Do Different TSH Suppression Levels Effect Heart Rate Variability and QT Dispersions in Patients with Differentiated Thyroid Cancer?

OBJECTIVE: The aim of this study was to investigate changes in heart rate variability (HRV) and QT dispersion (QTd) in patients with differentiated thyroid cancer at different TSH suppression levels. METHODS: The study included 125 DTC patients, who had been on TSH suppression treatment (TSHST) for at least 1 year. The patients were categorized into three groups: patients with TSH < 0.1 mIU/L (n:30), those with TSH 0.1 to 0.5 mIU/L (n:56), and those with TSH 0.5 to 2 mIU/L (n:39). The first two groups were classified as suppression groups, and the last as replacement (control) group. All patients underwent 12-lead electrocardiogram (ECG) recording and 24-hour rhythm holter echocardiography analysis. RESULTS: The HRV results derived from a 24-hour rhythm holter did not exhibit any significant difference (p < 0.05). In dispersion evaluations, the QTd was significantly longer in the suppression groups (groups 1 and 2), than in the replacement group (group 3) (p < 0.001 and p:0.002, respectively). The same was found for corrected QT dispersion (QTcd) (p < 0.001 and p: 0.008, respectively). In multivariate linear regression analysis, TSH was found to affect QTd (ß = -0.299; p = 0.002) and QTcd (ß = -0.300; p = 0.002) values independently. CONCLUSION: In this study, it was shown that in patients with DTC receiving TSHST, QT dispersion prolonged as the TSH suppression level increased. Especially in high-risk DTC patients, evaluation of QTd may be useful in terms of evaluating cardiovascular risk and regulating TSHST level.

Evaluation of cardiac functions in children with familial Mediterranean fever.

OBJECTIVES: Familial Mediterranean fever is an autosomal recessive autoinflammatory inherited disease. We aimed to evaluate cardiac involvement in children with familial Mediterranean fever during the attack-free period. MATERIAL AND METHODS: The prospective study included 75 familial Mediterranean fever patients during the attack-free period and 50 healthy children. Cardiac evaluation was performed using electrocardiography, 24-hour ambulatory Holter monitoring, and conventional and tissue Doppler echocardiography. Aortic stiffness indices were calculated. RESULTS: There were no differences between the groups in age, height, sex, body mass index, and arterial blood pressure parameters (p > 0.05). QT and corrected QT dispersion parameters were similar in both groups (p > 0.05). The E wave velocity and the E/A ratio of the mitral and tricuspid valves decreased, and the A wave velocity of the tricuspid and mitral valve increased in familial Mediterranean fever by the Doppler echocardiography (p < 0.05). The myocardial contraction velocities (Sd), early relaxation velocity (Ed), and Ed/late relaxation velocity (Ad) of both ventricles were decreased in familial Mediterranean fever group, whereas the Ad of both ventricles and the interventricular septum was increased in familial Mediterranean fever group. Aortic strain and distensibility were decreased, and pressure strain elastic modules (Ep), pressure strain normalised (Ep*) by diastolic pressure, and aortic stiffness ß index were increased in familial Mediterranean fever patients (p < 0.05). When time domain heart rate variability parameters were evaluated, SDNN-i, RMSSD, and PNN50 significantly decreased in familial Mediterranean fever patients (p < 0.05), whereas SDNN and SDANN were similar in both groups (p > 0.05). CONCLUSION: Our findings showed that cardiac involvement could exist in familial Mediterranean fever patients, even during nonattack periods.

Relationship between Alzheimer dementia and QT interval: A meta-analysis.

While the link between aging and mortality from dementia is widely appreciated, the mechanism is not clear. The objective of this study was to determine whether there is a direct relationship between Alzheimer dementia (AD) and the QT interval, because the latter has been related to cardiac mortality. A systematic review and meta-analysis were conducted after a Medline and EMBASE search using terms "Alzheimer disease or Dementia AND QT interval, QT dispersion or cardiac repolarization." Four studies with control groups were identified. There were significant differences in QT interval between individuals with AD vs individuals without dementia (controls) (odds ratio (OR)1.665 [random effects model] and 1.879 [fixed effect model]) (p < 0.001). There were significant differences in QT interval between individuals with AD vs individuals with mild cognitive impairment (MCI) (OR 1.760 [random effects] and 1.810 [fixed effect]) (p < 0.001). A significant (p <0.001) correlation exists between the QTc and the Mini-Mental State Exam (MMSE), a test of cognitive function. Two studies examined QT variability (the difference between the longest and shortest QT interval on a 12 lead ECG); the OR for QT variability AD vs MCI was 3.858 [random effects model] and 3.712 [fixed effects model] (p < 0.001). When compared to the control group, the OR for QT dispersion in AD was 6.358 [random effects model] or 5.143 ( P< 0.001) [fixed effects model]. A qualitative analysis of the data raised questions about paucity of data defining the nature of the control groups, the pathophysiologic mechanism, and the uniform use of a poor QT heart rate correction factor. The longer QT in AD, greater QT variability in AD, and the direct relationship between QT interval and AD severity supports a brain-heart connection in AD that might be fundamental to aging-induced AD and mortality. Issues with defining the control group, limited number of studies, conflicting data in population studies, and the lack of a strong electrophysiological basis underscore the need for additional research in this field.

Defective recovery of QT dispersion due to no-reflow following acute interventional therapy in patients with ST-segment elevation myocardial infarction.

