经皮冠状动脉介入术对NSTE-ACS患者校正后QT离散度和校正后JT离散度的影响

目的探讨经皮冠状动脉介入术(PCI)治疗对非ST抬高型急性冠脉综合征(NSTE-ACS)患者心肌去极化和复极化心电参数的影响。方法研究纳入2013年于该院心内科住院病人180例,入院诊断为NSTE-ACS男118例,女62例,平均年龄(65.6±10.3)岁,住院期间均行冠状动脉造影检查并成功行球囊扩张及支架植入术。术前和术后24 h内分别行12导联体表心电图检查。测量的心电图(ECG)参数包括QRS时限、QT间期及校正后的QT间期、JT间期及校正后的JT间期,以最长QT间期与最短QT间期之差作为QT离散度,对测值行比较分析。结果对经皮冠状动脉介入术前及术后24 h内患者心电图比较发现,术前和术后24 h内患者平均QRS时限〔(0.09±0.01)s vs(0.08±0.01)s,P=0.01〕、平均校正QT离散度〔(0.09±0.04)s vs(0.06±0.04)s;P=0.001〕、平均校正后JT离散度〔(0.08±0.03)s vs(0.06±0.01)s;P=0.001〕均有显著性差异。在其他ECG参数方面二者无显著差异。结论对NSTE-ASC患者成功行经PCI治疗后,其校正后QT离散度和校正后JT离散度显著减低。     

临终患者伴发QT间期缩短的心电图分析

目的:探讨临终患者伴发QT间期缩短的心电图特征和临床意义。方法:常规测量10例临终患者的QT间期实测值(QT),通过QT间期换算公式计算QT间期预测值(QTp)、校正后QT间期值(QTc)以及QT/QTp比值。结果:10例临终患者心电图除出现各型传导阻滞、心室停搏等心电异常外,均伴随QT间期缩短(QTc<0.32～0.34s、QT/QTp<0.88)。结论:继发性QT间期缩短可能是出现于临终患者的一种罕见心电图表现,在一定程度上反映了心脏电活动衰竭,其预后不良,应引起临床高度重视。     

心电图Tp-Te间期、Tp-Te/QT比值与恶性室性心律失常的关系

目的探讨心电图T波峰末间期(Tp-Te)、Tp-Te/QT比值对恶性室性心律失常(MVA)的诊断价值。方法连续入选2017年1月1日至2018年1月1日于保定市第一中心医院西院心电图、脑电图二室行24 h 12导联动态心电图检查的患者412例为研究对象。根据是否发生恶性室性心律失常分为两组:恶性室性心律失常组72例;无恶性室性心律失常组340例。分别测定两组患者Tp-Te间期、QT间期,计算出Tp-Te间期、QTc间期及Tp-Te/QT比值,并对两组患者Tp-Te间期、QTc间期及Tp-Te/QT比值进行统计学分析。结果恶性室性心律失常组的Tp-Te间期、Tp-Te/QT比值均较非恶性室性心律失常组明显增加(P0.001)。结论 Tp-Te间期、Tp-Te/QT比值增加对于恶性室性心律失常的发生均有预测价值。     

38例脑干梗死患者临床及影像学资料分析

目的分析脑干梗死的临床及影像学特点,以提高临床诊疗水平。方法对38例脑干梗死患者的临床表现及头颅CT或磁共振成像(MRI)资料进行回顾性分析。结果大部分脑干梗死患者并无典型脑干局灶体征和症状,及时复查头颅CT或进行头颅MRI检查可确诊责任病灶。结论早期行MRI检查可明确诊断,有利于治疗方案的选择,但若无条件行MRI检查时,可于发病72h后行脑干薄层CT扫描,亦可帮助诊断。     

急性心肌梗死患者经皮冠状动脉介入治疗对心电图QT离散度的影响

为探讨经皮冠状动脉介入治疗对急性心肌梗死患者心电图QT离散度的影响及其临床意义 ,将我院资料较完整的 138例患者 ,分心肌梗死发病 6h内 (72例 )和 6h以上 (6 6例 )两组 ,测算术前和术后第 1天心电图QT间期、QT离散度、心率校正QT间期和心率校正QT离散度。结果发现 ,两组QT间期和心率校正QT间期术后与术前相比均无显著性差异 ;但术后QT离散度和心率校正QT离散度较术前显著减小 (P <0 .0 1) ,且发病 6h以内组显著小于 6h以上组 (P <0 .0 5 ) ;两组住院期间死亡率分别为 4 .2 %和 7.6 % (P =0 .394 )。结果提示 ,成功的介入治疗能显著减小心肌梗死患者的QT离散度 ,介入治疗施行得越早则减小QT离散度的效果越好。     

