Effects of 6-minute walk test on the QT dispersion in patients with congestive heart failure

Objective: To investigate the clinical value of QT dispersion (QTd) and the effects of 6-minute walk test (6-MWT) mimicking the patients' daily activities on QTd in patients with congestive heart failure (CHF).Methods: Twenty-eight CHF patients and 22 normal subjects participated these study, who all completed 6-MWT without developing severe arrhythmias.Before and after 6-MWT, standardized 12-lead surface ECGs were obtained to measure QTd and corrected QTd (QTcd).Results: Both before and after 6-MWT, the QTd and QTcd in CHF patients were longer than those in the controls (P<0.001), and QTd and QTcd after 6-MWT were significantly shorter than those before 6-MWT in CHF patients (P=0.007, and 0.018).There was no significant difference in the measurement in the control group.Conclusion: QTd and QTcd are longer in CHF patients than in normal subjects.Moderate exercise may improve the inhomogeneity of ventricular repolarization dispersion in CHF patients.

Effect of reperfusion strategy on QT dispersion in patients with acute myocardial infarction:Impact on in-hospital arrhythmia

BACKGROUND Myocardial ischemia and ST-elevation myocardial infarction(STEMI)increase QT dispersion(QTD)and corrected QT dispersion(QTcD),and are also associated with ventricular arrhythmia.AIM To evaluate the effects of reperfusion strategy[primary percutaneous coronary intervention(PPCI)or fibrinolytic therapy]on QTD and QTcD in STEMI patients and assess the impact of the chosen strategy on the occurrence of in-hospital arrhythmia.METHODS This prospective,observational,multicenter study included 240 patients admitted with STEMI who were treated with either PPCI(group I)or fibrinolytic therapy(group II).QTD and QTcD were measured on admission and 24 hr after reperfusion,and patients were observed to detect in-hospital arrhythmia.RESULTS There were significant reductions in QTD and QTcD from admission to 24 hr in both group I and group II patients.QTD and QTcD were found to be shorter in group I patients at 24 hr than those in group II(53±19 msec vs 60±18 msec,P=0.005 and 60±21 msec vs 69+22 msec,P=0.003,respectively).The occurrence of in-hospital arrhythmia was significantly more frequent in group II than in group I(25 patients,20.8%vs 8 patients,6.7%,P=0.001).Furthermore,QTD and QTcD were higher in patients with in-hospital arrhythmia than those without(P=0.001 and P=0.02,respectively).CONCLUSION In STEMI patients,PPCI and fibrinolytic therapy effectively reduced QTD and QTcD,with a higher observed reduction using PPCI.PPCI was associated with a lower incidence of in-hospital arrhythmia than fibrinolytic therapy.In addition,QTD and QTcD were shorter in patients not experiencing in-hospital arrhythmia than those with arrhythmia.

高强韧QT800-5材质的研究与应用

以铸态高强韧珠光体球铁的开发与应用为研究目标,使用万能材料试验机和金相显微镜分析了球墨铸铁经多元合金化及二次孕育处理后的组织和和性能。结果表明,同时添加Ni、Cu、Mo后,采用二次孕育(倒包孕育+随流孕育),可获得95%珠光体、2级球化等级、6级大小石墨的基体组织。其抗拉强度≥854 MPa、屈服强度≥537 MPa、延伸率≥6%,满足了高强韧球铁的力学性能要求。

Prolonged QT dispersion in inflammatory bowel disease

AIM:To investigate the frequency and factors of prolonged QT dispersion that may lead to severe ventricular arrhythmias in patients with inflammatory bowel disease(IBD).METHODS:This study included 63 ulcerative colitis(UC) and 41 Crohn's disease(CD) patients.Forty-seven healthy patients were included as the control group.Heart rate was calculated using electrocardiography,corrected QT dispersion(QTcd) and the Bazett's formula.Homeostasis model assessment(HOMA) was used to determine insulin resistance(IR).HOMA values < 1 were considered normal and values > 2.5 indicated a high probability of IR.RESULTS:Prolonged QTcd was found in 12.2% of UC patients,and in 14.5% of CD patients compared with the control group(P < 0.05).A significant difference was found between the insulin values(CD:10.95 ± 6.10 vs 6.44 ± 3.28,P < 0.05;UC:10.88 ± 7.19 vs 7.20 ± 4.54,P < 0.05) and HOMA(CD:2.56 ± 1.43 vs 1.42 ± 0.75,P < 0.05;UC:2.94 ± 1.88 vs 1.90 ± 1.09,P < 0.05) in UC and CD patients with and without prolonged QTcd.Disease behavior types were determined in CD patients with prolonged QTcd.Increased systolic arterial pressure(125 ± 13.81 vs 114.09 ± 8.73,P < 0.01) and age(48.67 ± 13.93 vs 39.57 ± 11.58,P < 0.05) in UC patients were significantly associated with prolonged QTcd.CONCLUSION:Our data show that IBD patients have prolonged QTcd in relation to controls.The routine followup of IBD patients should include determination of HOMA,insulin values and electrocardiogram examination.