Background: Previous studies have suggested that adequate myocardial reperfusion after percutaneous coronary intervention (PCI) can improve the inhomogeneity of myocardial repolarization. However, it remains unclear whether no-reflow (NR) following emergency PCI involves disadvantages related to ventricular repolarization indices. The present study aimed to determine the effect of NR on QT dispersion (QTd) in patients with ST-segment elevation myocardial infarction (STEMI) and to evaluate the prognostic value of the relative reduction of QTd on ventricular arrhythmia events (VAEs). Methods: A prospective case-control study was conducted. According to the inclusion criteria, 275 patients with STEMI who underwent primary PCI treatment at the First People's Hospital of Anqing affiliated to Anhui Medical University from January 2020 to May 2023 were enrolled. According to whether NR occurred during PCI, these patients were divided into two groups: an NR group and a non-NR group. Subsequently, the QT intervals were measured before and at 12 hours after PCI. Afterward, the QTd, corrected QTd (QTcd), and the relative reduction of QTd and QTcd 12 hours pre- and postprocedure (ΔQTd-R and ΔQTcd-R, respectively) were calculated. Finally, multivariable logistic regression analysis was performed to predict the risk of VAE occurrence. Results: In the non-NR group, there was a significant decrease from baseline in postprocedure QTd (48±17 vs. 73±22 ms; P=0.009) and QTcd (54±19 vs. 80±23 ms; P=0.01); in contrast, the NR group showed no significant difference in QTd (64±20 vs. 75±23 ms; P=0.58) or QTd (70±22 vs. 82±26 ms; P=0.45). Furthermore, the ΔQTd-R and ΔQTcd-R were both lower in the NR group than in the non-NR group (P<0.05); however, the rate of VAEs was higher in the NR group than in the non-NR group (15.2% vs. 6.2%; P=0.02). The multivariable logistic regression analysis results revealed that each increase of 12% in ΔQTcd-R was an independent predictor of VAEs (odds ratio: 0.547; 95% confidence interval: 0.228-0.976). Conclusions: The NR phenomenon following primary PCI in patients with STEMI leads to the defective recovery of QTd and QTcd. Furthermore, ΔQTcd-R can be viewed as an effective indicator for evaluating the myocardial repolarization inhomogeneity, and short-term clinical outcomes.

The relationship between vitamin B12 levels and electrocardiographic ventricular repolarization markers / La relación entre los niveles de vitamina B12 y los marcadores electrocardiográficos de repolarización ventricular

Background: it has been shown that vitamin B12 deficiency, which can cause hematological and neuropsychiatric disorders, may also be associated with cardiac autonomic dysfunction, heart rate variability, endothelial dysfunction, and a decrease in myocardial deformation. Aims: the aim of our study is to evaluate the relationship between vitamin B12 levels and electrocardiographic repolarization disorders, which are indicators of arrhythmogenic predisposition in healthy individuals. Methods: our study population consisted of 214 healthy adults. Considering the distribution of vitamin B12 levels and accepting 25 % and 75 % percentiles as the cut-off values, the participants were divided into 3 groups. Laboratory, echocardiography and electrocardiography (ECG) measurements were compared between three groups. ECG measurements were performed manually and Tpeak-Tend (Tp-e), Tp-e corrected (Tp-ec), QT and QT corrected (QTc) intervals were calculated. Results: the patients in Group 1 (vitamin B12 < 253 pg/ml) were found to have significantly higher QT and QTc dispersions, Tp-e interval, Tp-e/QT and Tp-e/QTc ratios when compared to those in Group 2 (253 pg/ml < vitamin B12 > 436 pg/ml) and Group 3 (vitamin B12 > 436 pg/ml). On the other hand, a negative significant correlation was detected between vitamin B12 levels and Tp-e, Tp-e/QT, Tp-e/QTc ratios, QT and QTc dispersions. Conclusion: a low level of vitamin B12 in healthy individuals can be a significant indicator of arrhythmogenic susceptibility. A close follow-up of these subjects in terms of arrhythmogenic predisposition can be useful (AU)

Fundamento: se ha demostrado que la deficiencia de vitamina B12, que puede causar trastornos hematológicos y neuropsiquiátricos, también puede estar asociada con disfunción autonómica cardíaca, variabilidad de la frecuencia cardíaca, disfunción endotelial y disminución de la deformación miocárdica. Objetivos: el objetivo de nuestro estudio es evaluar la relación entre los niveles de vitamina B12 y los trastornos de repolarización electrocardiográfica que son indicadores de predisposición arritmogénica en individuos sanos. Métodos: la población del estudio fue de 214 adultos sanos. Considerando la distribución de los niveles de vitamina B12 y aceptando los percentiles del 25 % y 75 % como valores de corte, los participantes se dividieron en 3 grupos. Se compararon las mediciones de laboratorio, ecocardiografía y electrocardiografía (ECG) entre tres grupos. Las mediciones del ECG se realizaron manualmente y se calcularon los intervalos Tpeak-Tend (Tp-e), Tp-e corregido (Tp-ec), QT y QT corregido (QTc). Resultados: se encontró que los pacientes del grupo 1 (vitamina B12 < 253 pg/ml) tenían dispersiones QT y QTc, intervalo Tp-e, cocientes Tp-e/QT y Tp-e/QTc significativamente más altos cuando se compararon con los del grupo 2 (253 pg/ml < vitamina B12 > 436 pg/ml) y el grupo 3 (vitamina B12 > 436 pg/ml). Por otro lado, se detectó una correlación significativa negativa entre los niveles de vitamina B12 y las relaciones Tp-e, Tp-e/QT, Tp-e/QTc, dispersiones QT y QTc.Conclusión: el bajo nivel de vitamina B12 en los individuos sanos puede ser un indicador significativo de susceptibilidad arritmogénica. Un seguimiento estrecho de estos sujetos en términos de predisposición arritmogénica podría ser útil (AU)

