QT离散度对慢性充血性心力衰竭的临床意义

本文分析６６例ＮＹＨＡ分级法心功能Ⅲ－Ⅳ级的慢性充血性心力衰竭患者治疗前后ＱＴ离散度，并与正常组对照，结果表明：１．ＣＨＦ组较正常对照组ＱＴｄ显著延长，不同病因组间无差异；２．住院观察期间，ＱＴｄ在非持续性室速组及死于慢性心衰的病人组无显著延长，１例心性猝死者ＱＴｄ显著处长；３．治疗好转后ＱＴｄ呈下降趋势，治疗无效，恶化者ＱＴｄ进一步延长。     

老年充血性心力衰竭患者QT离散度的临床意义

ＱＴ离散度 (ＱＴｄ)反映心室肌复极的不均一性 ,在许多心脏病中具有预测恶性心律失常的价值。我们观察了 65例老年人充血性心力衰竭病人的ＱＴｄ ,以探讨ＱＴｄ在老年充血性心力衰竭患者中的临床意义。1　资料与方法选择近 2年资料较完整的住院老年充血性心力衰竭患者共 65例 ,其中男 43例 ,女 2 2例 ,年龄 60～82 (平均 68 4)岁 ,平均心衰病程 5 5年。按ＮＹＨＡ心功能分级标准 ,心功能Ⅳ级 46例 (70 8% ) ,心功能Ⅲ级3 1例 (2 9 2 % ) ;超声心动图检查发现均有心脏扩大 ,平均左室舒张末期内径 (ＬＶＤ)为(66± 5 2 )ｍｍ。室性心律失…     

充血性心力衰竭患者测定QT离散度的意义

充血性心力衰竭（ＣＨＦ）患者预后不佳，心脏性猝死（ＳＣＤ）是引起ＣＨＦ患者死亡的主要原因之一，约占３０％～５０％。近年研究表明，ＣＨＦ发生猝死者ＱＴ离散度（ＱＴｄ）显著增加。本文通过对４５例ＣＨＦ患者心电图分析并与３０例正常人对照，随访２４月～２６月...     

充血性心力衰竭患者QT离散度与室性心律失常的关系

<正> 近几年来,人们发现QT间期离散度(QTd)具有一定的临床意义.本文分析100例重度(心功能Ⅲ、Ⅳ级)充血性心力衰竭(CHF)患者QTd与严重室性心律失常的关系.1 对象与方法1.1 对象全部病例均系本院住院患者.根据Framingham心力衰竭诊断标准,确诊为充血性心力衰竭;按NYHA分级评定心功能,随机选择心功能Ⅲ、Ⅳ级患者为观察对象.共观察101例,男性76例,女性24例,平均年龄59.3岁.     

稳心颗粒对充血性心力衰竭患者QT间期离散度的影响

选择92例充血性心力衰竭患者,随机分为对照组和治疗组各46例,治疗组在基础治疗基础上加用稳心颗粒.分别观察两组治疗后QT间期离散度(QTd)和校正的QTd(QTcd)的变化.发现与治疗前比较,治疗后两组QTd和QTcd均明显缩短(P<0.01),且治疗组缩短幅度均明显大于对照组(P<0.01).认为稳心颗粒能有效缩短充血性心力衰竭患者QTd,改善心室肌复极均一性和电活动稳定性.     

充血性心力衰竭患者P波离散度与QT离散度的关系及意义

目的探讨慢性充血性心力衰竭(CHF)患者P波离散度(Pd)与QT离散度(QTd)的关系及意义。方法选择CHF患者43例为观察组,正常人41例为对照组,窦性心率下测量体表12导联心电图的Pd和QTd进行分析。结果①CHF组的Pd和QTd明显大于对照组(P<0.01);②Pd与QTd呈显著正相关(r=0.43,P<0.05);③QTd>100ms组Pd明显大于QTd<100ms组(P<0.05)。结论在CHF患者中Pd与QTd存在相关性,这对CHF患者发生心律失常的病理生理、预测和治疗等可能有一定意义。     

充血性心力衰竭患者QT离散度和血镁的变化

充血性心力衰竭（ＣＨＦ）是一种常见的临床综合征。一般认为ＣＨＦ死亡的病例中约４７％［１］为心源性猝死,而且常源于室性心律失常。如何识别猝死的高危患者是临床医师面临的一个重要问题。ＱＴ间期离散度（ＱＴｄ）是指ＱＴ间期在体表心电图各导联之间的差异程度,它反映了心室复极过程的不均匀性,可用来预测室性心律失常的发生。作者对８６例ＣＨＦ患者测定ＱＴｄ及血镁浓度,旨在了解ＣＨＦ患者ＱＴｄ的变化,并观察ＱＴｄ与血镁的关系。１　对象与方法１．１　对象　ＣＨＦ组８６例ＣＧＦ患者,男５５例,女３１例,年龄４０岁～７…     

