed to assess HRV time domain parameters: SDNN, SDNNI, SDANN, rMSSD, pNN50. Levels of testosterone and estradiol were measured in two subsequent blood samples, taken with 30 min interval. Free testosterone index as well as estradiol/testosterone ratio were assessed. For statistics r-Spearman test was used. Positive correlations were found between testosterone and SDNN (r = 0.38, p = 0.03), testosterone and rMSSD (r = 0.51, p = 0.002) and between testosterone and pNN50 (r = 0.45, p = 0.007). Since rMSSD and pNN50 are parameters describing parasympathetic activity, our results suggest that in CAD men with the history of myocardial infarction, testosterone may influences the function of autonomic nervous system promoting parasympathetic dominance. It can be favorable for the circulatory system function.     

Heart rate variability in heart failure

BACKGROUND: Heart rate variability (HRV) depicts the functional status of the autonomic nervous system and its effects on sinus node. Recently, HRV analysis has been introduced in patients with heart failure (CHF) to identify those who are at risk of cardiac death. AIM: To analyse HRV in patients with CHF with depressed left ventricular ejection fraction (EF) and to relate HRV parameters to EF, NYHA functional class and other clinical parameters. METHODS: The study group consisted of 105 patients with CHF (88 males, 17 females, mean age 54+/-12 years); 77 patients had ischaemic cardiomyopathy, and 28 - dilated cardiomyopathy. All patients were in NYHA class II-IV and had EF <40%. The mean value of echocardiographically assessed EF was 26.9+/-8.3%. The control group consisted of 30 gender- and age-matched healthy subjects. HRV analysis was performed in the time-domain from 24-hour Holter ECG. RESULTS: All HRV variables were significantly lower in patients with CHF than in controls. Patients with NYHA class II had higher values of SDNN and SDANN than those in class III or IV. Patients with sustained or non-sustained ventricular tachycardia (VT) detected during Holter monitoring had lower SDNN and SDANN values than those without VT. Patients with diabetes had significantly lower SDNN and rMSSD values than the patients without diabetes. Similar results were found when patients with or without hypertension were compared. HRV parameters were similar in patients either with ischaemic or dilated cardiomyopathy. Also the values of EF were similar (27.4+/-8.4 vs 25.0+/-8.3%, respectively, NS). In the whole group of patients with CHF the values of SDNN and SDANN significantly correlated with EF (SDNN p<0.001, r=0.42; SDANN p<0.001, r=0.51). This correlation was stronger in the subset of patients with ischaemic cardiomyopathy (SDNN p=0.002. r=0.54; SDANN p=0.002; r=0.53) than in those with dilated cardiomyopathy (SDNN p=0.012, r=0.23; SDANN p=0.008, r=0.42). A significant negative correlation was found between all HRV parameters and NYHA class (SDNN p<0.001, r = -0.33; SDANN p<0.001, r = -0.38; rMSSD p<0.001, r = -0.13). CONCLUSIONS: HRV is depressed in patients with CHF compared with healthy subjects. Among patients with CHF, HRV is further decreased in patients with more advanced NYHA class, lower EF and in those with diabetes, hypertension or VT on Holter monitoring.     

充血性心力衰竭心率变异性改变及其与心室重塑的关系

目的:检测充血性心力衰竭患者心率变异性(HRV)改变,探讨其与心室重塑的关系。方法:采用Holter检查系统检测了36例CHF患者HRV指标24h正常R-R间期标准差(SDNN)、24h内每5min平均正常R-R间期的标准差(SDANN)24h内每5min的正常R-R间期标准差的平均值(SDNNI),相邻正常R-R间期差值的均方根(rMSSD),相邻正常R-R间期差值≥50ms心搏数占总R-R间期数的百分数(PNN50)及超声心动图指标左心室舒张末期内径(LVEDD),收缩末期内径(LVESD),左心室后壁舒张末期厚度(LVPWT),心室间隔舒张末期厚度(IVST),左心室射血分数(LVEF),左心室舒张早期及舒张晚期充盈速度比值(E/A)及左心室重量指数(LVMI),并以20例健康体检者为对照。结果:CHF患者HRV各时域指标均下降,与对照组相比有显著差异(P<0.05～<0.01)。多元回归分析显示SDNN,SDNNI与LVEDD,LVPWT呈负相关(r=-0.337～-0.362,P<0.05);rMSSD,PNN50与LVEDD,LVESD呈负相关(r=-0.142～-0.433,P<0.05);rMSSD、PNN50与LVEF呈正相关(r=0.387～0.464,P<0.05～<0.001)。结论:CHF患者HRV下降,并与心室重塑有关。     