Both transmural dispersion of repolarization and of refractoriness are poor predictors of arrhythmogenicity： a role for iCEB （QT/QRS）？

We read the original article by Nuis, et al. and the reply by Dogan, et al. with great interest. Nuis, et al. examined whether transcatheter aortic valve implantation （TAVI） in patients suffering from severe aortic stenosis led to changes in corrected QT dispersion （cQTD）, previously used to predict arrhythmic risk. Dogan, et al. proposed that a different marker, transmural dispersion of repolariza- tion （TDR）, has better accuracy in risk prediction.

Simulation on dissolute and dust dispersion in comprehensive mechanized heading face with forced-exhaust ventilation

According to the characteristics of comprehensive mechanized heading face, established the mathematical model of single-phase air flow with κ-ε two equations model, and have established κ-ε-θ-κp mathematic model to solve two-phase flow of gas and particles in dust space with eulerian-eulerian method and eulerian-lagrangian method. Numerical solution of gas-particle two-phase flow was put forward based on collocated grid SIMPLE algorithm. Moreover, numerical simulation of dust concentration in fully mechanized caving face was carded out by using Fluent software. Finally, when in forced-exhaust ventilation circumstance, drawer type fan drum have less dust absorption, and most of dust spread to the other site; the dust concentration is inversely proportional to the distance from tunneling head, and the dust concentration has already diffused to decrease below 102 mg/m3 at the position ofx=12 m. Dust are more focused on relative side（in the range about y from 0 to 2 meter） of roadway space of press-ventilated fan drum, especially between tunneling place and drawer type fan drum; the roadway with road header have a higher dust concentration. These conclusions provide reliable theory basis for the dust prevention in comprehensive mechanized heading face.

Effect of transcatheter aortic valve implantation on QT dispersion in patients with aortic stenosis

Background QT dispersion （QTd） is a predictor of ventricular arrhythmia. Ventricular arrhythmia is an important factor influencing morbidity and mortality in patients with aortic stenosis. Surgical aortic valve replacement reduced the QTd in this patients group. However, the effect of transcatheter aortic valve implantation （TAVI） on QTd in patients with aortic stenosis is unknown. The aim of this study was to investigate the effect of TAVI on QTd in patients with aortic stenosis. Methods Patients with severe aortic stenosis, who were not candi-dates for surgical aortic valve replacement due to contraindications or high surgical risk, were included in the study. All patients underwent electrocardiographic and echocardiographic evaluation before, and at the 6th month after TAVI, computed QTd and left ventricular mass index （LVMI）. Results A total 30 patients were admitted to the study （mean age 83.2 ± 1.0 years, female 21 and male 9, mean valve area 0.7 ± 3 mm2）. Edwards SAPIEN heart valves, 23 mm （21 patients） and 26 mm （9 patients）, by the transfemoral approach were used in the TAVI procedures. All TAVI procedures were successful. Both QTd and LVMI at the 6th month after TAVI were significantly reduced com-pared with baseline values of QTd and LVMI before TAVI （73.8 ± 4 ms vs. 68 ± 2 ms, P=0.001 and 198 ± 51 g/m2 vs. 184 ± 40 g/m2, P=0.04, respectively）. There was a significant correlation between QTd and LVMI （r=0.646, P〈0.001）. Conclusions QTd, which malign ventricular arrhythmia marker, and LVMI were significantly reduced after TAVI procedure. TAVI may decrease the possibility of ventricu-lar arrhythmia in patients with aortic stenosis.