Application of two indexes in the evaluation of carbon monoxide toxic heart disease / 中华急诊医学杂志

Objectives:To investigate the relationship between heart rate adjusted QT dispersion (QTcd) and soluble growth stimulating gene 2 protein (sST2) and the severity and prognosis of patients with acute carbon monoxide toxic heart disease.Methods:Retrospective analysis was performed on 135 patients with acute carbon monoxide toxic heart disease admitted to the Emergency Medical Department of our hospital from January 2017 to 2020. Blood sST2, creatine kinase isoenzyme (CK-MB) and troponin I(cTnI) concentrations were recorded at 3 h, 12 h, 2 d and 3 d immediately after admission.The patient was measured and calculated on the day of admission,2 d,3 d and QTcd at discharge.According to the toxicity of carbon monoxide in heart disease severity was divided into mild heart disease group (58 cases), moderate heart disease group (45 cases), severe heart disease group (32 cases), according to whether severe heart disease were divided into severe group (32 cases) and non severe group (103 cases), according to whether the patients death in patients with severe heart disease.Results:Thirty-two of the 135 patients had severe toxic heart disease, with an incidence of 23.7%.In the severe group, sST2, cTnI and CK-MB increased from 24 h and 2 d after admission, and the detected values were all higher than those of the non-severe group and the normal control group, with statistically significant differences ( P<0.05).Before treatment, there were statistically significant differences in sST2 and QTcd between the toxic group and the non-severe group and the normal control group ( P<0.05).After 2 d and 3 d poisoning, there were statistically significant differences between the two groups ( P<0.05). ROC curve analysis showed that the area under the sST2 curve was 0.726, 95% CI was 0.555-0.898, sensitivity was 56.3%, specificity was 94.1%, and truncation was 88.5 ng/mL.The area under the QTcd curve was 0.745, 95% CI was 0.602-0.889, sensitivity was 56.3%, specificity was 82.4%, and truncation value was 68.5 ms.The area under the combined detection curve was 0.939, 95% CI was 0.874-1.000, sensitivity was 81.3%, specificity was 91.2%. Conclusions:In patients with acute carbon monoxide toxic heart disease, the level of sST2 increased earlier than THAT of cTnI and CK-MB, and the combined observation of sST2 and QTcd can be used as an indicator for early prediction of acute carbon monoxide toxic heart disease and its severity.

Effects of lidocaine oropharyngeal spray applied before endotracheal intubation on qt dispersion in patients undergoing coronary artery bypass grafting: a prospective randomized controlled study

Abstract Objective: To investigate the effects of lidocaine oropharyngeal spray applied before endotracheal intubation on hemodynamic responses and electrocardiographic parameters in patients undergoing coronary artery bypass grafting. Methods: A total of 60 patients who underwent coronary artery bypass grafting surgery were included in this prospective randomized controlled study. Patients were randomly divided into two groups, the topical lidocaine group (administration of 10% lidocaine oropharyngeal spray, five minutes before laryngoscopy and endotracheal intubation) and the control group. Both groups were compared with each other in terms of main hemodynamic parameters including mean arterial pressure and heart rate, as well as P and QT wave dispersion durations, before and after endotracheal intubation. Results: The groups were similar in terms of age, gender, and other demographics and basic clinical characteristics. There was a statistically significant difference between the groups in terms of QT dispersion durations after laryngoscopy and endotracheal intubation. The increase in QT dispersion duration was not statistically significant in the topical lidocaine group, whereas the increase in QT dispersion duration was statistically significant in the control group. When the groups were compared in terms of P wave dispersion durations, there were significant decreases in both groups, but there was no significant difference between the groups. Conclusion: Our study revealed that the topical lidocaine administration before endotracheal intubation prevented increase of QT dispersion duration in patients undergoing coronary artery bypass grafting. Trial Registration: NCT03304431

QT Interval Dispersion Behavior in Patients With and Without Obstructive Coronary Artery Disease Undergoing Exercise Test

Abstract Background: Stress test is used to detect coronary artery disease (CAD). The QTc interval dispersion (dQTc) is an electrocardiographic index of ventricular repolarization heterogeneity. Some researchers have linked transient myocardial ischemia induced by physical exertion with increased heterogeneity of ventricular repolarization measured by dQTc. Objectives: To study the patterns of dQT in patients with and without chronic obstructive CAD and to define a reliable cutoff point for dQT that could become a diagnostic criterion for myocardial ischemia. Methods: We retrospectively analyzed the electrocardiogram in resting and in exercise of 63 patients submitted to exercise test and cardiac catheterization. We divided the patients into three groups: true negative (VN), true positive (VP) and false positive (FP). VN: patients with coronary lesion lower than 70% and exercise test without myocardial ischemia; VP: individuals with stenosis greater than 70% in coronary arteries and a test suggestive of myocardial ischemia; FP: people with stenosis lower than 70% in the coronary arteries and stress test with ischemia criteria. Values of p < 0.05 were considered statistically significant. Results: Resting dQTc was not different among the three groups. However, for the dispersion of the QTc interval in exercise was, respectively, 47 ± 17 ms, 72 ± 42 ms, and 61 ± 31 ms for VN, VP and FP (p = 0.003). Conclusions: Obstructive chronic coronary disease patients have an increase in dQTc during exercise. Measurement of dQTc may be helpful in the diagnosis of myocardial ischemia in the stress test.

