Corrected QT interval in cirrhosis:A systematic review and metaanalysis

BACKGROUND Corrected QT(QTc)interval is prolonged in patients with liver cirrhosis and has been proposed to correlate with the severity of the disease.However,the effects of sex,age,severity,and etiology of cirrhosis on QTc have not been elucidated.At the same time,the role of treatment,acute illness,and liver transplantation(Tx)remains largely unknown.AIM To determine the mean QTc in patients with cirrhosis,assess whether QTc is prolonged in patients with cirrhosis,and investigate whether QTc is affected by factors such as sex,age,severity,etiology,treatment,acute illness,and liver Tx.METHODS In the present systematic review and meta-analysis,the searching protocol“{[QTc]OR[QT interval]OR[QT-interval]OR[Q-T syndrome]}AND{[cirrhosis]OR[Child-Pugh]OR[MELD]}”was applied in PubMed,EMBASE,and Google Scholar databases to identify studies that reported QTc in patients with cirrhosis and published after 1998.Seventy-three studies were considered eligible.Data concerning first author,year of publication,type of study,method used,sample size,mean age,female ratio,alcoholic etiology of cirrhosis ratio,Child-Pugh A/B/C ratio,mean model for end-stage liver disease(MELD)score,treatment withβ-blockers,episode of acute gastrointestinal bleeding,formula for QT correction,mean pulse rate,QTc in patients with cirrhosis and controls,and QTc according to etiology of cirrhosis,sex,Child-Pugh stage,MELD score,and liver Tx status(pre-Tx/post-Tx)were retrieved.The Newcastle-Ottawa quality assessment scale appraised the quality of the eligible studies.Effect estimates,expressed as proportions or standardized mean differences,were combined using the randomeffects,generic inverse variance method of DerSimonian and Laird.Subgroup,sensitivity analysis,and meta-regressions were applied to assess heterogeneity.RESULTS QTc combined mean in patients with cirrhosis was 444.8 ms[95%confidence interval(CI):440.4-449.2;P<0.001 when compared with the upper normal limit of 440 ms],presenting high heterogeneity(I2=97.5%;95%CI:97.2%-97.8%);both Egger’s and Begg’s tests showed non-significance.QTc was elongated in patients with cirrhosis compared with controls(P<0.001).QTc was longer in patients with Child-Pugh C cirrhosis when compared with Child-Pugh B and A(P<0.001);Child-Pugh B patients presented longer QTc when compared with Child-Pugh A patients(P=0.003).The MELD score was higher in patients with cirrhosis with QTc>440 ms when compared with QTc≤440 ms(P<0.001).No correlation of QTc with age(P=0.693),sex(P=0.753),or etiology(P=0.418)was detected.β-blockers shortened QTc(P<0.001).QTc was prolonged during acute gastrointestinal bleeding(P=0.020).Tx tended to improve QTc(P<0.001).No other sources of QTc heterogeneity were revealed.CONCLUSION QTc is prolonged in cirrhosis independently of sex,age,and etiology but is correlated with severity and affected byβ-blockers and acute gastrointestinal bleeding.QTc is improved after liver Tx.

A Case Study of Severe QT Interval Prolongation Caused by Antidepressants

QT interval prolongation can be categorized into primary and secondary types according to its etiology.In this paper,we report a case of severe asymptomatic QT interval prolongation secondary to antidepressants.Regular follow-up and electrocardiogram monitoring is crucial when applying antidepressants,especially for patients without cardiac symptoms.This article presents case studies and examines existing literature on long QT syndrome to enhance the diagnosis and management of QT interval prolongation.This is especially relevant for non-psychiatric healthcare professionals who need to be attentive to the side effects of antidepressants to prevent potential adverse consequences resulting from oversight.

Left ventricular hypertrophy amplifies the QT,and Tp-e intervals and the Tp-e/QT ratio of left chest ECG

Objective： To evaluate the changes in Tp-e interval （an interval from the peak to the end of the T wave）, QT interval and Tp-e/QT ratio of the body surface ECG in patients with left ventricular hypertrophy （LVH）. Methods： The Tp-e interval and QT interval were measured on body surface ECGs in 42 patients without either hypertension or LVH （control group）, 41 patients having hypertension but not LVH （non-LVH group）, and 38 patients with both hypertension and LVH （LVH group）. Results： The mean corrected QT （QTc） interval, and mean corrected Tp-e[T（p-e）c] interval were significantly longer in the LVH group （0.430±0.021s vs. 0.409±0.019s, p 〈 0.01; 0.098±0.013s vs. 0.088±0.011s, respectively） than those in the control group. The Tp-e/QT ratio was also amplified in LVH group （0.232± 0.028 vs.0.218± 0.027） （p 〈 0.05）. Conclusion： LVH increased the QT interval, Tp-e interval and Tp-e/QT ratio of the body surface ECG.

