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Aim: The purpose of this research was to contrast (heart-rate corrected QT interval) QTc, and (QT dispersion) QTd intervals in individuals with (temporal lobe epilepsy) TLE and those without TLE using a standard 12-lead electrocardiogram. Patients & methods: This cross-sectional research was undertaken on 100 cases aged 10 to 20 diagnosed with epilepsy in accordance with 2017 ILAE criteria. The patients' informed written permission was acquired. In our study, we included 100 cases: 50 with TLE and 50 with non-TLE verified by seizure semiology. All patients were subjected to a comprehensive history, clinical examination (heart rate, pulse, and blood pressure), and clinical evaluation, which included a comprehensive epilepsy history. On the basis of neurology service documents or the initial publication of the international classification of diseases, 9th revision (ICD9) diagnostic or 10th revision (ICD10) codes for epilepsy, diagnostic age for epilepsy was calculated. Results: The mean QT interval in group I was 418.30±25.48 ms while that of group II was 406.20±27.63 ms, the mean QTc of group I was 513.60±61.94 ms and was 488.70±50.65 in group II. The calculated QTd was with a mean of 57.60±25.05 ms while that of group II was 43.60±31.89 ms. It means that the QT interval, QTc, and QTd values were considerably greater in the group I (temporal epilepsy) contrasted with group II (non-temporal epilepsy); (p=0.025, 0.030, and 0.016, respectively). The mean QT, QTc, and QTd values for FE were 409.20±20.80, 500.70±55.60, and 52.60±29.70 ms, respectively. QT, QTc, and QTd mean values for patients with widespread epilepsy were 412.00±25.60, 505.00±68.60, and 46.20±28.70 ms. QT, QTc, and QTd interval were insignificantly different between focal and generalized epilepsy. The longer an illness progresses, the longer the QT and QTc intervals, as there was a substantial positive correlation among illness's course and QT interval (r=0.391, p<0.001) and QTc interval (r=0.289, p=0.011), but there was no noticeable impact on QTd due to the illness's duration, as we found an insignificant correlation among duration of illness and QTC and QTd. Conclusions: Our findings indicate that; QTc interval and QTd are longer in epilepsy cases more among TLE cases contrasted with non-TLE. Since there was no distinction among different epilepsy types (focal and generalized). [ABSTRACT FROM AUTHOR]

ObjectiveMethodsResultsConclusionThe 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.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.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 (β = -0.299; p = 0.002) and QTcd (β = -0.300; p = 0.002) values independently.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. [ABSTRACT FROM AUTHOR]

Abstract 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

Background and Aim: Sodium-glucose co-transporter-2 (SGLT2) inhibitors added to optimal medical therapy have been shown to reduce the risk of cardiovascular death and recurrent heart failure (HF) hospitalization in HF patients. We aimed to evaluate the effect of SGLT2 inhibitors on the ventricular repolarization markers (VRM) in patients with HF with reduced ejection fraction (HFrEF). Methods: 51 patients with HFrEF who had symptoms New York Heart Association (NYHA) class II–IV despite optimal medical treatment and were added SGLT2 inhibitors to their treatment were included in the study. Electrocardiography (ECG) and laboratory results obtained before the treatment and at the first-month follow-up visit were compared. QT, QTc (corrected by Bazett formula), QT dispersion (QTd), QTc dispersion (QTc-d), Tpeak to Tend (Tp-e) interval, Tp-e/QT, and Tp-e/QTc ratios were measured and defined as VRM. Results: A significant decrease was observed in HR, QT, QTc intervals, and QTd compared to pre-treatment. While the mean Tp-e interval was 101.5 ± 11.7 ms before treatment, it decreased to 93.1 ± 12.7 ms after treatment (p < 0.001). There was a significant decrease in N-terminal pro-B-type natriuretic peptide (NT-proBNP) levels after treatment [2859 ± 681vs.1266 ± 763, respectively (p < 0.001)] and QTd, Tp-e interval, and Tp-e/QTc ratio was positively correlated with the change in NT-proBNP level. Conclusions: The addition of SGLT2 inhibitors to optimal medical therapy in HFrEF patients positively changes VRM (QT, QTc, QTd, Tp-e, and Tp-e/QTc). [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