An easy and reliable way to prevent electrocardiographic deteriorations of patients undergoing off-pump coronary artery bypass surgery: preoperative anxiolytic treatment

Abstract Objective: To investigate the effects of preoperative anxiety relieving on electrophysiological changes in patients undergoing off-pump coronary artery bypass surgery. Methods: A total of 61 patients at ASA III risk group in the age range of 18-65 years were enrolled in the present study. Patients were randomly divided into two groups. Group S (Sedation group) was administered 0.04 mg/kg lorazepam per os (PO) twice before the operation. Group C (control group) was not administered with any anxiolytic premedication. State Trait Anxiety Inventory (STAI-I) and Beck Anxiety Inventory (BAI) were used to evaluate the level of anxiety. Electrocardiography (ECG), pulse oximeter and standard monitoring were performed for each patient. QT and P dispersions in each derivation of all ECGs were calculated. Results: Preoperative STAI-I scores were significantly lower in sedation group compared to the controls. Mean values of QT dispersion measured before induction, at the 1st minute of induction, 30th second of intubation and 4th minute of intubation in sedation group were significantly reduced compared to controls (P=0.024; P=0.027; P=0.001; P=0.033, respectively). The mean values of P dispersion measured before induction, at the 3rd minute of induction, 30th second of intubation and 4th minute of intubation in sedation group were significantly reduced compared to controls (P=0.001; P=0.020; P=0.023; P=0.005, respectively). Conclusion: Elevated anxiety levels in patients undergoing coronary bypass surgery have a negative effect through prolonged QT and P-wave dispersion times. Anxiolytic treatment before surgery may be useful to prevent ventricular and atrial arrhythmias and associated complications through decreasing the QT and P-wave dispersion duration.

The effect of Huoxue-Yixin decoction combined with atorvastatin on NT-pro and QTd in patients with chronic heart failure / 国际中医中药杂志

Objective To observe the effect of Huoxue-Yixin decoction combined with atorvastatin on NT-pro and QTd in patients with chronic heart failure (CHF). Methods A total of 120 patients with chronic heart failure in our hospital from December 2016 to June 2017 were enrolled in this study. The subjects were randomly divided into the control group (n=60) and the treatment group (n=60). The control group were treated with conventional treatment,and the treatment group were treated with Huoxue-Yixin decoction combined with atorvastatin. The two groups were treated for 30 days. The NT-ProBNP, QTd, QTcd and LVESD, LVEDD, LVEF of the two groups before and after treatment were compared.Results The QTd at 2 d(45.6 ± 8.9 ms vs.64.0 ± 18.2 ms,t=-7.029),14 d(44.3 ± 6.8 ms vs.55.7 ± 12.8 ms,t=-6.092)in the experiment group were significantly lower than those of control group(P<0.01).The level of QTcd at 2 d(50.8 ± 10.1 ms vs.71.2 ± 19.8 ms,t=7.109), 14 d(48.1 ± 9.7 ms vs.63.1 ± 13.1 ms,t=7.128)of the experiment group were significantly lower than those of control group(P<0.01).After treatment,the NT-ProBNP(494.58 ± 331.61 ng/L vs.594.71 ± 382.65 ng/L,t=-1.532), LVESD(40.23 ± 3.13 mm vs.49.72 ± 3.99 mm,t=-14.495)and LVEDD(58.22 ± 3.30 mm vs.65.11 ± 3.95 mm, t=-10.720)of the treatment group were significantly lower than those of the control group(P<0.01).The LVEF (69.82% ± 4.72% vs. 50.34% ± 4.02%, t=-10.720) of the treatment group was significantly higher than the control group(P<0.01).Conclusions The Huoxue-Yixin decoction combined with atorvastatin can reduce the level of NT-ProBNP, QTd and QTcd in patients with CHF, can significantly improve cardiac function.

Changes of QT Dispersion in Hemodialysis Patients after Administrating Zhigancao Decoction () / 中国结合医学杂志

<p><b>OBJECTIVE</b>To observe the alteration of QT dispersion (QTd) and QTc dispersion (QTcd) in hemodialysis patients after oral administration of Zhigancao Decoction (, Roasted Licorice Decoction, RLD).</p><p><b>METHODS</b>To investigate the alteration of QTd and QTcd in 68 routine hemodialysis patients before and after hemodialysis with 12-lead electrocardiogram (ECG) after orally administrated RLD for 4 weeks. Blood was also taken for measurement of plasma electrolytes, liver function, renal function, hemoglobin (Hgb) and hematocrit (HCT).</p><p><b>RESULTS</b>After hemodialysis, QTd and QTcd were prolonged evidently; the difference was significant between before and after hemodialysis (P<0.05). After RLD orally administrated for 4 weeks, QTd and QTcd only slightly increased after dialysis compared with pre-dialysis (P>0.05). The QTd and QTcd of the post-therapy-post-dialysis decreased significantly compared with the pre-therapy-post-dialysis (P<0.05). There were no other significant changes in other variables (post-therapy-pre-dialysis vs. pre-therapy-pre-dialysis, or post-therapy-post-dialysis vs. pre-therapy-post-dialysis;P>0.05). After therapy, the number of patients with supraventricular arrhythmia, occasional ventricular premature beat and multiple ventricular premature beat were decreased from 15 to 4, 10 to 2 and 7 to 1, respectively.</p><p><b>CONCLUSION</b>RLD therapy not only lowered the increased QTd and QTcd after hemodialysis, but also displayed a safety profile.</p>