阻塞性睡眠呼吸暂停综合征心率变异性的变化及其意义

目的 :研究阻塞性睡眠呼吸暂停综合征 （OSAS）患者心率变异性 （HRV ）的变化。方法 :经夜间多导睡眠图（PSG） 7h监测及动态心电图检查 ,选取重度 OSAS患者及正常受试者各 2 0例 ,采用时域法和频域法分析 HRV。结果 :OSAS组与对照组比较时域指标 SDANN ,SDNN ,r MSSD显著增高 ,SDNN- index则显著降低 ,频域指标VL F,L F,HF,L Fnrom,HFnorm及 L F/HF均较对照组显著增高。结论 :OSAS患者交感神经及副交感神经活动均增强 ,交感神经活动增强占优势     

高原世居藏族健康成人心率及心率变异性分析

目的评价高原世居藏族健康成人心率及心率变异性时域指标的特点。方法对100例高原世居藏族健康成人,75例西宁地区藏族健康成人和100例西宁地区汉族健康成人进行全程24h动态心电图检查,分析心率指标(24h总心搏数、24h最小心率、24h最大心率和每分平均心率)和心率变异性(Heartratevariability,HRV)时域指标(SDNN、SDANN、SDNNindex、rMSSD和pNN50)。结果高原世居藏族健康成人心率指标:24h总心搏数、24h最大心率、每分平均心率均低于西宁地区藏、汉族健康成人。高原世居藏族健康成人的心率变异时域指标rMSSD、pNN50高于西宁地区藏、汉族健康成人。结论高原世居藏族健康成人心率偏慢,世居藏族迷走神经活性略高。     

Cardiac autonomic tone and its relation to nonsustained ventricular tachyarrhythmias in idiopathic dilated cardiomyopathy

BACKGROUND: In contrast to postinfarct patients, little is known about cardiac autonomic tone and its relation to spontaneous ventricular tachyarrhythmias in idiopathic dilated cardiomyopathy (IDC). Both heart rate variability (HRV) and baroreflex sensitivity (BRS) are indices of autonomic innervation of the heart. HYPOTHESIS: The aim of the present study was to determine the relation between cardiac autonomic tone assessed by HRV and BRS and spontaneous nonsustained ventricular tachycardia (NSVT) on Holter in a large patient population with IDC. METHODS: 24-h digital Holter recordings including HRV analysis and BRS testing were prospectively performed in 137 patients with IDC and preserved sinus rhythm. Mean age was 48 +/- 12 years, and mean left ventricular (LV) ejection fraction was 32 +/- 9%. The HRV analysis on Holter included the mean RR interval (RRm), the standard deviation of all normal RR intervals (SDNN), the square root of the mean of the squared differences between adjacent normal RR intervals (rMSSD), and the proportion of adjacent normal RR intervals differing more than 50 ms (pNN50). Testing for BRS was performed noninvasively using the phenylephrine method. RESULTS: Of 137 study patients, 42 (31%) had spontaneous NSVT on 24-h Holter. Compared with patients without NSVT, patients with NSVT on Holter had a higher New York Heart Association (NYHA) functional class (NYHA III: 40 vs. 18%, p < 0.01), a lower ejection fraction (29 +/- 9 vs. 34 +/- 9%, p = 0.01), and an increased LV end-diastolic diameter (69 +/- 8 mm vs. 66 +/- 7 mm, p = 0.03). The HRV variables rMSSD, pNN50, RRm, and BRS did not differ significantly between patients with and without spontaneous NSVT. Only SDNN on Holter was slightly lower in patients with versus without NSVT (106 +/- 45 vs. 121 +/- 46 ms, p = 0.08). CONCLUSIONS: Patients with IDC and spontaneous NSVT on Holter are characterized by a higher NYHA functional class, a lower LV ejection fraction, an increased LV end-diastolic diameter, and a tendency toward a lower SDNN value compared with patients without NSVT. The remaining measures of HRV including rMSSD and pNN50 reflecting primarily tonic vagal activity, as well as BRS reflecting predominantly reflex vagal activity, were similar in patients with and without NSVT. The prognostic significance of these findings in patients with IDC is currently under investigation in the Marburg Cardiomyopathy Study (MACAS) at our institution.     

冠心病维持性血液透析患者心率减速力与心率变异性的分析

目的 测定心率减速力与心率变异性指标,分析维持性血液透析的冠心病患者自主神经功能变化.方法选择35例维持性血液透析的冠心病患者,与年龄、性别相匹配的35例肾功能正常的冠心病患者及35例心脏、肾功能正常者进行比较,采集24 h动态心电图的DC值和HRV各指标值进行统计分析.结果三组间DC值、SDNN、rMSSD和pNN50比较,差异具有统计学意义(P＜0.05);维持血液透析组与肾功能正常组 DC、SDNN、rMSSD和pNN50指标低于对照组(P＜0.05);维持血液透析组与肾功能正常组间DC值、SDNN、rMSSD和pNN50比较,差异无统计学意义(P＞0.05).结论维持血液透析的冠心病患者自主神经功能降低,但与肾功能正常的冠心病患者相比差异无统计学意义.     