回顾性分析住院患者心电图QT间期延长的科室分布及病因

目的分析住院患者心电图出现QT间期延长的科室分布及病因。方法入选2019年1月30日至2022年7月27日于海军军医大学(第二军医大学)第一附属医院接受心电图检查且诊断为长QT间期(校正QT间期≥500 ms)的患者61例,收集患者基线资料,分析所在科室及引起QT间期延长的病因。结果61例QT间期延长住院患者中冠心病、高血压、糖尿病和肿瘤分别占50.8%(31例)、45.9%(28例)、23.0%(14例)和8.2%(5例)。QT间期延长患者的住院科室主要集中在急诊科(45.9%,28例)和心血管内科(31.1%,19例)。QT间期延长的病因主要为药物(44.3%,27例)、冠心病(26.2%,16例)及电解质紊乱(24.6%,15例)。引起QT间期延长的药物中,常见的药物为Ⅲ类抗心律失常药、抗生素(喹诺酮类和大环内酯类)及5-羟色胺受体拮抗剂等。61例QT间期延长住院患者中,有3例(4.9%)发生尖端扭转型室性心动过速,6例(9.8%)住院期间死亡。结论住院患者中,QT间期延长多见于急诊科和心血管内科,绝大多数为获得性QT间期延长,常见的病因包括药物、冠心病及电解质紊乱等。

Nomenclature,categorization and usage of formulae to adjust QT interval for heart rate

Assessment of the QT interval on a standard 12 lead electrocardiogram is of value in the recognition of a number of conditions. A critical part of its use is the adjustment for the effect of heart rate on QT interval. A systematic search was conducted to identify studiesthat proposed formulae to standardize the QT interval by heart rate. A nomenclature was developed for current and subsequent equations based on whether they are corrective(QTc) or predictive(QTp). QTc formulae attempt to separate the dependence of the length of the QT interval from the length of the RR interval. QTp formulae utilize heart rate and the output QTp is compared to the uncorrected QT interval. The nomenclature consists of the first letter of the first author's name followed by the next two consonance(whenever possible) in capital letters; with subscripts in lower case alphabetical letter if the first author develops more than one equation. The single exception was the Framingham equation,because this cohort has developed its own "name" amongst cardiovascular studies. Equations were further categorized according to whether they were linear,rational,exponential,logarithmic,or power based. Data show that a person's QT interval adjusted for heart rate can vary dramatically with the different QTc and QTp formulae depending on the person's heart rate and QT interval. The differences in the QT interval adjustment equations encompasses values that are considered normal or significant prolonged. To further compare the equations,we considered that the slope of QTc versus heart rate should be zero if there was no correlation between QT and heart rate. Reviewing a sample of 107 patient ECGs from a hospital setting,the rank order of the slope- from best(closest to zero) to worst was QTc DMT,QTc RTHa,QTc HDG,QTc GOT,QTcF RM,QTcF RD,QTcB ZT and QTcM YD. For two recent formulae based on large data sets specifically QTcD MT and QTcR THa,there was no significant deviation of the slope from zero. In summary a nomenclature permits easy reference to QT formulae that adjust for heart rate. Twenty different formulae can produce discordant calculations of an adjusted QT interval. While the formulae developed by Bazett and Fridericia(QTc BZT and QTc FRD respectively) may continue to be used clinically,recent formulae from large population studies specifically QTcD MT and QTcR THa appear to be betterto adjust QT for heart rate in clinical practice.