外周血25-(OH)-D、D-二聚体及QT离散度与支气管肺炎患儿心肌损伤标志物的相关性

目的 探究外周血25-羟维生素D[25-(OH)-D]、D-二聚体及QT离散度与支气管肺炎患儿心肌损伤标志物的相关性。方法 前瞻性选取2020年1月至2022年1月池州市第二人民医院收治的45例支气管肺炎伴心肌损伤患儿纳入研究组,另按照1∶1的比例随机抽取45例在本院接受治疗的支气管肺炎未发生心肌损伤患儿纳入对照组。对两组患儿的心肌损伤标志物[肌酸激酶(CK)、肌酸激酶同工酶(CK-MB)、肌钙蛋白T(cTnT)及N-末端脑钠肽前体(NT-proBNP)]水平进行记录,采用Pearson相关性分析探究患儿心肌损伤标志物水平与外周血25-(OH)-D、D-二聚体及QT离散度的相关性;采用受试者操作特征(ROC)曲线探究上述指标对支气管肺炎患儿发生心肌损伤的诊断价值。结果 研究组患儿的CK、CK-MB、cTnT及NT-proBNP水平分别为(185.46±18.33) U/L、(62.45±8.44) U/L、(1.89±0.36)μg/mL、(287.65±45.12) ng/L,均高于对照组患儿[(82.22±11.02) U/L、(20.58±4.15) U/L、(0.44±0.12)μg/mL、(122.45±25.15) ng/L],差异均有统计学意义(P<0.05)。研究组患儿25-(OH)-D水平为(53.45±6.11) nmol/L,低于对照组[(74.45±5.15) nmol/L],D-二聚体、QT离散度水平分别为(3.98±1.18)μg/mL、(33.18±1.98) ms,均高于对照组[(2.11±0.54)μg/mL、(25.15±2.16) ms],差异均有统计学意义(P<0.05)。经Pearson相关性分析可知,患儿的CK、cTnT、CK-MB及NT-proBNP水平均与25-(OH)-D水平呈负相关(P<0.05),与D-二聚体、QT离散度水平呈正相关(P<0.05)。经ROC曲线分析可知,外周血25-(OH)-D、D-二聚体、QT离散度均对支气管肺炎患儿心肌损伤具有一定诊断价值,其曲线下面积值分别为0.854、0.843、0.894、0.827(P<0.05)。结论 支气管肺炎患儿25-(OH)-D、D-二聚体、QT离散度与其心肌损伤存在显著相关性,且各指标对支气管肺炎并发心肌损伤均存在一定诊断价值。

QT Dispersion and QTc Interval in Patients with Adult Sickle Cell Disease: Electrocardiographic (EKG) and Echocardiographic Evaluation

Background: QT dispersion (QTd) varies according to heterogeneity of recovery time in the myocardium, and the impact of iron overload on the QTd in adult patients with Sickle Cell Disease (SCD) is not clear. Aim: This cross-sectional study was designed to evaluate corrected QTc interval and QTd on 12 leads ECG in patients with SCD, and assess the LV systolic and diastolic function using Pulsed Doppler Echocardiogram. Method: All patients were evaluated clinically with pulse Doppler echocardiography. Twelve leads ECG were taken to measure QTd and QTc. Blood samples withdrawn to assess the blood level of ferritin and hemoglobin. Pearson correlation coefficient was used to measure the linear relationship between serum ferritin and QTd. Results: The study included patients with SCD (n = 70, age 15.7 ± 8.9 years), compared with age-matched healthy control group (n = 70, age 15.9 ± 8.9 years). In patients with SCD compared with healthy control group the QTc (msec) 416 ± 23.21 ms vs. 401 ± 24.12 (p = 0.75), and the QTd were slightly longer in SCD compared with the control of 43 ± 22.1 vs. 38 ± 20.16 msec, (p = 0.071) with no significant difference. M mode echo showed that SCD patients compared with control had higher LVMI gm/M2 of 105 ± 10.3 vs. 83 ± 7.1, P = 0.001, larger LV end diastolic dimension (cm) of 5.5 ± 0.32 vs. 4.72 ± 0.35, p = 0.03, RV diameter (cm) of 2.8 ± 0.42 vs. 2.4 ± 0.31, (p = 0.041) and RV wall thickness (mm) of 0.31 ± 0.06 vs. 0.28 ± 0.03, (p = 0.024). Pulsed Doppler showed high LV transmitral E wave velocity of 85.23 ± 1.92 vs. 62.43 ± 1.67 m/s (p = 0.001), A wave (msec) 46.26 ± 4.7 vs. 56.24 ± 3.2 m/s, p = 0.032, with E/A ratio of 1.86 ± 0.01 vs. 1.10 ± 0.03, (p = 0.024) and DT of E wave (msec) of 156.43 ± 23.5 vs. 189.87 ± 19.5, (p = 0.031). Left ventricle ejection fraction percentage was similar between both groups, but SCD had significantly higher right ventricle tricuspid annular plane systolic excursion TAPSE (cm) of 1.23 ± 0.21 vs. 1.11 ± 0.23 cm (p = 0.02), and the tricuspid valve velocity showed significant higher velocity (m/s) in the SCD patients of 2.9 ± 0.14 vs. 1.7 ± 0.09, p = 0.004 indicating higher pulmonary artery pressure with calculated right ventricle systolic pressure of 38.64 vs. 16.56 mmHg. Conclusion: SCD patients compared with control have higher but not significant QT dispersion and corrected QT interval with a significantly larger LV mass and LV diastolic filling indices suggestive of restrictive diastolic pattern. These data indicate that LV diastolic abnormalities compromised initially in patients with SCD.