肝硬化患者的心率减速力与心率变异性分析

目的：探讨肝硬化患者的自主神经功能改变。方法对肝硬化组90例和正常对照组78例患者进行心率变异性（HRV）时域分析和心率减速力（DC）分析。结果肝硬化组与正常对照组比较,SDNN、SDANN、rMSSD、pNN50显著降低（P ＜0．01）,DC 值明显降低（P ＜0．05）。对于不同 Child-pugh 分级的肝硬化患者,肝硬化病变程度越重,HRV 各项指标值和 DC 值降低越明显。结论不同分级肝功能损害的病毒性肝炎肝硬化患者均可发生自主神经功能异常。     

Changes of Heart Rate Variability After Coronary Bypass Grafting

Background: Heart rate variability (HRV) may serve as a follow-up parameter in patients with coronary artery disease undergoing percutaneous transluminal angioplasty. Several studies have shown significant changes of HRV parameters in the case of restenosis. The value of this method as a prognostic parameter in patients following coronary artery bypass grafting (CABG) is unknown. Methods: In the present study we investigated changes of HRV parameters in patients undergoing CABG to prove whether this method would predict the outcome in these patients. Twenty patients (six female, 14 male, age 51–75 years, mean 62 years) with angiographically documented coronary artery disease (1 × 1-vessel disease, 10 × 2-vessel disease, 9 × 3-vessel disease) were investigated. Eight patients had previous myocardial infarction: 3 × anterior infarction and 5 × inferior infarction. Before and after CABG 24-hour measurement of HRV was performed using Holler monitoring (elapsed time between the two measurements 218 ± 92 days). All patients underwent successful CABG with complete revascularization. The following time domain parameters were calculated: SDNN, SDNN index, SDANN, r-MSSD and pNN50. Results: These parameters showed a significant decrease after CABG (P < 0.05) except rMSSD, which was below the statistic level. The results of the patients without previous myocardial infarction suggested that the parasympathetically influenced paramenters r-MSSD and pNN50 were mainly involved, while in the subgroup with previous myocardial infarction the sympathetically influenced parameters (SDNN, SDANN) were significantly changed. Other variables such as ejection fraction or severity of coronary artery disease did not influence the HRV results. Conclusions: In contratst to patients with revascularization by PTCA, HRV does not seem to be a suitable predictive parameter in patients after successful CABG. Intrinsic operative alterations with injury of cardiac nerves may be responsible for this observation.     

健康儿童心率变异性长程时域指标的

目的探讨健康儿童心率变异性(HRV)长程时域指标的特点。方法对266例健康儿童HRV24小时长程时域指标（SCL、SDNN、SDNNindex、SDANN、RMSSD、三角指数）进行不同年龄、性别及与成人正常参考值间进行分析比较。结果①儿童不同性别组间HRV差异无显著性;②儿童不同年龄组间虽心动周期（或心率）存在差异,但HRV差异无显著性;③儿童组与成人正常参考值中SDNN、SDANN、RMSSD存在有差异显著性,RMSSD在儿童中明显高于成人组。结论SDANN、SDNNindex是反映交感神经功能的敏感指标,而RMSSD更能反映迷走神经功能,可见儿童的自主神经功能较成人活跃,而随着年龄的增长即自主神经功能的减退,尤其是迷走神经的紧张性抑制功能明显减退。     

索他洛尔对室性早搏患者心率变异性的影响

目的　通过观察室性早搏患者在用索他洛尔治疗前后室性早搏及HRV的变化 ,以了解索他洛尔对室性早搏及HRV的影响。方法　对 5 0例室性早搏病人在索他洛尔治疗前后用动态心电图时域分析法对心率变异性各项指标进行了检测 ,并与对照组 5 0例进行比较。结果　与对照组进行比较 ,代表心率总变异程度的SDNN、SDANNI和SDNNI明显下降 (P <0 0 1) ,代表迷走神经功能的指标rMSSD、pNN5 0也有下降 (P <0 0 5 )。治疗组用药后与用药前比较显示对室性早搏有效率 70 % ,HRV的SDNN、SDANNI、SDNNI、rMSSD和 pNN50 均有所下降 (P <0 0 5 )。结论　索他洛尔不但能减少室性早搏 ,改善症状 ,而且能提高心率变异性 ,改善预后。     

冠心病Lorenz散点图与时域指标分析

目的探讨冠心病患者心率变异性（HRV）检测中Lorenz散点图与时域指标的相关性及诊断价值.方法检测70例冠心病患者动态心电图Lorenz散点图和时域指标,并与70例正常人做对比.结果与对照组比较,冠心病组的SDNN、SDANN及Lorenz散点图长度（L）均显著下降,正常对照组散点图94.28%呈彗星状,冠心病组鱼雷状、复杂形、梭状及三角状分别占28.57%、15.71%、12.86%及11.43%;L与SDNN、SDANN呈显著正相关,散点图离散度（D）与rMSSD、PNN50呈显著正相关.Lorenz散点图异常的敏感性和准确度明显高于SDNN＜100ms的指标.结论与时域指标相比,Lorenz散点图对HRV的变化敏感性更高,可作为判断冠心病患者HRV的重要手段.