透析后血压变化对尿毒症患者QT间期离散度的影响

目的探讨血液透析后血压变化对尿毒症血液透析患者QT间期离散度的影响。方法选择133例行维持性血液透析治疗6个月以上病情稳定的尿毒症患者,分为透析后高血压组(55例)、低血压组(30例)和正常血压组(48例)。三组患者均给予常规治疗,血液透析频率每周3次,每次4 h。透析后分别检测三组患者的体表12导联心电图,测量并计算QT间期离散度及校正的QT间期离散度。结果高血压组与低血压组相比,QT间期离散度差异无统计学意义(P>0.05),但是校正的QT间期离散度差异具有统计学意义(P<0.01);血压正常组与非正常组相比,QT间期离散度及校正的QT间期离散度显著下降(P<0.01)。结论尿毒症维持性血液透析患者透析后高血压和低血压均能影响QT间期离散度,而高血压的影响更大。     

5018例正常受试者直线回归模型产生的QT间期校正式

先天性长QT间期综合征、电解质紊乱、应用数种抗心律失常药后、急性心肌梗塞后,QT间期的延长关系到险恶室性心律失常和心源性猝死的危险性增加。已知QT间期的时间取决于心动周期的长度,以往临床最常用Bazett在1920年提出的QT校正公式(QT_e=QT(RR)~(1/2)),但此公式在当时仅是来自对于39例年轻受试者的推导。近来人们已发现,Batett提出的QT校正公式在精确性方面存在一定的问题。本文为了评价心率对QT的影响,作者在Framingham心脏研究中心测量了5018例平均年龄44岁、无冠心病受试者的最基本心电图(男2 239例,女2779例,年龄范围28～62岁)。为按照RR周期长度而校正QT,并研究了一种直线回归模型。把受试者进一步地进行RR间距性别差异的亚分组,对照QT间期、Bazett氏校正QT间期(QT_e)和直线校正QT间期(QT_(LC)).     

头面部望诊在脑梗死发病中的预测价值研究

目的探索头面部望诊在预测及诊断脑梗死中的规律。方法通过对头面部望诊信息的采集,并与颅脑磁共振成像(MRI)检查结果相对照,进行统计分析,归纳脑梗死患者头面部望诊与颅脑MRI检查结果的相关性。结果 76例望诊有异常的患者行即刻头颅MRI检查,确诊患有脑梗死者13例;63例望诊有异常的头颅MRI阴性患者中,6个月后行头颅MRI检查,新出现脑梗死者3例;第6个月时段的60例望诊有异常的头颅MRI阴性患者中,1年后行头颅MRI检查,新出现脑梗死者5例。76例望诊有异常的患者病例纳入时及纳入1年后出现脑梗死总计21例(27.6%)。结论头面部望诊具有预测和诊断脑梗死存在的价值。     

尿流动力学检查对糖尿病患者的临床诊断价值研究

目的研究分析尿流动力学检查对糖尿病患者的临床诊断价值。方法入院病例为河北省沧州中西医结合医院2010年1月—2011年6月泌尿外科、糖尿病门诊及住院患者,共120例,将其作为研究组,经尿流动力学检查显示异常;基于此,选择同时期到院就诊治疗且经尿流动力学检查显示膀胱功能正常的100例患者作为对照组,比较两组患者尿流动力学检查结果,同时对研究组组内患者基本资料进行统计分析。结果经过比较分析,研究组和对照组各项尿流动力学检查指标比较,差异有统计学意义(P0.05)。经研究组组内患者临床资料的分析可知,男性膀胱功能受损病例明显比女性多,其中老年患者膀胱受损例数比中青年例数多,病程10年和病程10年的患者尿流动力学各指标比较差异有统计学意义(P0.05)。结论对糖尿病患者实施尿流动力学检查,可对患者膀胱功能进行合理且有效地判断,同时糖尿病膀胱功能受损多发生于男性患者、高龄患者,且病程越长,则膀胱病变的发生率也就越高,在临床中对这些类型的患者必须引起高度重视。     