Defective recovery of QT dispersion following transcatheter aortic valve implantation： frequency, predictors and prognosis

Background Corrected QT dispersion （cQTD） has been correlated with non-uniform ventricular repolarisation and increased mortality. In patients with aortic stenosis, cQTD has been shown improved after surgical valve replacement, but the effects of transcatheter aortic valve implantation （TAVI） are unknown. Therefore, we sought to explore the frequency, predictors and prognostic effects of defective cQTD recovery at 6 months after TAVI. Methods A total of 222 patients underwent TAVI with the Medtronic-CoreValve System between November 2005 and January 2012. Patients who were on class Ⅰ or Ⅲ antiarrhythmics or on chronic haemodialysis or who developed atrial fibrillation, a new bundle branch block or became pacemaker dependent after TAVI were excluded. As a result, pre-, post- and follow-up ECG （median： 6 months） analysis was available in 45 eligible patients. Defective cQTD recovery was defined as any progression beyond the baseline cQTD at 6 months. Results In the 45 patients, the mean cQTD was 47 ± 23 ms at baseline, 45 ±17 ms immediately after TAVI and 40 ± 16 ms at 6 months （15% reduction, P = 0.049）. Compared to baseline, cQTD at 6 months was improved in 60% of the patients whereas defective cQTD recovery was present in 40%. cQTD increase immediately after TAVI was an independent predictor of defective cQTD recovery at 6 months （per 10 ms increase; OR： 1.89, 95% CI： 1.15-3.12）. By univariable analysis, defective cQTD recovery was associated with late mortality （HR： 1.52, 95% CI： 1.05-2.17）. Conclusions Despite a gradual reduction ofcQTD after TAVI, 40% of the patients had defective recovery at 6 months which was associated with late mortality. More detailed ECG analysis after TAVI may help to avoid late death.

Matrix Solid-phase Dispersion Extraction of Alkaloids from the Roots of Aconitum kusnezoffii Reichb

Matrix solid-phase dispersion（MSPD） was developed for the extraction of four alkaloids, including aconitine, mesaconitine, hypaconitine and deoxyaconitine, from the roots ofAconitum kusnezoffii Reichb. The determination of the analyte was carried out by high performance liquid chromatography with UV detection. The alkaline alumina was used as sorbent. The mixture of acetonitrile and water was used as elution solvent. Several extraction parameters, such as type of sorbent, the ratio of sample to solid support material, type of the elution solvent and the volume of the elution solvent were tested. Mean recoveries ranged from 93.16% to 102.73%, with relative standard deviations from 0.27% to 4.17%. With the extraction efficiency and time expenditure taken into account, MSPD extraction should be a comparatively good method.