Effect of different anti -platelet therapies on QT dispersion in patients with acute coronary syndrome after percutaneous coronary intervention / 中国基层医药

Objective To investigate the effect of anti -platelet therapy on QT dispersion(Qtd,QTcd)in patients with acute coronary syndrome(ACS)after percutaneous coronary intervention(PCI).Methods 80 patients with ACS and undergoing PCI were divided into the control group and the observation group by the random number table method,40 cases in each group.The control group was treated with routine antiplatelet therapy,oral administra-tion of aspirin and clopidogrel,while the observation group was treated with intensive antiplatelet therapy and tirofiban based on the treatment in the control group.The changes of platelet aggregation function and inflammation indices before and after treatment were compared between the two groups.The changes of QT dispersion in the two groups were monitored by electrocardiogram.Both two groups were followed up for 1 year,and the incidence rate of adverse events was analyzed statistically.Results Before treatment,there were no significant differences in platelet aggrega-tion indices (MPAR,PRU),levels of inflammatory factors (hs -CRP,sCD40L)and QT dispersion between the two groups (all P >0.05).After treatment,MPAR and PRU in the observation group were lower than those in the control group[(30.26 ±8.42)%,(114.36 ±10.26)U vs.(39.33 ±9.4)%,(143.86 ±12.65)U](t =4.542,11.454,all P <0.05),the levels of hs -CRP and sCD40L were lower than those in the control group[(2.12 ±0.62 )mg/L, (1.71 ±0.94)μg/L vs.(2.94 ±0.44)mg/L,(2.76 ±1.23)μg/L](t =6.748,4.289,all P <0.05),and QTd and QTcd were also lower than those in the control group [(25.41 ±3.32)ms,(26.12 ±4.26 )ms vs.(29.52 ± 2.98)ms,(30.51 ±3.97)ms](t =5.826,4.768,all P <0.05).During the follow -up,the incidence rate of rest-enosis or thrombosis in stent of the observation group was lower than that of the control group (2.50% vs.15.00%) (χ2 =3.913,P <0.05).Conclusion The application of tirofiban anti -platelet therapy in patients with ACS after PCI can reduce the inflammatory responses,reduce platelet aggregation rate,shorten QT dispersion and reduce the incidence of adverse events.

Value of QT Dispersion in Myocardial Remodeling and Prognosis in Heart Failure Patient with Preserved Ejection Fraction / 医学研究杂志

Objective To evaluate the value of QT dispersion in myocardial remodeling and prognosis in patients with chronic heart failure with preserved ejection fraction (HFpEF).Methods Totally 76 patients admitted to hospital due to HFpEF in the period between years 2013-2015 were recruited.A 12-lead ECG,chest radiograph,echocardiogram,and serum for biochemical analysis were obtained at baseline.Patients were followed for 10.3 ± 2.6 months,the basic information of patients,medication details,laboratory examination,echocardiography and other clinical data,and the mortality rate and the incidence of the disease were collected and analyzed.Results During the follow-up,11 patients died (14.5％) with QT dispersion for 81.6 ± 25.7ms.65 patients survived,including 27 cases of readmission for cardiovascular events (35.5％) with QT dispersion for 73.8 ± 24.7ms.The remaining 38 patients without cardiovascular events (50％) with QT dispersion 64.8 ± 28.7ms.Univariate analysis showed that QTcmax and QTcd were the risk factors for death and cardiovascular events in HFpEF patients (P ＜ 0.05).Cox's proportional hazards regression model analysis found that QTcd was the independent risk factors for death and cardiovascular events in HFpEF patients (P ＜ 0.05).Pearson's correlation analysis showed that QTcd was significantly related with left ventricular end systolic diameter (P ＜ 0.05),left ventricular end diastolic diameter (P ＜ 0.05).Conclusion QT dispersion has clinical value in the diagnosis of myocardial remodeling and prognosis in patients with HFpEF.

Influence of interventional treatment of ventricular septal defect on QT dispersion, corrected QT dispersion and the left ventricular voltage / 解放军医学杂志

Objective To investigate the influence of interventional treatment of ventricular septal defect (VSD) on QT dispersion (QTd), corrected QT dispersion (QTcd) and the left ventricular voltage. Methods Fifty patients with VSD, admitted from May 2010 to October 2011 for interventional occlusion therapy, were included in the present study. The electrocardiograms and echocardiography of the patients were analyzed before and 1 day and 6 months after interventional treatment, including QTd, QTcd, RV5, SV1, RaVL, SV3, left ventricular ejection fraction (EF) and fractional shortening (FS). The changes in QTd, QTcd and the left ventricular voltage (RV5+SV1, RaVL+SV3) were observed after interventional occlusion therapy. Results Compared with preoperative electrocardiogram, the QTd and QTcd were obviously shortened (P<0.05), and the left ventricular voltage (RV5+SV1, RaVL+SV3) declined significantly after interventional occlusion therapy (P<0.05). Conclusions The QTd and QTcd are shortened and left ventricular voltage lowered significantly after interventional occlusion treatment in VSD patients. Transcatheter interventional occlusion therapy can obviously improve electrical remodeling.