美托洛尔对充血性心力衰竭患者QT离散度的影响及临床意义

目的探讨美托洛尔对充血性心力衰竭（CHF）患者QT离散度的影响及临床意义。方法将56例CHF患者随机分为治疗组（28例）和对照组（28例）,对照组采用常规治疗,治疗组在常规治疗的基础上加用美托洛尔,并作治疗前后的QTd测量及比较。结果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〈0.05）;给予美托洛尔治疗后CHF患者QTd明显缩短（P〈0.05）。结论CHF患者QTd明显增大。美托洛尔可使QTd缩小,对防治室性心律失常和猝死有重要意义。     

The effects of chronic carvedilol therapy on QT dispersion in patients with congestive heart failure.

BACKGROUND: Carvedilol therapy reduces mortality from sudden cardiac death and progressive pump failure in congestive heart failure (CHF). However, the effect(s) of carvedilol on ventricular repolarization characteristics is unclear. AIM: The aim of the study was to investigate the effects of chronic carvedilol therapy on ventricular repolarization characteristics as assessed by QT dispersion (QTd) in patients with CHF. METHOD: Nineteen patients (age 53+/-12 years; 16 male, three female) with CHF (eight ischemic, 11 non-ischemic dilated cardiomyopathy) were prospectively included in the study. Carvedilol was administered in addition to standard therapy for CHF at a dose of 3.125 mg bid and uptitrated biweekly to the maximum tolerated dose. From standard 12-lead electrocardiograms the maximum and minimum QT intervals (QTmax, QTmin), QTd, corrected QT intervals (QTcmax, QTcmin) and corrected QTd (QTcd) values were calculated at baseline, after the 2nd and the 16th month of carvedilol therapy. RESULTS: A significant reduction was noted in the QTd and QTcd values with carvedilol therapy after the 16th month (QTd: 81+/-22 ms vs. 40+/-4.3 ms P<0.001; QTcd: 91+/-25 ms vs. 51+/-7 ms P<0.001), but not after the 2nd month (P>0.05). The resting heart rate was also significantly reduced after a 16-month course of carvedilol therapy (78+/-13 bpm vs. 66+/-15 bpm, P<0.05). Carvedilol therapy did not alter QTmax and QTcmax intervals (P>0.05), however, QT min and QTcmin significantly increased with carvedilol at the 16th month (P<0.001 and P<0.01, respectively). CONCLUSION: Long-term carvedilol therapy was associated with a reduction in QTd, an effect that might contribute to the favorable effects of carvedilol in reducing sudden cardiac death in CHF.     

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。     

Right lateral decubitus position reduces QT dispersion in patients with chronic heart failure

A greater QT dispersion in patients with chronic heart failure (CHF) appears to be a non-invasive marker of susceptibility to malignant ventricular arrhythmias. We evaluated whether QT dispersion in CHF patients is modified by the patients' recumbent position. In 12 CHF patients, and age and sex-matched 12 normal subjects, a single 12-lead surface ECG was recorded in each postural position [left lateral decubitus position (L), supine position (S), and right lateral decubitus position (R)]. In normal subjects, the QT dispersion was comparable in the three recumbent positions [L: 47+/-15 (SD) ms, S: 40+/-9 ms, R: 38+/-14 ms, P=NS]. In contrast, in CHF patients, QT dispersion was significantly shorter in R than those in L and S (L: 93+/-42 ms*, S: 81+/-29 ms*, R: 63+/-24 ms, *P <.05 vs. R). In conclusion, reclining in R reduces the prolonged QT dispersion in CHF patients.     

慢性心衰并低钾血症QT离散度与室性心律失常的关系

目的：了解心衰并低血钾时校正QT离散度（QTcd)与室性心律失常的关系。方法：分别测量健康对照组。单纯心衰组、心衰并低血钾组及其血钾纠正后的QTcd，并进行比较，同时对各组室性心律失常发生率进行比较。结果：心衰并低血钾组QTcd及室性心律失常发生率明显高于血钾纠正后及单纯心衰组的（P＜0．05－0．01）。结论：QTcd可作为监测心衰并低血钾时室性心律失常危险性的指标。     

QT dispersion in patients with chronic heart failure: beta blockers are associated with a reduction in QT dispersion