Liver cirrhosis-effect on QT interval and cardiac autonomic nervous system activity

AIM To examine the impact of liver cirrhosis on QT interval and cardiac autonomic neuropathy(CAN). METHODS A total of 51 patients with cirrhosis and 51 controls were examined. Standard 12-lead electrocardiogram recordings were obtained and QT as well as corrected QT interval(QTc) and their dispersions(dQT, dQTc) were measured and calculated using a computer-based program. The diagnosis of CAN was based upon the battery of the tests proposed by Ewing and Clarke and the consensus statements of the American Diabetes Association. CAN was diagnosed when two out of the four classical Ewing tests were abnormal. RESULTS QT, QTc and their dispersions were significantly longer(P < 0.01) in patients with cirrhosis than in controls. No significant differences in QT interval were found among the subgroups according to the etiology of cirrhosis. Multivariate regression analysis after controlling for age, gender and duration of cirrhosis demonstrated significant association between QT and presence of diabetes mellitus [standardized regression coefficient(beta) = 0.45, P = 0.02] and treatment with diuretics(beta = 0.55, P = 0.03), but not with the Child-Pugh score(P = 0.54). Prevalence of CAN was common(54.9%) among patients with cirrhosis and its severity was associated with the Child-Pugh score(r = 0.33, P = 0.02). Moreover, patients with decompensated cirrhosis had more severe CAN that those with compensated cirrhosis(P = 0.03). No significant association was found between severity of CAN and QT interval duration.CONCLUSION Patients with cirrhosis have QT prolongation. Treatment with diuretics is associated with longer QT. CAN is common in patients with cirrhosis and its severity is associated with severity of the disease.

肿瘤治疗患者的QT间期监测及临床风险评估

目前肿瘤治疗除常规的化疗外,还包括生物靶向治疗、内分泌治疗及免疫检查点抑制剂治疗等。伴随肿瘤治疗出现的心血管不良事件备受关注,其中QT间期延长是与许多肿瘤治疗药物相关的心室复极异常现象,可能会诱发尖端扭转型室性心动过速。目前已知的可影响QT间期的因素包括药物、心率、电解质紊乱等。本文结合国内外新近研究进展,对肿瘤治疗患者QT间期的测量、影响因素,QTc相关不良事件分级,可致QT间期延长的抗肿瘤药物及辅助治疗药物,肿瘤治疗患者QT间期的监测与管理策略进行综述。

基于代谢组学研究黄芪甘草汤调控SIRT1/FOXO1通路预防三氧化二砷诱导的QT间期延长的作用机制

目的:基于代谢组学探索黄芪甘草汤防治三氧化二砷诱导QT间期延长的保护作用及其机制。方法:建立三氧化二砷诱导大鼠QT间期延长模型。检测大鼠心电图、血常规、代谢组学差异代谢物,并结合网络药理学收集关键靶点,通过功能注释、通路富集分析筛选黄芪甘草汤保护作用的可能候选基因与通路,并进行体外实验验证。结果:黄芪甘草汤对三氧化二砷诱导的SD大鼠QT间期具有显著的缓解作用(P<0.05);GO富集分析发现黄芪甘草汤和三氧化二砷诱导QT间期延长的关键靶点主要涉及炎症应答、活性氧、氧化应激等生物过程,内细胞囊泡、褶皱、内细胞囊泡膜等细胞组分,SMAD结合、R-SMAD结合、信号受体激活剂的活性等分子功能;KEGG通路分析发现其主要富集于PI3K-Akt信号通路、脂质和动脉硬化、FOXO信号通路、TNF信号通路、HIF-1等信号通路。通过体外H9c2细胞模型,验证了黄芪甘草汤能够逆转SIRT1、FOXO1蛋白表达。结论:黄芪甘草汤可能通过调控SIRT1/FOXO1信号通路,从而改善三氧化二砷诱导QT间期延长,减轻三氧化二砷心脏毒性。

Prolonged QTc Interval Is an Electrophysiological Hallmark of Cirrhotic Cardiomyopathy

BACKGROUND: Cirrhotic Cardiomyopathy is a relatively ill-characterized condition, which is often under-diagnosed due to absence of defined diagnostic criteria. ECG showing corrected QT Interval prolongation is the most suitable available option for diagnosis of this condition. OBJECTIVE: To determine the frequency of corrected QT interval prolongation in patients with liver cirrhosis. METHODOLOGY: Patients (n = 166) with confirmed cirrhosis, 30 years or older, presented in the outpatient and emergency department of medicine at Capital Hospital Islamabad between 1 October 2011 and 30 September 2012, were enrolled in this cross-sectional study after taking consent. ECG was done using calibrated ECG machine, and the QT Interval was measured. Corrected QT was calculated using Bazett’s formula and a QTc of more than 0.44 seconds was considered as being prolonged. RESULTS: The mean age of the patients was 57.05 ± 12.03 years. The corrected QT Interval varied from 337 ms to 560 ms. The mean QTc Interval was 429.92 ms ± 45.11. QTc was prolonged in 41 out of 166 patients (24.7%). Frequency of QTc prolongation was 4.5% in Child Pugh Grade A, 23.2% in Child Pugh Grade B, and 32.0% in Child Pugh Grade C. Association of Child Pugh Scoring with QTc prolongation was determined and found to be statistically significant (P < 0.05). CONCLUSION: QTc interval was prolonged in 24.7% of cirrhotic patients in our study. There was a significant increase in frequency with worsening of Child Pugh Grade, thereby indicating an association between QTc prolongation and the severity of cirrhosis.