Alteraciones electrocardiográficas en anorexia nervosa: revisión crítica de la literatura / Electrocardiographic abnormalities in anorexia nervosa: a critical review of the literature

Introducción: La anorexia nervosa (AN) es un trastorno de la conducta alimentaria y, entre sus causas de mortalidad, las arritmias cardiacas y la muerte súbita son frecuentes, por lo que es indispensable la monitorización electrocardiográfica. Se han descrito muchos hallazgos con resultados contradictorios, por lo que es necesaria una revisión crítica de la literatura científica. Metodología: Revisión de los estudios relevantes sobre cambios electrocardiográficos en AN, consultados en PubMed desde 1974 hasta febrero de 2014, utilizando los términos MeSH: Eating disorders, nervosa anorexia, sinusal bradycardia, QT prolongation, QT dispersion, electrocardiography, EKG, electrocardiogram. Resultados y discusión: Las dos alteraciones más comunes reportadas incluyen la bradicardia sinusal y los cambios en la repolarización evidenciados en prolongación del QT e incremento de su dispersión. Los trastornos electrolíticos parecen ser la causa de estas alteraciones en algunos pacientes, pero otras razones se discuten en detalle, como la desviación del eje del QRS a la derecha, la alteración en variabilidad de la frecuencia cardiaca, R en derivación V6 de bajo voltaje, disminución de la amplitud del QRS y onda T y alargamiento del QRS. La mayoría de los autores hablan de reversibilidad de los cambios después del tratamiento. Conclusiones: Estos resultados siguen apoyando la necesidad de valorar a los pacientes con AN con electrocardiogramas inicial y de seguimiento, para el diagnóstico temprano y tratamiento de alteraciones cardiovasculares relacionadas con alta morbimortalidad. También apoyan la necesidad del uso racional de psicofármacos para no aumentar el riesgo de arritmias cardiacas y muerte súbita.

Background: Anorexia nervosa is an eating disorder in which cardiac arrhythmias and sudden death are frequent causes of mortality, which makes electrocardiographic monitoring indispensable in these patients. There are many suggestive findings but results are contradictory, making a critical review of the scientific literature is necessary. Methods: The most relevant studies on electrocardiographic (EKG) changes in patients with AN, found in PubMed from 1974 to February 2014, were reviewed using the MeSH terms: eating disorders, nervosa anorexia, sinus bradycardia, QT prolongation, QT dispersion, electrocardio graphy, EKG, and electrocardiogram. Findings and discussion: The two most common EKG findings reported in the literature are sinus bradycardia and changes in depolarization, as shown by prolongation and increased dispersion of the QT interval. Electrolyte disturbances seem to be the cause of these disturbances in some patients, but other reasons are also discussed in detail, such as QRS right axis deviation, disturbances of heart rate variability, low R wave voltage in V6, amplitude decrease of the QRS and T wave, and QRS prolongation. The majority of authors report that these changes are reversible after treatment of AN. Conclusions: These findings support the need for initial and follow-up EKGs in patients with AN and for early diagnosis and treatment of cardiovascular disturbances that are associated with morbidity and mortality. They also support the need for the rational use of psychop harmacology, and that does not increase the risk of arrhythmias and sudden death in these patients.

ECGEstudio: Herramienta para el diagnóstico de enfermedades cardiovasculares / ECGEstudio: Tool for the diagnosis of cardiovascular diseases

El objetivo del siguiente trabajo es exponer el diseño y las principales características de un sistema desarrollado para el análisis del ECG de reposo. Este está compuesto por: un módulo que adquiere el ECG y lo transmite vía USB, una computadora personal y una aplicación desarrollada sobre la tecnología .NET. Se realizan estudios de tendencia, no encontrados en los electrocardiógrafos tradicionales, para analizar la evolución de la Hipertrofia Ventricular, la tendencia a la Muerte Súbita y la recuperación posterior a un infarto cardiaco. Para el diseño del sistema, se siguió una estructura por capas con niveles de abstracción que faciliten su mantenimiento y actualización. Microsoft Visual Studio 2010 fue el entorno de desarrollo y SQL Server Compact el gestor de base de datos. El sistema fue evaluado con señales simuladas y provenientes de voluntarios con frecuencias cardíacas entre 30 y 240 latidos por minutos, obteniéndose una sensibilidad superior al 99 por ciento en la detección de complejos QRS(AU)

The aim of this paper is to discuss the main features of a system developed for the resting ECG analysis. The proposed system is composed of an electronic ECG module for signal acquisition and transmission via USB, a personal computer and a Windows application developed on .NET technology. Trend studies, based on several ECGs from a patient, are made to analyze the evolution of ventricular hypertrophy, the propensity to sudden death and the recovering degree after suffering a heart attack; this kind of study is not available in traditional electrocardiographs. The proposed was designed as a layered structure with levels of abstraction to facilitate their continued maintenance and updating. Microsoft Visual Studio 2010 was selected as the development environment and SQL Server Compact as the database manager. The system was tested with simulated ECGs and signals from volunteers with heart rates between 30 and 240 beats per minute, giving sensitivity in QRS complex detection over 99 percen(AU)

ECGEstudio: Herramienta para el diagnóstico de enfermedades cardiovasculares / ECGEstudio: Tool for the diagnosis of cardiovascular diseases

