QT,JT离散度对扩张型心肌病患者猝死的预测价值

测定了３１例扩张型心肌病患者（下称患者组）与２０例健康者（下称对照组）体表１２导联心电图的ＱＴ离散度（ＱＴｄ）和ＪＴ离散度（ＪＴｄ），并随访１２￣２０个月。结果显示，猝死心肌病患者（１１例）的ＱＴｄ、ＪＴｄ明显高于心衰死亡者、存活者及对照组（Ｐ均〈０．０１）。因心衰死亡者的ＱＴｄ、ＪＴｄ明显高于对照组（Ｐ均〈０．０１），与存活患者无明显差异（Ｐ均〉０．０５）。ＪＴｄ〈６０ｍｓ、６０ｍｓ〈ＪＴｄ〈１     

急性心肌梗塞早期QT间期离散度、JT间期离散度增加与近期预后的关系

测定１０７例急性心肌梗塞（ＡＭＩ）患者第三心肌梗塞日的ＱＴ间期离散度（ＱＴｄ）和ＪＴ间期离散度（ＪＴｄ）．并以１００例正常人作对照。结果显示：ＡＭＩ组ＱＴｄ、ＪＴｄ较对照组显著增大（均Ｐ＜０．００１）。住院期间死亡组（３Ｏ例）ＱＴｄ与ＪＴｄ较存活组（７７例）明显增大（均Ｐ＜０．００１）。提示以ＱＴｄ、ＪＴｄ增大来评价ＡＭＩ患者的近期预后有一定意义。     

老年急性心肌梗塞QT离散度变化及临床意义

目的探讨老年急性心肌梗塞（ＡＭＩ）早期心电图ＱＴ离散度（ＱＴｄ）变化特点，ＱＴｄ与临床表现的关系，以及ＱＴｄ对预后的意义。方法测量老年ＡＭＩ组和非老年ＡＭＩ组各５０例及老年无心脏病组５４例１２导联心电图ＱＴｄ（ＪＴｄ），即ＱＴ间期（ＪＴ）最大值与最小值之差，计算出ＱＴｃｄ（ＪＴｃｄ）。结果老年ＡＭＩ组ＱＴｄ（ＪＴｄ）与其他２组分别有非常显著性差异（Ｐ＜０．００５～０．００１）。两ＡＭＩ组死亡与生存者ＱＴｄ（ＪＴｄ）均有显著、非常显著性差异（Ｐ＜０．０５～０．０１）。老年ＡＭＩ组重度泵衰竭、室性心律失常发生率及死亡率高于非老年ＡＭＩ组。结论ＱＴｄ（ＪＴｄ）可作为判断ＡＭＩ患者病情与预后的一项有价值的指标，对老年ＡＭＩ患者更具有临床意义。     

导管射频消融对QT、JT离散度的影响

目的研究导管射频消融术（ＲＦＣＡ）对ＱＴ、ＪＴ离散度（ＱＴｄ、ＪＴｄ）的影响。方法测量６２例阵发性室上性心动过速和４例特发性室速患者ＲＦＣＡ术前、术后的ＱＴｄ、ＪＴｄ。结果所有患者术前、术后ＱＴｄ、ＪＴｄ无显著差异（Ｐ均＞０．０５），三组不同电生理机制的室上速患者之间术后ＱＴｄ、ＪＴｄ差异无显著性（Ｐ均＞０．０５）。结论ＰＦＣＡ不影响正常心室肌复极离散度。     

急性心肌梗死QT离散度和JT离散度与心功能的相关性

作者测定分析１００例急性心肌梗死（ＡＭＩ）患者住院第３ｄ的１７导联心电图ＱＴ间期离散度（ＱＴｄ）及ＪＴ间期离散度（ＪＴｄ），并以１００例正常人作对照。结果表明:ＡＭＩ组的ＱＴｄ及ＪＴｄ较正常组明显增大，差异非常显著（Ｐ＜０．０１）。ＡＭＩ泵功能级别（Ｋｉｌｉｐ分法）与ＱＴｄ及ＪＴｄ呈正相关，即泵功能级别愈高，则ＱＴｄ，ＪＴｄ值愈大（ｒ分别为０．９９与０．９５）。     