北京市92例药物引起心电图QT间期延长的不良反应分析

目的:了解北京市上报的药物引起心电图QT间期延长的不良反应报告,探讨药品不良反应(ADR)发生规律及特点,为临床安全用药提供参考依据。方法:收集2018—2022年北京市各机构上报的92例QT间期延长的ADR报告,对ADR类型、患者性别和年龄、原患疾病和既往不良反应史、涉及药品的药理分类、药品性质、药物剂型、临床转归等进行分析。结果:92例QT间期延长的ADR报告中,女性患者51例(占55.43%),男性患者41例(占44.57%);≥65岁患者最多,共41例(占44.57%)。涉及药品100例次,其中以抗感染药物(44例次)、抗精神病药(28例次)、心血管系统用药(10例次)为主;ADR例次数排序居前3位的药品为莫西沙星(32例次)、氨磺必利(15例次)、胺碘酮(7例次);有口服及注射剂型的药品共13种,其中静脉剂型导致的ADR 45例次,口服剂型导致的ADR 13例次。ADR转归方面,痊愈和好转的有79例(占85.87%)。结论:在注射抗感染药物、口服抗精神病药、口服心血管系统用药、有QT间期延长不良反应的药物联合应用时,尤其是老年人、女性、本身存在QT间期延长者,要重点关注患者心电图情况和临床症状体征,必要时采用信息化预警手段,通过优化治疗方案,防止QT间期延长的发生及进展,保障患者用药安全。

Detailed analysis of the impact of age on the QT interval

在 ECG QT 间隔，心血管的死亡的一个重要预言者和导致药的心脏的心律不齐上分析年龄的效果，并且决定是否QT心率修正公式( QTc )与年龄和 sex.MethodsData 的微分关系从 US 国家健康和营养考试调查( NHANES ) II 和 III 被检验了， 25～90 年的平民。QT 加权的工具和标准差被计算所有年龄。QTc 为六 QTc 被评估：求婚了由 Bazett (QTcBZT ) ， Fridericia (QTcFRD ) ，霍奇斯(QTcHDG ) ， Dmitrienko (QTcDMT ) ， Rautaharju (QTcRTHa ) 和 .ResultsQTc 是的 Framingham (QTcFRM ) 强烈与年龄和性有关，为所有公式除了为女人的 QTcBZT。在 QTc 和年龄之间的关系不管关系是否被接近由是重要的一线性或非线性(二次或立方的花键) 当模特儿。QTc 在男人与年龄更戏剧性地增加了。有一重要(P < 0.001 ) 在为为男人和女人的每个 QTc 公式的 QTc 变化和年龄之间的积极关系。特别有有有老年的更长的 QTc 的个人的一个更大的比例年龄 80 年和 above.ConclusionQTc 和它的变化与年龄增加。延长 QTc 在更老的个人是更流行的，特别男人。

Aging effects on QT interval： Implications for cardiac safety of antipsychotic drugs

ObjectivesTo 明确地在心脏的毒性上探索老化的效果年龄和抑制精神的药的相互作用与搜索策略用 OvidSP 平台被寻找改变 QT interval.MethodsThe Medline 数据库：“； QT interval”；或 “； QT”；并且 “； age”；或 “； aging”；。入口标准是：有两性上的数据的超过 10,000 个显然健康的个人；为心率(QTc ) 和它的变化的表情改正延续到更旧的 ages.ResultsQTc 的多重年龄十年的 QT 间隔与增加年龄在持续时间增加了。在正常人口在 QTc 认为谦虚的是 SD 增长，氯普马嗪的增加生产了比好久 70 岁以上的 450 ms 平均大的 QTc。Risperidone，那平均没改变 QTc，将被期望在一些情形下面在他们的 70 年中年里在人生产 450 ms 的 QTc。QTc 延伸 >；有抑制精神的药的 500 ms 在 99 th 百分位数。当与抑制精神的药导致的期望的 QT 间隔变化的范围结合了时，它可以与平均不在显然正常的老人或女人为 QT 间隔改变价值的 QTc.ConclusionsThe 范围的 Haloperidol 发生，能乐意地与延长 QTc 被联系。有在 99 th 百分位数可以与甚至不是的那些通常与 QTc 延伸联系了的抑制精神的药有严肃的 QTc 延伸。