OBJECTIVE: To compare QT dispersion in patients with impaired left ventricular systolic function and in matched control patients with normal left ventricular systolic function. DESIGN: A retrospective, case-control study with controls matched 4:1 for age, sex, previous myocardial infarction, and diuretic and beta blocker treatment. SETTING: A regional cardiology centre and a university teaching hospital. PATIENTS: 25 patients with impaired left ventricular systolic function and 100 patients with normal left ventricular systolic function. MAIN OUTCOME MEASURES: QT and QTc dispersion measured by three methods: the difference between maximum and minimum QT and QTc intervals, the standard deviation of QT and QTc intervals, and the "lead adjusted" QT and QTc dispersion. RESULTS: All measures of QT/QTc dispersion were closely interrelated (r values 0.86 to 0.99; all p < 0.001). All measures of QT and QTc dispersion were significantly increased in the patients with impaired left ventricular systolic function v controls (p < 0.001): 71.9 (6.5) (mean (SEM)) v 46.9 (1.7) ms for QT dispersion, and 83.6 (7.6) v 54.3 (2.1) ms(-1-2) for QTc dispersion. All six dispersion parameters were reduced in patients taking beta blockers (p < 0.05), regardless of whether left ventricular function was normal or impaired-by 9.4 (4.6) ms for QT dispersion (p < 0.05) and by 13.8 (6. 5) ms(-1-2) for QTc dispersion (p = 0.01). CONCLUSIONS: QT and QTc dispersion are increased in patients with systolic heart failure in comparison with matched controls, regardless of the method of measurement and independently of possible confounding factors. beta Blockers are associated with a reduction in both QT and QTc dispersion, raising the possibility that a reduction in dispersion of ventricular repolarisation may be an important antiarrhythmic mechanism of beta blockade.     

Effect of dofetilide on QT dispersion and the prognostic implications of changes in QT dispersion for patients with congestive heart failure

AIMS: Drug-induced changes in QT dispersion may be a way of detecting harmful repolarisation abnormalities for patients receiving antiarrhythmic drugs affecting ventricular repolarisation. METHODS AND RESULTS: In 463 congestive heart failure (CHF) patients enrolled in the Danish Investigations Of Arrhythmia and Mortality On Dofetilide-CHF (DIAMOND-CHF) study, both pre-treatment and on-treatment day 2-6 QT dispersion was available from standard 12-lead ECGs. Patients were randomised in a double-blind manner to receive either placebo or dofetilide, a new class III antiarrhythmic drug. During a median follow-up of 19 months (minimum 1 year), 179 patients (39%) died (135 patients from cardiac causes). Changes in QT dispersion did not predict all-cause or cardiac mortality for patients treated with dofetilide in multivariate survival analysis (Risk ratio: 1.02, 95% confidence interval: 0.97-1.08, P>0.4). This finding was independent of pre-treatment QT dispersion. Dofetilide caused a small QT dispersion increment of 8 ms, not different from the changes seen in the placebo group (3 ms). CONCLUSION: For patients with CHF and reduced left ventricular systolic function, changes in QT dispersion following treatment with dofetilide do not predict all-cause or cardiac mortality. The dofetilide-induced QT dispersion changes are small and comparable to those seen in placebo treated patients.     

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     

Serious adverse events experienced by patients with chronic heart failure taking spironolactone

In patients with chronic heart failure, spironolactone added to conventional treatment may lead to serious and, occasionally, fatal hyperkalaemia. In some cases this seems to happen because spironolactone causes diarrhoea. Four cases involving men with New York Heart Association functional class III heart failure are presented. As these cases revealed, close monitoring of blood chemistry is mandatory after starting spironolactone, and patients should be advised to stop spironolactone immediately if diarrhoea develops.     

心率减速力及 QT 离散度对慢性心力衰竭患者心源性猝死的预测价值

目的：探讨心率减速力（deceleration capacity,DC）及 QT 离散度（QT dispersion,QTd）对慢性心力衰竭（chronic heart failure,CHF）患者心源性猝死的预测价值。方法随机选择慢性心力衰竭患者100例（心衰组）,随访一年,根据有无室性心律失常分为室性心律失常组（43例）和非室性心律失常组（57例）;根据有无心源性猝死分为猝死组（18例）和生存组（82例）。同期100例在本院体检健康者作为对照组。测定各组患者早期 DC 值和 QTd 值,进行统计分析。结果心衰组、室性心律失常组及猝死组患者的 DC 和 QTd 值分别和对照组、非室性心律失常组及生存组比较,差异均有统计学意义（P ＜0．05）。慢性心力衰竭患者的 QTd 与 DC 呈负性相关。结论慢性心力衰竭患者的 DC 和 QTd 值与病情严重程度有关,可作为预测慢性心力衰竭患者发生心源性猝死的敏感指标。