QT间期离散度在扩张型心肌病严重心功能不全患者预后中的意义

目的：探讨ＱＴ间期离散度（ＱＴｄ）和（或）ＪＴ间期离散度（ＪＴｄ）的增加与扩张型心肌病严重心功能不全患者远期预后的关系。方法：测定２６例扩张型心肌病（ＮＹＨＡＩＩ～ＩＶ级）患者与２０例健康者体表１２导联心电图的ＱＴｄ及ＪＴｄ。并对全部患者随访１６～３８个月。结果：２６例扩张型心肌病患者心性死亡１７例（６５．４％）。死亡组ＱＴｄ及ＪＴｄ分别为７８．７±４２．４和８０．７±３８．６ｍｓ，明显高于存活组（４７．８±２０．６和５０．２±１６．１ｍｓ）和正常对照组（３９．６±１２．２和４２．５±１５．１ｍｓ），差异有显著性（Ｐ均＜０．０５）。ＱＴｄ＜６０ｍｓ、６０ｍｓ＜ＱＴｄ＜１００ｍｓ和ＱＴｄ＞１００ｍｓ的死亡率分别为３３．３％，７５．０％和１００％，差异显著（Ｐ＜０．０５），猝死率分别为０％、１６．７％和１００％，差异非常显著（Ｐ＜０．００１）。结论：ＱＴｄ明显增加的患者远期死亡率显著高于ＱＴｄ正常或轻度增加的患者，并可能与猝死发生有关。提示ＱＴｄ（或ＪＴｄ）可作为判断预后的独立参数。     

83例心源性死亡患者QTd、JTd测定结果分析

临床观察发现，ＱＴ离散度（ＱＴｄ）、ＪＴ离散度（ＪＴｄ）增大与缺血性心脏病猝死有关。我们对８３例心源性死亡患者的ＱＴｄ、ＪＴｄ进行了分析，旨在探讨ＱＴｄ、ＪＴｄ与猝死的关系。资料与方法：观察组为８３例于住院期间死亡的心源性疾病患者。其中猝死（猝死组）...     

急性心肌梗塞患者溶栓治疗对QT离散度和JT离散度的影响

观察４８例急性心肌梗塞（ＡＭＩ）患者静脉溶栓治疗前后ＱＴ离散度（ＱＴｄ）、ＪＴ离散度（ＪＴｄ）的变化，结果显示，溶栓成功组ＱＴｄ、ＪＴｄ较溶栓前显著减少而非成功级ＱＴｄ、ＪＴｄ较溶栓前无显著性差异，因此，ＱＴｄ、ＪＴｄ可作为判断溶栓成功的参数指标之一。     

老年冠心病患者QT离散度变化及其临床意义

目的探讨老年冠心病患者ＱＴ离散度（ＱＴｄ）和心率校正的ＱＴ离散度（ＱＴｃｄ）与致命性室性心律失常（ＦＶＡ）及心衰（ＨＦ）之间的关系。方法测定了８４例老年冠心病患者的ＱＴｄ及ＱＴｃｄ，其中心原性猝死（ＣＳＤ）９例，ＦＶＡ２３例，非ＦＶＡ６１例。有ＨＦ４７例，无ＨＦ３７例。结果ＣＳＤ组ＱＴｄ、ＱＴｃｄ显著大于ＦＶＡ及非ＦＶＡ组（Ｐ＜０．０５；Ｐ＜０．０１），ＦＶＡ组ＱＴｄ、ＱＴｃｄ大于非ＦＶＡ组（Ｐ＜０．０１），ＨＦ组ＱＴｄ、ＱＴｃｄ显著长于无ＨＦ组（Ｐ＜０．０１）。本文ＱＴｄ和ＱＴｃｄ呈显著正相关（ｒ＝０．９７２０，Ｐ＜０．０１）。结论作者认为ＱＴｄ和（或）ＱＴｃｄ可作为评估老年冠心病患者发生ＦＶＡ和（或）ＨＦ预后的重要参考指标。     