Comparison of QT Correction Methods in the Pediatric Population of a Community Hospital: A Retrospective Study

Objective:Accurate measurement of QT interval,the ventricular action potential from depolarization to repolarization,is important for the early detection of Long QT syndrome.The most effective QT correction(QTc)formula has yet to be determined in the pediatric population,although it has intrinsically greater extremes in heart rate(HR)and is more susceptible to errors in measurement.The authors of this study compare six dif-ferent QTc methods(Bazett,Fridericia,Framingham,Hodges,Rautaharju,and a computer algorithm utilizing the Bazett formula)for consistency against variations in HR and RR interval.Methods:Descriptive Retrospective Study.We included participants from a pediatric cardiology practice of a community hospital who had an ECG performed in 2017.All participants were healthy patients with no past medical history and no regular med-ications.Results:ECGs from 95 participants from one month to 21 years of age(mean 9.7 years)were included with a mean HR of 91 beats per minute(bpm).The two-sample paired t-test or Wilcoxon signed-rank test assessed for any difference between QTc methods.A statistically significant difference was observed between every combination of two QTc formulae.The Spearman’s rank correlation analysis explored the QTc/HR and QTc/RR relationships for each formula.Fridericia method was most independent of HR and RR with the lowest absolute value of correlation coefficients.Bazett and Computer had moderate correlations,while Framingham and Rautaharju exhibited strong correlations.Correlations were positive for Bazett and Computer,reflecting results from prior studies demonstrating an over-correction of Bazett at higher HRs.In the linear QTc/HR regression analysis,Bazett had the slope closest to zero,although Computer,Hodges,and Fridericia had comparable values.Alternatively,Fridericia had the linear QTc/RR regression coefficient closest to zero.The Bland-Altman method assessed for bias and the limits of agreement between correction formulae.Bazett and Computer exhibited good agreement with minimal bias along with Framingham and Rautaharju.To account for a possible skewed distri-bution of QT,all the above analyses were also performed excluding the top and bottom 2%of data as sorted by heart rate ranges(N=90).Results from this data set were consistent with those derived from all participants(N=95).Conclusions:Overall,the Fridericia correction method provided the best rate correction in our pedia-tric study cohort.

Verapamil modulating arsenic trioxide-induced QT interval prolongation in guinea pig