增材制造Co-Cr-W合金修复QT400-18球墨铸铁发动机机体的抗穴蚀性能研究

为提高球墨铸铁发动机机体的表面性能,解决使用过程中空泡溃灭产生的穴蚀问题,分别采用激光熔覆和氩弧焊在QT400-18球墨铸铁表面进行Co-Cr-W钴基合金层的增材修复,并对熔覆层和堆焊层试样的组织、硬度、室温拉伸性能、抗穴蚀性能进行分析。结果表明:修复层主要为细小的、交错生长的柱状晶和树枝晶,激光熔覆层的组织比氩弧焊层组织更细密,硬度更高;这两种修复层试样的抗拉强度和基体接近,但塑性下降;经8 h穴蚀后,QT400-18基体损伤严重,激光熔覆试样和氩弧焊试样的表面较光滑,其抗穴蚀性能明显提高,激光熔覆试样和氩弧焊试样的失重相比球墨铸铁基体分别降低95.32%、93.58%。

QT500-7球墨铸铁汽车制动钳与支架反白口产生原因

某QT500-7球墨铸铁汽车制动钳与支架日常检验中出现两种不同特征的反白口缺陷,采用宏观观察、化学成分分析、金相检验、显微硬度测试、扫描电镜与能谱分析等方法对反白口缺陷的产生原因进行分析。结果表明:成分偏析是制动钳试样反白口缺陷形成的主要原因,而成分偏析和孕育衰退是支架试样反白口缺陷形成的主要原因;制动钳试样存在反石墨化元素的偏析,增大了铁水的过冷倾向,从而形成反白口缺陷;支架试样中心区域存在孕育衰退,加上反石墨化元素的偏析,使试样形成反白口缺陷。

EFFECTS OF AMIODARONE AND SOME CLASS ⅠAGENTS ON QT DISPERSION

Objective To investigate the elfects of some class Ⅰ antiarrhythmic agents on QT dispersion and compared with those of amiodarone. Methods Group I was composed of 30 cases, they were all treated with class Ⅰ agents. The drugs used include: mexiletine (8 cases), moricizine (9), propafenone (12) and apridine (1). GrouP Ⅱ was composed of other 30 patients, and were all treated with amiodarone. The ddlerences of QT intervals between ECG leads (QTd and QTcd) were measured belore and aler medication. Results Before medication, the QTmax and QTcmax in group Ⅱ were signilicantly longer than those of group Ⅰ, resulting in greater QTd and QTcd in grouP Ⅱ (QTd:66± 14ms vs 31± 16ms, P<0.01; QTcd:71±36ms vs 44± 18ms, P<0.01). Alter medication, QTmax and QTcmax of group Ⅰ were prolonged, leading to the lengthening of QTd (from 31±16ms to 45±17ms, P<0.01) and QTcd (from 44± 18 ms to 58± 21ms, P<0.05), indicating the increase of inhomogeneity of myocardial repolarization after the treatment of class Ⅰ agents. Alter amiodarone treatment, QTmin and QTmax in grouP Ⅱ were both prolonged, with a greater amplitude of QTmin prolongation, resulting in decreased QTd and QTcd in group Ⅱ (QTd /rom 66± 14ms to 36±22ms, P<0.01, QTcd from 71±36ms to 45±27ms, P<0.01). The signifcant dofference of QTd and QTcd between two groups disappeared aler medication. Conclusion The results of the present study may relect the opposite effects of amiodarone and these class Ⅰ agents on myocardial repolarization.

QT interval dispersion in the patients with central serous chorioretinopathy

AIM: To evaluate QT dispersion(QTD) in patients with central serous chorioretinopathy(CSC).METHODS: This clinical, comperative, case-control study included 30 patients with CSC at acute phase(Group 1) and 30 age- and sex-matched healthy subjects(Group 2, the control group). From all subjects, a 12-lead surface electrocardiography was obtained. The heart rate(HR), QT maximum(QT max), QT minimum(QT min), QT corrected(QT c), QTD and T mean were manually measured and analyzed. Student’s t-test and Pearson’s method of correlation were used for statistical analysis.· RESULTS: The patient and control groups were matched for age, smoking status(rate and duration) and gender. There were no significant differences with regard to these among the groups(P 】0.05). The participants included 19 men(63.3%) and 11 women(36.7%) in Group1, 20 men(66.7%) and 10 women(33.3%) in Group 2.QT max, QTD and QT c were significantly higher than those of healthy controls(P 【0.001 for QT max, P =0.01 for QTD and P =0.001 for QT c). QT min, T mean and HR did not differ significantly between the study groups(P =0.28 for QT min,P =0.56 for T mean and P 】0.05 for HR). No significant correlation was found between duration of the disorder and QTD values(r =0.13, P 】0.05).CONCLUSION: These findings suggest that CSC may be associated with an increase in QTD and that the patients might be at risk for ventricular arrhythmia.