冠心病患者的心室晚电位、室性早搏与心肌复极离散度的关系

对７０例冠心病患者和２１例健康人的心电图数值进行测量，并对心室晚电位、室性早搏与心电图各测值的关系进行研究。结果：①心绞痛和陈旧性心肌梗塞患者ＱＴｃ、ＱＴｄ、ＪＴ、ＪＴｃ、ＪＴｄ及ＪＴｃｄ明显高于健康对照组（Ｐ＜０．０５或＜０．０１）。陈旧性心肌梗塞组患者ＱＴｃ、ＱＴｄ、ＱＴｃｄ及ＪＴｄ、ＪＴｃｄ高于心绞痛组（Ｐ＜０．０５或＜０．０１）。②心室晚电位阳性的冠心病患者的ＱＴｄ、ＱＴｃｄ、ＪＴｄ、ＪＴｃｄ明显高于心室晚电位阴性的冠心病组（Ｐ＜０．０５或＜０．０１）。③冠心病伴室性早搏者ＱＴｃ、ＱＴｄ、ＱＴｃｄ、ＪＴ、ＪＴｃ、ＪＴｄ、ＪＴｃｄ明显增加（Ｐ＜０．０５或＜０．０１）。提示冠心病存在明显心肌复极不均匀，心室晚电位和室性早搏与心肌复极离散度有关。     

QT and JT Dispersion in Children with Long QT Syndrome

QT and JT Dispersion in Long QT Syndrome. Introduction: Abnormalities of ventricular repolarization leading to ventricular arrhythmias place children with long QT syndrome at high risk for sudden death. Dispersion of the QT (QTd) and JT (JTd) intervals, as markers of cardiac electrical heterogeneity, may be helpful in evaluating children with long QT syndrome and identifying a subset of patients at high risk for development of critical ventricular arrhythmias (ventricular tachycardia, torsades de pointes, and/or cardiac arrest). Methods and Results: The QTd and JTd intervals in 39 children with long QT syndrome were compared to those of 50 normal age-matched children. In the long QT syndrome group, QTd measured 81 ± 70 msec compared to 28 ± 14 msec in the control group (P < 0.05), and JTd in the long QT syndrome group was 80 ± 69 msec compared to 25 ± 15 msec in the control group (P < 0.05). Conclusion: Children with long QT syndrome have an increased QTd and JTd when compared to normal controls. A QTd or JTd ≥ 55 msec correlates with the presence of critical ventricular arrhythmias. These ECG measures of dispersion can be useful in stratifying children with the long QT syndrome who are at higher risk for developing critical ventricular arrhythmias.     

慢性心衰猝死患者QT离散度的变化

本文观察研究慢性心衰(观察组),和无心脏病病人(对照组)各60例的QT离散度。发现观察组的QT离散度较对照组大。而观察组中心衰猝死者(11例)的QT离散度明显大于观察组心衰存活组(30例)、心衰进展死亡组(19例)的QT离散度(P<0.001)。并发现心衰猝死组QT离散度的增大与心功能分级、电解质的血清浓度无相关性。慢性心衰猝死组QTd均值为96.81ms.提示QT离散度的明显增大,是慢性心衰发生猝死的一项具有警告性的重要标志。     

QT dispersion in patients with arrhythmogenic right ventricular dysplasia.

AIMS: Arrhythmogenic right ventricular dysplasia is a rarely diagnosed cardiomyopathy, but a frequent cause of ventricular arrhythmia and sudden cardiac death. QT interval dispersion, measured as an interlead variability of QT, is a marker of dispersion of ventricular repolarization and, hence, of electrical instability. The present study was conducted to assess the occurrence of QT dispersion and its modulation during treatment with sotalol.Methods Twenty-five patients with the diagnosis of arrhythmogenic right ventricular dysplasia were studied retrospectively. Fourteen patients were considered low risk for malignant ventricular arrhythmia and sudden cardiac death, and 11 high risk due to documented sustained ventricular arrhythmia, cardiac arrest, or sudden cardiac death. Twenty five healthy volunteers served as control subjects. RESULTS: Dispersion of repolarization was significantly higher in patients than in control subjects (QTd and JTd: P<0.05). Dispersion of repolarization was equal in patients both with and without malignant arrhythmias. There was no significant change in dispersion after treatment with sotalol. Adjacent QT dispersion between leads V3-V4, V4-V5 and V5-V6, respectively, was higher in patients than in control subjects (P<0. 05), while no differences were seen in leads V1-V2 and V2-V3. CONCLUSION: QT interval dispersion is increased in patients with arrhythmogenic right ventricular dysplasia. However, the degree of dispersion is not related to the severity of symptoms, nor is it influenced by treatment with sotalol.     