El objetivo del siguiente trabajo es exponer el diseño y las principales características de un sistema desarrollado para el análisis del ECG de reposo. Este está compuesto por: un módulo que adquiere el ECG y lo transmite vía USB, una computadora personal y una aplicación desarrollada sobre la tecnología .NET. Se realizan estudios de tendencia, no encontrados en los electrocardiógrafos tradicionales, para analizar la evolución de la Hipertrofia Ventricular, la tendencia a la Muerte Súbita y la recuperación posterior a un infarto cardiaco. Para el diseño del sistema, se siguió una estructura por capas con niveles de abstracción que faciliten su mantenimiento y actualización. Microsoft Visual Studio 2010 fue el entorno de desarrollo y SQL Server Compact el gestor de base de datos. El sistema fue evaluado con señales simuladas y provenientes de voluntarios con frecuencias cardíacas entre 30 y 240 latidos por minutos, obteniéndose una sensibilidad superior al 99 por ciento en la detección de complejos QRS(AU)

The aim of this paper is to discuss the main features of a system developed for the resting ECG analysis. The proposed system is composed of an electronic ECG module for signal acquisition and transmission via USB, a personal computer and a Windows application developed on .NET technology. Trend studies, based on several ECGs from a patient, are made to analyze the evolution of ventricular hypertrophy, the propensity to sudden death and the recovering degree after suffering a heart attack; this kind of study is not available in traditional electrocardiographs. The proposed was designed as a layered structure with levels of abstraction to facilitate their continued maintenance and updating. Microsoft Visual Studio 2010 was selected as the development environment and SQL Server Compact as the database manager. The system was tested with simulated ECGs and signals from volunteers with heart rates between 30 and 240 beats per minute, giving sensitivity in QRS complex detection over 99 percent(AU)

The effect of esmolol on corrected-QT interval, corrected-QT interval dispersion changes seen during anesthesia induction in hypertensive patients taking an angiotensin-converting enzyme inhibitor / Efeito de esmolol sobre o intervalo QT corrigido e alterações da dispersão do intervalo QT corrigido observadas durante a indução da anestesia em pacientes hipertensos que receberam um inibidor da enzima conversora de angiotensina / Efecto del esmolol sobre el intervalo QT corregido y alteraciones de la dispersión del intervalo QT corregido observadas durante la inducción de la anestesia en pacientes hipertensos que recibieron un inhibidor de la enzima convertidora de la angiotensina

BACKGROUND AND OBJECTIVES: The importance of minimizing the exaggerated sympatho-adrenergic responses and QT interval and QT interval dispersion changes that may develop due to laryngoscopy and tracheal intubation during anesthesia induction in the hypertensive patients is clear. Esmolol decreases the hemodynamic response to laryngoscopy and intubation. However, the effect of esmolol in decreasing the prolonged QT interval and QT interval dispersion as induced by laryngoscopy and intubation is controversial. We investigated the effect of esmolol on the hemodynamic, and corrected-QT interval and corrected-QT interval dispersion changes seen during anesthesia induction in hypertensive patients using angiotensin converting enzyme inhibitors. METHODS: 60 ASA I-II patients, with essential hypertension using angiotensin converting enzyme inhibitors were included in the study. The esmolol group received esmolol at a bolus dose of 500 mcg/kg followed by a 100 mcg/kg/min infusion which continued until the 4th min after intubation. The control group received 0.9% saline similar to the esmolol group. The mean blood pressure, heart rate values and the electrocardiogram records were obtained as baseline values before the anesthesia, 5 min after esmolol and saline administration, 3 min after the induction and 30 s, 2 min and 4 min after intubation. RESULTS: The corrected-QT interval was shorter in the esmolol group (p = 0.012), the corrected-QT interval dispersion interval was longer in the control group (p = 0.034) and the mean heart rate was higher in the control group (p = 0.022) 30 s after intubation. The risk of arrhythmia frequency was higher in the control group in the 4-min period following intubation (p = 0.038). CONCLUSION: Endotracheal intubation was found to prolong corrected-QT interval and corrected-QT interval dispersion, and increase the heart rate during anesthesia induction with propofol in hypertensive patients using angiotensin ...

JUSTIFICATIVA E OBJETIVO: É óbvia a importância de minimizar as respostas simpatoadrenérgicas exageradas e o intervalo QT e a dispersão do intervalo QT que podem ocorrer por causa de laringoscopia e intubação traqueal durante a indução da anestesia em pacientes hipertensos. Esmolol diminui a resposta hemodinâmica à laringoscopia e à intubação. Porém, o efeito de esmolol sobre a redução do intervalo QT prolongado e a dispersão do intervalo QT induzida pela laringoscopia e intubação é controverso. Pesquisamos o efeito de esmolol sobre a hemodinâmica e o intervalo QT corrigido e as alterações da dispersão do intervalo QT observadas durante a indução da anestesia em pacientes hipertensos que receberam inibidores da enzima conversora de angiotensina (IECA). MÉTODOS: Foram incluídos no estudo 60 pacientes, estado físico ASA I-II, com hipertensão arterial essencial e que receberam IECA. O grupo esmolol recebeu uma dose em bolus de 500 mcg kg-1, seguida por infusão contínua de 100 mcg kg-1 min-1 até o quarto minuto após a intubação. O grupo controle recebeu solução salina a 0,9%, semelhantemente ao grupo esmolol. Os valores da pressão arterial média e da frequência cardíaca e os registros do eletrocardiograma foram obtidos durante a fase inicial pré-anestesia, cinco minutos após a administração de esmolol e solução salina, três minutos após a indução e 30 segundos, dois minutos e quatro minutos após a intubação. RESULTADOS: O intervalo QT corrigido foi menor no grupo esmolol (p = 0,012), o intervalo de dispersão do intervalo QT corrigido foi maior no grupo controle (p = 0,034) e a frequência cardíaca média foi maior no grupo controle (p = 0,022) 30 segundos após a intubação. O risco da frequência de arritmia foi maior no grupo controle no quarto minuto após a intubação (p = 0,038). CONCLUSÃO: Descobrimos que a intubação traqueal prolonga o intervalo e a dispersão do intervalo QT corrigido e aumenta a frequência cardíaca durante a indução da ...