儿童先天性长QT综合征患者的QT滞后现象

目的观察儿童先天性长QT综合征(LQTS)患者进行运动试验时QT间期的变化。方法因QT间期延长而行运动平板试验的患儿共33例入选本研究,按照1993年Schwartz等的LQTS诊断标准的计分分值分为两组:LQTS组:总计分值为4分及以上的患者17例,男13例、女4例,年龄11.6±3.7岁;可疑组:评分为1.5~3.5分的患者16例,男9例、女7例,年龄13.8±4.2岁。另选行运动试验的18例正常儿童作为对照组,男11例、女7例,年龄12.4±3.1岁。记录整个运动试验中和恢复期的心电图,观察QT间期和心率的变化,记录并计算恢复期第1,2,4,6 m in QT间期与运动过程中同心率时QT间期的差值(ΔQT)。结果三组患者在运动中随着心率的增加,QT间期逐渐缩短。运动恢复期,随着心率的减慢,三组的QT间期也逐渐延长,但LQTS组恢复期QT间期却显著短于运动过程中处于同心率时的QT间期。LQTS组在恢复期1,2,4 m in的ΔQT值均显著大于其它两组(P均<0.05)。LQTS组在QT间期与心动周期的关系图上呈现明显的“QT滞后环”。结论儿童LQTS患者运动试验恢复期与运动过程中相比,QT间期的变化明显滞后于心率的变化。     

Miocardiopatia hipocalcémica

The association between hypocalcemia and heart failure is rare. There are few reported cases in the literature of this association, which is termed hypocalcemic cardiomyopathy.We report the case of a 61-year-old woman with no relevant medical history, admitted for progressively worsening exertional dyspnea, orthopnea and edema of the lower limbs for a previous month. Physical examination showed diffuse muscle spasms, with no signs of latent tetany.Further investigation revealed ionized calcium 0.54 mmol/l (normal 1.12-1.30), phosphorus 9.8 mg/dl, parathyroid hormone <2.5 pg/ml and CK >3000 U/l, with normal thyroid function. The electrocardiogram showed long QT interval and a pattern of left ventricular overload, and myocardial biomarkers were negative. The echocardiogram revealed regional wall motion abnormalities, coronary angiography was normal and a cranial CT scan detected calcification of basal ganglia and white matter.She started diuretic and calcium replacement therapy which resulted in complete clinical recovery, with no need for heart failure therapy after normalization of serum calcium.     

Distribution and prognostic significance of QT intervals in the lowest half centile in 12,012 apparently healthy persons

The presence of an abnormally short QT interval has been noted among survivors of idiopathic ventricular fibrillation and among close relatives of victims of unexplained sudden death. Most reported cases have had rate-corrected QT (QTc) intervals of <300 ms. The prevalence of such values in the community has not been documented. We reviewed the electrocardiograms (ECGs) of 12,012 subjects who underwent routine medical examinations for occupational reasons. The QT interval was measured by 2 physicians in all cases, and QTc interval was calculated. All ECGs with QTc values in the lowest 5% were reviewed by 2 cardiologists expert in QT analysis, and the QT measurement was corrected if necessary. Information about subsequent survival was obtained from the case file or from public records. In the lowest 1/2 centile, the distribution of QTc values continued to follow a normal pattern without evidence of a distinct subpopulation of low values. The shortest QTc encountered was 335 ms. Information about subsequent survival was available for 36 of the 60 subjects with the lowest 1/2 centile of QTc values. None of these subjects died during the 7.9 +/- 4.5 years subsequent to the ECG that demonstrated the short QT interval. In conclusion, a QTc interval of 相似文献   