Effects of aerobic exercise training on indices of ventricular repolarization in patients with chronic heart failure.

BACKGROUND: Patients with chronic heart failure (CHF) have a markedly increased incidence of malignant ventricular arrhythmias. QT dispersion (QTd), defined as the difference between maximal and minimal QT intervals, reflects the regional inhomogeneity of ventricular repolarization dispersion and may mark the presence of malignant ventricular arrhythmias. PURPOSE: To determine the effects of exercise training on QTd in patients with CHF. PATIENTS: Fifteen patients with CHF and ejection fractions < 40% (mean, 28+/-9%) who were on a stable medical regimen. DESIGN AND INTERVENTION: Standardized 12-lead surface ECGs were obtained at the beginning and end of the exercise training program, and QT and JT intervals were measured manually and corrected for heart rate by using Bazett's formula. QTd, heart rate-corrected QTd (QTc-d), JT dispersion (JTd), and heart rate-corrected JTd (JTc-d) were measured in at least eight ECG leads in each patient. RESULTS: Following the cardiac rehabilitation and exercise training programs, patients with CHF had only slight improvements in exercise capacity (results were not significant). However, these patients had marked improvements in QTd (71+/-11 to 59+/-17 ms; p < 0.02), QTc-d (82+/-28 to 63+/-17 ms; p < 0.01), JTd (76+/-19 to 57+/-18 ms; p < 0.002), and JTc-d (84+/-23 to 61+/-18 ms; p < 0.001) following the exercise training programs. CONCLUSION: These data indicate that aerobic exercise training significantly reduces the indices of ventricular repolarization dispersion in patients with CHF. Further studies are needed to evaluate how effectively this reduction in ventricular repolarization dispersion decreases the risk of malignant ventricular arrhythmias and sudden death in patients with CHF.     

充血性心力衰竭QT离散度变化及美托洛尔对其影响

目的 :测定充血性心力衰竭 （CHF）患者的 QT离散度 （QTd）及美托洛尔对 QTd的影响。方法 :110例 CHF患者和 5 0例健康人同时作 QTd测量 ,CHF患者中 38例进行美托洛尔治疗 ,与未使用美托洛尔的 78例作比较。结果 :CHF患者的 QTd明显高于健康人 （P<0 .0 1） ;QTd与心功能受损的程度呈正相关 ;CHF伴室性心律失常者QTd大于不伴室性心律失常者 （P<0 .0 5 ） ;予美托洛尔治疗后 CHF患者 QTd明显缩短 （P<0 .0 5 ）。结论 :CHF患者 QTd明显增大。美托洛尔可使 QTd缩小 ,对防治严重心律失常和猝死有重要意义     

Influence of biventricular pacing on myocardial dispersion of repolarization in dilated cardiomyopathy patients.