Objective To investigate therapeutic action of verapamil on QT prolongation induced by arsenic trioxide (As2O3) in guinea pig and to further explore its possible mechanism. Methods Different doses of As2O3 was infused intravenously to observe the changes of QT interval on the electrocardiogram (ECG) at different times in guinea pig.Patch clamp technique and laser scanning confocal microscopy were utilized to study the action of As2O3 on action potential duration (APD),L-type calcium current (ICa-L), rapid delayed rectifier potassium current (IKr) and intracellular calcium concentration ([Ca2+]i) of guinea pig myocytes. At the same time, verapamil was applied preliminarily to evaluate effects of verapamil on changes of the above index induced by AS2O3 . Results Intravenous administration of As2O3 at the dose of 1.6mg/kg and 0.8mg/kg prolonged QT interval on ECG obviously in guinea pig hearts dose dependently and time de pendently. QTc (corrected QT interval) was progressively prolonged in the 2-hour period of intravenous infusion of 1.6mg/ kg As2O3 from (328 .5±30.9)ms of control to (388 .4±31. 3)ms at 2h following As2O3 (P < 0.01). When verapamil was pretreated for 5min,then 1.6mg/kg As2O3 was added,the results showed that QTc was shorter in verapamil-treatment group (357 .3±21 .4)ms than that in As2O3 group (388 .4±31.3)ms (P<0.05) at 2h.Confocal experiments showed that in normal Tyrode solution, As2O3 (1μmol/L and 10/μmol/L) had no obvious effects on resting [Ca2+ ]i( P > 0 .05) in guinea pig cardiomyoeytes,however, 10μmol/L As2O3 could markedly enhance [Ca2+ ]. increase induced by KCl 60mmol/ L and the peak value increased from 903 .4±369.4 to 1674. 6±563 .2 ( P < 0.05 ) . The action of elevating [ Ca2+ ]i could be blocked by 10μmol/L verapamil incompletely. The patch-clamp studies indicated that As2O3 at concentration of 10μmol/L prolonged APD50 from (263 .6±75 .2)ms to (523.9±47 .8)ms (P<0.01) and APD90 from (277.5±77.5) ms to (536.3±49.6)ms (P<0.01),and increased ICa-L from ( -6.0±1.5)pA/pF to ( -8.7±2.0)pA/pF (P < 0.01) at 0mV and also reduced IKr from (6.7±1.8)pA/pF to (4.5±1 .8)pA/pF ( P < 0.05) .However,10μmol/L verapamil could modulate prolonging APD50 from (523 . 9±47 . 8 ) ms to (340.4±83 . 8 ) ms ( P < 0.01) and APD90 from (536.3±49.6) ms to (348.9±85.5)ms (P < 0.01) and correct increasing ICa-L induced by 10μmol/L As2O3 from ( - 8 .7±2.0) pA/pF to ( - 6.6±1.4) pA/pF ( P < 0.05) at 0mV. Conclusion As2O3 could induce prolongation of the QT interval on the ECG in guinea pig hearts and the ionic mechanism is associated with increasing ICa-L and inhibiting IKr/HERG. Verapamil may be useful in normalizing QT prolongation during As2O3 therapy by decreasing ICa-L and [Ca2+]i of ventricular myocytes in guinea pig.

兰地洛尔在麻醉诱导气管插管时对Ⅱ型糖尿病患者心率变异性和QT间期的影响

目的分析兰地洛尔在麻醉诱导气管插管时对Ⅱ型糖尿病患者心率变异性和QT间期的影响。方法选取2020年8月至2022年8月我院收治的100例气管插管全麻下手术的Ⅱ型糖尿病患者为研究对象,以麻醉诱导方法差异将其分为常规组(50例,常规生理盐水进行麻醉诱导)和观察组(50例,以兰地洛尔进行麻醉诱导)。比较两组的麻醉诱导效果。结果麻醉诱导前(T0),两组的心率(HR)、血氧饱和度(SpO_(2))、平均动脉压(MAP)比较,差异无统计学意义(P>0.05);插管前即刻(T_(1))~插管后5 min(T_(4)),观察组的HR、MAP低于常规组,SpO_(2)高于常规组,差异具有统计学意义(P<0.05);在整个麻醉过程中,观察组的生命体征指标波动幅度较常规组小。T_(0),两组的低频功率(LF)、高频功率(HF)、LF/HF、总功率(TP)及QT间期比较,差异无统计学意义(P>0.05);T_(1)~T_(4),观察组的LF、LF/HF、TP及QT间期均低于常规组,差异具有统计学意义(P<0.05);T_(1)~T_(4),两组的HF比较,差异无统计学意义(P>0.05)。结论在气管插管全麻下手术的Ⅱ型糖尿病患者中,选择兰地洛尔可有效稳定患者术中生命体征,并降低术中LF、LF/TF、TP及QT间期指标,以此取得理想的麻醉诱导效果。

药源性QT间期/QTc延长和尖端扭转型室性心动过速的风险及预警措施的研究进展

许多广泛使用的药物都可能导致QT间期/QTc延长,继而引起尖端扭转型室性心动过速(torsade de pointes,TdP)等心律失常,后者可能会进一步恶化为心室颤动,甚至造成心脏性猝死。因此,为了预防和降低药源性QT间期延长和TdP的风险,对危险因素的发现、预警和纠正至关重要。近年来,临床已开始应用决策支持系统等预警策略,通过识别多种风险因素预测QT间期/QTc延长和警示TdP高风险人群。本文总结了可引起长QT间期和TdP风险的药物及相关危险因素,并归纳现有的预警措施,期望为暴露于相关风险的患者管理提供参考。