QT interval and dispersion among emergency medical responders in Mansoura city

BackgroundOccupational factors are likely to contribute to increased cardiovascular disease risk among emergency medical responders (EMR). The aim of this study was to clarify whether EMR stressful Job and their prolonged exposure to work stress are associated with an increase in QT interval and QT dispersion.MethodsA comparative cross sectional study was conducted upon 137 EMR and a 119 matched control group composed of non-emergency workers. All study population were subjected to history taking for age, risk factors such as diabetes mellitus, hypertension, and smoking, history of cardiovascular disease, and the use of medications. Measurement of blood pressure, and body mass index (BMI) was recorded. Standard 12-lead ECGs were recorded for the analysis of heart rate (HR), QT, QTc, QT dispersion, T_peak and T_end (Tpe), and Tpe dispersion. In addition the levels of epinephrine and nor-epinephrine hormones in urine during the work shift were analyzed.ResultsHigh risk EMR had a significant increase in blood pressure, urinary epinephrine and norepinephrine compared to the control group (p < 0.05). There were no differences between studied groups as regards heart rate, QT, QTc, QT dispersion, QTc dispersion, Tpe interval, and Tpe dispersion with no significant correlation between catecholamine levels and QTc interval.ConclusionQTc and dispersion were not increased among emergency medical responders in spite of having higher catecholamine levels.     

Clinical investigation on the patients with tachyarrhythmic syncope with special reference to comparative study between long QT syndrome and ventricular tachycardia without long QT interval

The long QT syndrome (LQTS) is one of the important diseases that may lead to sudden death mainly in childhood, however etiology and pathogenesis are still poorly understood. The group studied consisted of 6 patients with a history of ventricular tachyarrhythmic syncope, 3 with long QT syndrome (LQTS) and 3 without long QT interval, and of 4 patients with ventricular tachycardia without syncopal episode. Their ages ranged from 5 years to 17 years. Histopathology of endomyocardial biopsy was nonspecific and mild in two cases but in one patient with LQTS, who had several episodes of syncope and refractory ventricular arrhythmia, remarkable subendocardial fibrosis, interstitial fibrosis and hypertrophy of myocytes were demonstrated. As far as ventricular tachycardia without long QT interval was concerned, in the patients with VT with syncope, histopathological abnormalities were more remarkable than in those without syncope. Electrophysiological findings in the patients with LQTS showed no characteristic findings, but only mild abnormalities with functional atrioventricular conduction disturbance on programmed atrial pacing. No inducible VT was demonstrated. Although electrophysiologic study and endomyocardial biopsy are of limited value, such studies are considered to be worthwhile for treating ventricular arrhythmias, and making a prognosis of the patients with tachyarrhythmic syncope and LQTS.     

The effect of electroconvulsive therapy on QT dispersion

Electroconvulsive therapy (ECT) is used frequently in psychiatric practice and various electrocardiographic (ECG) changes have been described during ECT. QT dispersion (defined as maximal QT interval minus minimal QT interval) as assessed on the surface electrocardiogram has been demonstrated to reflect regional inhomogeneity of ventricular repolarization. The aim of this study is to examine the effect of electroconvulsive therapy on QT dispersion. We studied 27 patients (age range 24-42 y, mean age 34 y, 11 men) without heart disease who were treated with ECT. Structural heart disease was eliminated with routine clinical examination and laboratory tests, echocardiography, and exercise treadmill test. QT interval and corrected QT (QTc) dispersion was measured on a 12-lead ECG before and just after ECT. QTc dispersion increased from 28.9 +/- 7.4 ms at baseline to 81.4 +/- 12.8 ms after the procedure (P < 0.0001). This result demonstrated that QTc dispersion increased significantly during ECT. This finding may explain that increased inhomogeneity of ventricular repolarization is associated with enhanced vulnerability to arrhythmias during ECT.     

Molecular and clinical determinants of drug-induced long QT syndrome: an iatrogenic channelopathy

More than 70 drugs present on the Swiss market can cause drug-induced long QT syndrome (LQTS), which is associated with torsades de pointes (TdP) arrhythmias, potentially leading to sudden cardiac death. Basic and clinical investigations performed during the last decade have helped a better understanding of the mechanisms and risk factors of this serious public health problem. In their vast majority, QT interval prolonging drugs block the human ERG (hERG) channel involved in the repolarisation phase of the cardiac action potential, and thus lengthen the QT interval. Beside the well-known QT interval prolonging action of class IA, IC and III anti-arrhythmic drugs, many antibiotics, neurotropic, antifungal, and antimalarial drugs are also able to cause drug-induced LQTS. Reviewing the literature indicates that the risk of QT interval prolongation and TdP is increased in females, in patients with organic heart diseases and hypokalaemia. Furthermore in a few cases, genetic factors have also been reported. However thus far, no genetic test is available to detect at-risk patients, and in consequence, drug prescribers are still relying only on the clinical history and findings to perform an evaluation of the risk. Treatment of drug-induced LQTS and TdP includes identifying and withdrawing the culprit drug(s), infusing magnesium and, in resistant cases acceleration of the heart rate. In this review article we provide a list of QT interval prolonging drugs adapted to the pharmaceuticals found on the Swiss market that can be used as a check-list for drug prescribers and at-risk patients.     