Sb微合金化QT600-10铸件的生产技术

研究了一种低成本Sb微合金化QT600-10铸件生产技术,并分析了Sb含量对铸件显微组织和力学性能的影响。结果表明,通过控制铁液化学成分,并添加适量Sb,采用合理的球化和孕育工艺,可以获得符合QT600-10标准的铸件,其珠光体含量可达55%.Sb的添加促进了石墨的圆整化,并随着Sb含量的增加,珠光体含量也增加,从而显著提高了铸件的抗拉强度、屈服强度和硬度。然而,当Sb含量超过0.008 wt.%时,铸件的延伸率将无法满足QT600-10标准的要求。本研究为低成本生产高性能QT600-10铸件提供了一种新的技术途径。

Si、Mn、Cu含量对高硅固溶球墨铸铁QT600-10铸件组织及强度的影响

为了提高高硅固溶球墨铸铁QT600-10铸件的性能,分析了不同含量的Si、Mn、Cu对铸件组织及强度的影响。结果表明:Si、Mn、Cu含量的变化对铸件珠光体含量变化无显著的对应关系;Mn含量在0.34%~0.40%,未发现对铸件强度有显著影响(可能范围过窄);Si含量在3.87%~4.24%,铸件强度随Si含量的增加而增加,当Si含量低于3.95%时,铸件强度会低于600 MPa,Si含量在4.24%时,铸件强度为629 MPa,是本次试验的最高强度;Cu含量在0.18%~0.44%,随着Cu含量的增加,铸件强度反而降低。

QT400-18L风电球墨铸铁件铸造工艺改进

针对QT400-18L风电球墨铸铁件,进行铸造工艺改进。在铸件底部、铸件内圈以及铸件外圈部位均匀放置外冷铁,增加铸型的激冷能力,减小金属液凝固区域,加快金属液结晶、凝固冷却速度。设计专用浇口杯结构,减少铁液与空气的接触面,有效防止气体和熔渣卷入型腔,减轻液流对树脂砂型腔的冲击。控制砂型(芯)的硬度,减小石墨自膨胀。烘烤砂型,型腔水分,降低形成气孔的倾向。优化熔炼过程,获得更多石墨球的致密组织。通过上述工艺措施,有效预防了风电QT400-18L球墨铸铁件缩孔、疏松缺陷,提高了球墨铸铁件的成品率,降低了成本,成功完成了4.2MW前、后压盖等圆环类厚壁铸件的生产任务。

工程机械电驱动桥铸件QT600-10铸态材质开发

针对电驱动桥铸件铸态材质的高强度和高韧性特点,通过选取合适的化学成分,采取铁水净化和孕育措施,利用虚拟仿真软件优化铸造工艺,开发出满足QT600-10标准的Y试块和满足QT600-8标准的本体材料。

QT Dispersion Level and Its Clinical Significance in Dilated Cardiomyopathy

Objective To evaluate the clinical significance of QT dispersion (QTd, QTcd) in dilated cardiomyopathy (DCM). Methods QTd and QTcd were measured on simultaneously recording 12 lead electrocardiograms (ECGs) in 60 DCM patients and compared with 60 healthy subjects. Results The values of QTd and QTcd in DCM were significantly higher than those in control group (P<0 01). With subgroup analysis, QTd and QTcd in patients with cardiac sudden death (CSD) were longer than those in survivors and those died of progressive heart failure (P<0 05), patients with ventricular tachycardia (VT) or with severe heart failure than those without (compared with patients with ventricular premature beats [VPB], P<0 05, compared with patients without ventricular arrhythmia [VA], P<0 01) or with mild heart failure (P<0 01). The values of QTd and QTcd in patients with VPB were greater than those in patients without VA(P<0 05). There were significant differences in the rates of VT, CSD and heart failure between the groups of QTd>110 ms and QTd≤110 ms(P<0 01 or P<0 05), in contrast to ejection fraction(EF) and fractional shortening (FS)(P>0 05). Conclusion The values of QTd and QTcd increased in DCM patients were susceptive index for monitoring maligant VA in DCM, also important prognostic markers of CSD. QTd was correlated with NYHA functional class but not with EF and FS.