含氯法齐明化疗方案对耐多药肺结核心电图QT间期的影响及危险因素分析

目的初步探讨使用含氯法齐明的化疗方案对耐多药肺结核(multi-drug resistant pulmonary tuberculosis,MDR-TB)患者的疗效及心电图QT间期的影响,并对其危险因素进行分析,为氯法齐明临床使用的安全性提供依据。方法选取2018年1月至2020年1月河北省胸科医院收治的肺结核患者78例,按随机数字表分为常规组与氯法齐明组,各39例。观察两组治疗后的痰菌变化、病灶吸收、不良反应和QT间期,对两组QT间期延长进行单因素分析和多因素logistics回归分析。结果氯法齐明组治疗12个月后和18个月后的转阴率明显高于常规组(P<0.05);氯法齐明组治疗后复查肺部病灶的吸收率明显高于常规组(P<0.05)。但氯法齐明组中大部分患者都出现不同程度的局部皮肤发红、紫红或紫黑的色素沉着情况,而常规组无发生色素沉着情况(P<0.05)。单因素分析中,患者的性别、体重指数、耐药类型均与QT间期延长无明显相关性(P>0.05);而患者的年龄、治疗方案与QT间期延长的发生有相关性(P<0.05)。在logistics回归多因素分析中,年龄≥45岁(OR=3.931,95%CI 1.484~10.414)、治疗方案含有氯法齐明(OR=6.032,95%CI 2.738~13.288)是导致QT间期延长的独立危险因素。结论对于年龄较大的患者,使用含氯法齐明的化疗方案时,需密切监测QT间期,以防心血管事件的发生。

伊伐布雷定对慢性心力衰竭患者QT间期和心率的影响

目的探讨伊伐布雷定对慢性心力衰竭患者QT间期和窦性心律的影响。方法选择179例慢性心力衰竭患者为研究对象,行12导联同步动态心电图检查,口服伊伐布雷定30~45 d后再次复查动态心电图,比较用药前后QT间期和心率的变化。结果143例患者完成临床随访,入选本研究。口服伊伐布雷定后,所有143例患者中最大QT间期[(467.9±62.6)ms vs.(473.6±63.4)ms]、最大QTc[(489.3±56.0)ms vs.(496.6±55.4)ms]、平均QT间期[(390.5±41.1)ms vs.(398.6±43.7)ms]、平均QTc[(417.2±31.4)ms vs.(414.4±36.9)ms]、最小QTc[(377.5±36.0)ms vs.(361.3±37.0)ms]与服药前比较,差异均有统计学意义(P<0.01);最小QT间期[(348.3±42.8)ms vs.(349.6±38.9)ms]服药前后比较,差异无统计学意义(P>0.05)。最慢心率[(50.3±8.6)次/min vs.(47.7±7.8)次/min]、平均心率[(69.9±11.7)次/min vs.(64.9±10.6)次/min]和最快心率[(116.6±23.1)次/min vs.(109.0±20.1)次/min]服药前后比较,差异均有统计学意义(P<0.01)。随访期间,无室性心律失常及猝死事件发生。结论伊伐布雷定可以明显缩短最大QT间期/QTc、平均QT间期并减慢心率,其临床应用安全有效。

心电图Tp-Te/QT联合NLR预测AMI患者PCI术后心律失常

目的:分析Tp-Te/QT、NLR对AMI患者PCI术后心律失常的预测价值。方法:检测Tp-Te/QT和NLR,采用ROC曲线分析预测价值。结果:Tp-Te/QT、NLR比较,研究组高于对照组,发生组高于未发生组(P<0.05);年龄、糖尿病、Killip心功能分级、左心室射血分数、血钾、Tp-Te/QT、NLR是AMI患者术后心律失常的影响因素(P<0.05);Tp-Te/QT联合NLR预测术后心律失常的灵敏度、曲线下面积高于单独预测(P<0.05)。结论:Tp-Te/QT、NLR是AMI患者PCI术后心律失常的影响因素,有助于预测心律失常。

ICH-E14指导下QT间期测量的方法学

QT间期显著延长易导致恶性心律失常,在新药研发中应高度重视对QT间期延长的评估。ICH-E14指南作为新药研发的指导原则,以行业规范的形式规定了非抗心律失常新药上市前必须经过致QT/QTc间期延长作用的评估。这就意味着心电监测将在此类药物安全性评价中发挥重要作用。为了高标准、高质量地完成心电数据的采集与QT/QTc间期的全面分析,本文从QT间期测量时对仪器和人员的要求、测量导联的选择、QT间期起点与终点的确定、特殊情况下QT间期的测量、不同的QT间期校正方法及数据测量的注意事项等方面,对QT/QTc间期测量的方法学进行介绍。