Prenatal findings in patients with prolonged QT interval in the neonatal period.

OBJECTIVE: To describe prenatal abnormalities of cardiac rhythm in patients with prolonged QT interval in the neonatal period. DESIGN: A retrospective analysis of the results of fetal echocardiography and the outcome in patients with prolonged QT interval in the neonatal period who had been referred for prenatal evaluation. SETTING: Two university hospitals. PATIENTS: Nine patients with prolonged QT interval in the neonatal period who had been referred for prenatal evaluation. Fetal echocardiograms were obtained from 24 to 40 weeks of gestation. Indications were fetal bradycardia (five patients), a family history of long QT syndrome (two patients), and complex arrhythmias (two patients). RESULTS: Seven fetuses had persistent sinus bradycardia without ventricular arrhythmias (heart rates 70-120 beats/ min). Five patients were treated with propranolol, after the diagnosis had been established by postnatal electrocardiogram (ECG). One of these patients died suddenly at the age of 3 weeks, after the treatment had been stopped because of profound bradycardia. One of the remaining two patients who did not receive propranolol had a syncope at the age of 6 weeks. Two fetuses presented with frequent runs of ventricular tachycardia and intermittent bradycardia caused by intermittent, functional second degree atrioventricular block. Both patients died on the first day of life despite treatment with propranolol and transvenous temporary pacing. CONCLUSIONS: Sinus bradycardia in an otherwise normal fetus may be a symptom of long QT syndrome. Postnatal ECGs and a family examination are strongly recommended in these children. In fetuses with frequent runs of ventricular tachycardia and intermittent second degree atrioventricular block long QT syndrome should be suspected prenatally. These high risk patients should be delivered in centres with a paediatric cardiology unit.     

Präventives Ganzkörperscreening unter Einbeziehung moderner Bildgebung mit Hilfe der Magnetresonanztomographie

BACKGROUND: With respect to the prognosis of the population and costs, the focus of the health-care system should lie more on preventive medicine in the future. The value of screening examinations as secondary prevention is, however, controversial, as only few investigations exist. PATIENTS AND METHODS: The authors report on 1,007 consecutive patients who underwent a screening examination based on clinical examinations and whole-body magnetic resonance imaging (MRI) of the brain, arterial system, heart and abdomen in a private outpatient center. Clinical examinations consisted of physical examination, ECG, stress ECG, lung function test, ultrasound of carotid vessels and thyroid, blood and urinary tests. Besides clinical tests, all patients were studied by routine MRI of the brain, the heart (exclusive of the coronary system) and whole-body MR angiography. In the same setting, 855 of the patients (855/1,007) underwent an MR colonoscopy in dark-lumen technique, and the remaining 152 of the patients (152/1,007) an abdominal MR overview (T(1) Vibe). Patients with MR colonography obtained triple-dose gadolinium-BOPTA. RESULTS: Screening was performed in 1,007 patients, 71% were men and 29% women. Altogether, 895 relevant findings were reported in 1,007 patients. 24% of the findings were detected exclusively by MRI. Most of the MR-based diagnoses were cardiovascular in nature, including 29 silent myocardial infarctions (3.2%), 27 aortic aneurysms (3%), two of them being > 5 cm in diameter, eleven intracranial extraaxial tumors (1.2%), 75 colonic polyps (8.4%), four neoplastic tumors (0.44%; three renal cell carcinomas, one bronchial carcinoma), and two cerebral aneurysms (0.22%). The MRI results of two colonic polyps were false-positive. CONCLUSION: Whole-body screening reveals a number of therapeutically relevant diagnoses, primarily of cardiovascular origin. MRI yields valuable additional diagnoses that have a significant impact on the further medical strategy. The value of the screening examination lies mainly in the experienced interpretation of both radiologic and clinical tests and the integration into an overall medical concept and clinical management.     