JUSTIFICACIÓN Y OBJETIVO: Es evidente la importancia que tiene minimizar las respuestas simpatoadrenérgicas exageradas y el intervalo QT y la dispersión del intervalo QT que pueden ocurrir a causa de la laringoscopia e intubación traqueal durante la inducción de la anestesia en pacientes hipertensos. El esmolol disminuye la respuesta hemodinámica a la laringoscopia y a la intubación. Sin embargo, su efecto sobre la reducción del intervalo QT prolongado y la dispersión del intervalo QT inducida por la laringoscopia e intubación es controvertido. Investigamos el efecto del esmolol sobre la hemodinámica y el intervalo QT corregido, y las alteraciones de la dispersión del intervalo QT observadas durante la inducción de la anestesia en pacientes hipertensos que recibieron inhibidores de la enzima convertidora de la angiotensina. MÉTODOS: Fueron incluidos en el estudio 60 pacientes, estado físico ASA I-II, con hipertensión arterial esencial y que recibieron inhibidores de la enzima convertidora de la angiotensina. El grupo esmolol recibió una dosis en bolos de 500 mcg/kg, seguida de infusión continua de 100 mcg/kg/min hasta el cuarto minuto después de la intubación. El grupo control recibió una solución salina al 0,9%, de forma similar al grupo esmolol. Los valores de la presión arterial media y de la frecuencia cardíaca y los registros del electrocardiograma fueron obtenidos durante la fase inicial preanestésica, 5 min después de la administración del esmolol y la solución salina, 3 min después de la inducción, y 30 s, 2 min y 4 min después de la intubación. RESULTADOS: El intervalo QT corregido fue menor en el grupo esmolol (p = 0,012), el intervalo de dispersión del intervalo QT corregido fue mayor en el grupo control (p = 0,034) y la frecuencia cardíaca media fue mayor en el grupo control (p = 0,022) 30 s después de la intubación. El riesgo de la frecuencia de arritmia fue mayor en el grupo control en el cuarto minuto después de la intubación ...

The study of the changes of QT dispersion and heart rate variability in children with ventricular contraction / 实用医学杂志

Objective To investigate the changes of QT dispersion and heart rate variability in children with ventricular contraction. Methods 50 healthy children who came for medical examinations at Chengdu Women′s and Children′s Central Hospital from January 2012 to January 2014 were selected as control group. 147 children with ventricular contraction admitted in Pediatric Intracardiac Department of Chengdu Women′s and Children′s Central Hospital from January 2012 to January 2014 were divided them into Benign Group (LownⅠ&LownⅡ) and Malignant Group(LownⅢ, LownⅣA, LownⅣB&LownⅤ) according to the results of Lown classification. Benign Group contained 90 cases while Malignant Group contained 57 cases. Difference in QT dispersion and indices of heart rate variability of the three groups were compared. Results There were no statistically differences between control group and benign group in QT dispersion (P > 0.05). QT dispersion of malignant group was much longer than that of control group and the differences had statistically meaning(P50 ms) of malignant group was much shorter than that of control group and benign group and the differences had statistically meaning (P< 0.01). SDNN, SDANN and SDNN index of benign group was shorter than that of control group and the differences had statistically meaning (P<0.05). Conclusions Heart rate variability of children with malignant ventricular contraction becomes significantly shorter and QT dispersion becomes significantly longer. Detection of QT dispersion and heart rate variability can effectively predict the risky degree of ventricular contraction in children.

QT Interval Abnormalities in Korean Women with Anorexia Nervosa / 대한정신약물학회지

OBJECTIVE: Anorexia nervosa carries the highest mortality of any psychiatric disorder with largely attributed to a cardiovascular etiology. The aim of this study was to evaluate QT alteration and the factors to influence the QT alteration. METHODS: We evaluated a hospital cohort of patients with anorexia nervosa (n=78) and age-matched healthy women (n=89). The QT, QT dispersion and U wave were measured from electrocardiograms in both patients and controls, and QT was corrected for heart rate using Bazett's formula. We also gathered the data for serum electrolytes, cholesterol, uric acid, creatinine, thyroid hormone, and bone mineral density. RESULTS: QT dispersion was significantly greater in patients with anorexia nervosa whereas corrected QT interval did not differ between groups. U wave tended to appear more frequently in patients with anorexia nervosa. QT dispersion was influenced by lowest ever body mass index and serum thyroid hormone. CONCLUSION: QT dispersion and U wave look to be more reliable index than heart rate-corrected QT, which may reflect arrhythmia potential in patients with anorexia nervosa. Lowest ever body mass index and current metabolic status could be predictive factors to cardiac arrhythmia in anorexia nervosa. Longitudinal follow-up study to evaluate risk as well as protective factors to cardiac mortality is warranted.