AIMS: The aim of our study was to evaluate the effect of cardiac resyncronization therapy on QT dispersion (QTd), JT dispersion (JTd), and transmural dispersion of repolarization (TDR), markers of heterogeneity of ventricular repolarization in a study population with severe heart failure. METHODS AND RESULTS: Fifty patients (43 male, 7 female, age 60.2+/-3.1 years) suffering from congestive heart failure (n=39 NYHA class III; n=11 NYHA class IV) as a result of coronary artery disease (n=19) or of dilated cardiomyopathy (n=31), with sinus rhythm (SR), QRS duration >120 ms (mean QRS duration=156+/-21 ms), an ejection fraction <35%, left ventricular end-diastolic diameter >55 mm, presence of atrioventricular asynchrony, intra- and inter-ventricular asynchrony, underwent permanent biventricular pacemaker implantation. A 12-lead standard electrocardiogram was performed at baseline, during right-, left-, and biventricular pacing (BiVP) and QTd, JTd, and TDR were assessed. BiVP significantly reduced QTd (73.93+/-19.4 ms during BiVP vs. 91+/-6.7 ms in SR, P=0.004), JTd (73.18+/-17.16 ms during BiVP vs. 100.72+/-39.04 at baseline, P=0.003), TDR (93.16+/-15.60 vs. 101.55+/-19.08 at baseline, P<0.004), compared with SR. Right ventricular endocardial pacing and left ventricular epicardial pacing both increased QTd (RVendoP 94+/-51 ms, P<0.03; LVepiP 116+/-71 ms, P<0.02), and TDR (RVendoP 108.13+/-19.94 ms, P<0.002; LVepiP 114.71+/-26.1, P<0.05). There was no effect on JTd during right and left ventricular stimulation. CONCLUSIONS: BiVP causes a statistically significant reduction of ventricular heterogeneity of repolarization and has an electrophysiological anti-arrhythmic influence on the arrhythmogenic substrate of dilated cardiomyopathy.     

Repolarization dispersion and sudden cardiac death in patients with impaired left ventricular function

AIMS: Prolongation of repolarization dispersion measured from the12-lead surface ECG has been associated with sudden cardiacdeath and ventricular tachyarrhythmia in a variety of heartdisorders. This study tested the hypothesis that increased repolarizationdispersion is of prognostic value in identifying chronic heartfailure patients at high risk of sudden cardiac death and ventriculartachyarrhythmia. RESULTS: In 163 patients, ischaemic (n=126) and idiopathic dilated (n=37)cardiomyopathy with a left ventricular ejection fraction 40%were diagnosed by left ventricular angiography. During follow-up(26±15 months) 24 patients died suddenly, 10 experiencedventricular tachyarrhythmia, 19 died from pump failure, sixdied from acute myocardial infarction, and 97 survived. Bazett'sformula rate-corrected JT-interval dispersion (JTc-d) was foundto be 109±23 ms in sudden cardiac death/ventricular tachyarrhythmiapatients, 57±20 ms in survivors, and 55+20 ms in patientswho died from pump failure or acute myocardial infarction. Bothunivariate and multivariate analyses showed JTc-d to be themost important independent predictor of sudden cardiac death/ventriculartachyarrhythmia. A cut-off value of 85 ms for JTc-d had a 74%positive and a 98% negative predictive accuracy in identifyingpatients at risk for sudden cardiac death/ventricular tachyarrhythmia. CONCLUSION: Analysis of repolarization dispersion from the 12-lead surfaceECG seems to be a useful screening method for identifying chronicheart failure patients at high risk for sudden cardiac death/ventriculartachyarrhythmia.     

急性颅脑损伤患者心电图QT离散度的特点与意义

目的探讨急性颅脑损伤（ABI）患者心电图QT、JT间期变化对其轻重程度的判断及预后评估的意义。方法根据格拉斯哥昏迷评分,将101例ABI患者分为轻、中、重型三组;根据患者有无蛛网膜下腔出血（SAH）,分为SAH组及无SAH组。检测各组伤后24h内心电图的QT间期及JT间期,计算QT离散度（QTd）、校正的QT离散度（QTcd）、JT离散度（JTd）及校正的JT离散度（JTcd）;根据格拉斯哥预后评分判断预后,对其不同组间的各值进行统计学分析。结果轻、中、重型ABI患者的心电图QTd、QTcd、JTd、JTcd存在显著性差异,且SAH组各指标均升高,较无SAH组有显著统计学差异（P〈0．01或〈0．05）,并与预后有明显的相关性（P均〈0．01）。结论QTd、QTcd、JTd、JTcd对判断ABI程度及其预后评估有重要参考价值,可作为预测患者临床转归的指标,并且有助于早期临床干预。