The association between SCN5A, KCNQ1 and KCNE1 gene polymorphisms and complex ventricular arrhythmias in survivors of myocardial infarction

BACKGROUND: Post-MI patients are highly susceptible to sudden cardiac arrest (SCA) and sudden cardiac death (SCD) resulting from ventricular arrhythmia (VA). The search for new clinical predictors to identify those patients who are at the highest risk of these events is therefore essential. Numerous data indicate that the presence of polymorphisms and mutations in the cardiac ion channel genes SCN5A, KCNQ1 and KCNE1 might serve as such a predictor. Since genetic alterations in these genes underlie congenital long QT syndrome (LQTS), which is associated with an increased occurrence of arrhythmic complications and SCD, we decided to verify how alterations in these genes contribute to QT interval abnormalities and consequently to VA, SCA and SCD in post-MI patients. AIM: To detect single nucleotide polymorphisms (SNP) in SCN5A, KCNQ1 and KCNE1 of post-MI patients, and to assess whether they are related to electrophysiological markers of cardiac arrhythmia (QT interval) and the clinical course. METHOD: The study group consisted of 100 patients (27 females, mean age 69 years) with documented MI 3 months before enrolment. All patients underwent baseline and (after 12 months) control examinations encompassing history, physical examination, basic laboratory analysis, resting 12-lead ECG, 24-hour 12-lead Holter ECG monitoring and echocardiography. Genetic tests were performed during baseline examination. RESULTS: In post-MI patients two exonic polymorphisms, H558R in SCN5A and S38G in KCNE1, and two intronic ones, in KCNQ1, were detected. H558R was associated with an increase in QT dispersion (QTd) at minimum and maximum heart rate and QT interval prolongation before premature ventricular beats (PVB), whereas S38G and intronic polymorphisms were related to an increase in QTd before PVB. None of the above polymorphisms was related to complex VA, SCA or SCD. CONCLUSION: The above polymorphisms were associated with abnormal repolarisation phase patterns in post-MI patients, which manifested in QT interval prolongation and QTd increase. There was no relationship between these polymorphisms and complex VA, SCA or SCD. The results show that not only exonic alterations but also intronic ones may affect the phenotype.     

Evidence for a cardiac ion channel mutation underlying drug-induced QT prolongation and life-threatening arrhythmias

The aim of this study was to test the hypothesis that some cases of drug-induced arrhythmias depend on genetic predisposition. Excessive prolongation of the QT interval and life-threatening arrhythmias (torsades de pointes or ventricular fibrillation) may occur in response to a variety of cardiac and noncardiac drugs, with detrimental effects on patient safety and the investments made by the pharmaceutical industry. Moss and Schwartz hypothesized that some drug-induced arrhythmias might represent cases of "forme fruste" of the congenital long QT syndrome (LQTS). The availability of molecular screening techniques for LQTS genes allowed us to test this hypothesis. An elderly female patient with documented cardiac arrest related to cisapride, a prokynetic drug that blocks I(Kr), and transiently prolonged QT interval underwent mutational analysis of the known LQTS-related genes performed by single-strand conformational polymorphism and DNA sequencing. Double-electrode voltage clamp in Xenopus oocytes as the expression system was used to study the in vitro cellular phenotype caused by the genetic defect in coexpression with the wild-type (WT) gene. Molecular analysis revealed a heterozygous mutation leading to substitution of a highly conserved amino acid in the pore region of KvLQT1. This mutation was present not only in the patient with ventricular fibrillation but also in her two adult asymptomatic sons who have a normal QT interval. In vitro expression of the mutated KvLQT1 protein showed a severe loss of current with a dominant negative effect on the WT-KvLQT1 channel. Our findings demonstrate that some cases of drug-induced QT prolongation may depend on a genetic substrate. Molecular screening may allow identification among family members of gene carriers potentially at risk if treated with I(Kr) blockers. Evolving technology may lead to rapid screening for mutations of candidate genes that cause drug-induced life-threatening arrhythmias and allow early identification of individuals at risk.