The aim of this study was to examine the effect of exercise training on the double product (DP) and QT dispersion in patients after myocardial infarction and to determine whether the left ventricular ejection fraction (LVEF) had an effect on the benefit. A total of 375 patients with previous MI were included in the study. Patients were randomly divided into a group that was included in the exercise training program (TG: 329 patients) and a group that did not train (NTG: 46 patients). All patients underwent an echocardiographic examination, standard ECG, corrected QT dispersion (QTdc) and exercise test, after which the training group was included in the exercise training program lasting 21 days. Reduced left ventricular ejection fraction (RLVEF), less than 40%, was registered in 104 (31.6%) patients in TG, while in NTG it was registered in 16 (34.8%). At the beginning of the follow-up period, in TG, there was no significant difference in DP values, between patients with and without RLVEF (p-NS), while QTdc values were significantly higher in those with RLVEF (p < 0.001). After 21 days in TG, a significant decrease in DP (12.3 ± 1.8 vs. 11.7 ± 1.3 beat/min x mm Hg x103; p < 0.01) and QTdc (103.6 ± 28.3 vs. 96.1 ± 25.8 ms; p < 0.05) was registered in patients with RLVEF and a significant decrease in DP (11.9 ± 2.2 vs. 10.8 ± 1.6 beat/min x mmHg x103; p < 0.001) and QTdc (65.7 ± 25.4 vs. 58.6 ± 22.8 ms; p < 0.005) in those without RLVEF. In NTG patients, after a follow-up period of 21 days, no significant changes in DP and QTdc parameters were registered. The results show that exercise training has a beneficial effect on DP and QT dispersion in patients with previous MI. LVEF has a significant influence on the benefit of exercise training, patients without RLVEF have a better benefit. [ABSTRACT FROM AUTHOR]

Whether sodium–glucose cotransporter-2 inhibitors (SGLT2is) reduce ventricular arrhythmias and sudden cardiac death is controversial. Ventricular repolarization heterogeneity is associated with ventricular arrhythmias; however, the effect of SGLT2is on ventricular repolarization in patients with heart failure with reduced ejection fraction (HFrEF) has not been fully investigated. We prospectively evaluated 31 HFrEF patients in sinus rhythm who were newly started on dapagliflozin 10 mg/day. Changes in QT interval, corrected QT interval (QTc), QT dispersion (QTD), corrected QTD (QTcD), T peak to T end (TpTe), TpTe/QT ratio, and TpTe/QTc ratio were evaluated at 1-year follow-up. QT interval, QTc interval, QTD, QTcD, TpTe, and TpTe/QTc ratio decreased significantly at 1-year follow-up (427.6 ± 52.6 ms vs. 415.4 ± 35.1 ms; p = 0.047, 437.1 ± 37.3 ms vs. 425.6 ± 22.7 ms; p = 0.019, 54.1 ± 11.8 ms vs. 47.6 ± 14.7 ms; p = 0.003, 56.0 ± 11.2 ms vs. 49.4 ± 12.3 ms; p = 0.004, 98.0 ± 15.6 ms vs. 85.5 ± 20.9 ms; p = 0.018, and 0.225 ± 0.035 vs. 0.202 ± 0.051; p = 0.044, respectively). TpTe/QT ratio did not change significantly (0.231 ± 0.040 vs. 0.208 ± 0.054; p = 0.052). QT interval, QTD, and TpTe were significantly reduced 1 year after dapagliflozin treatment in patients with HFrEF. The beneficial effect of dapagliflozin on the heterogeneity of ventricular repolarization may contribute to the suppression of ventricular arrhythmias. Registry informationhttps://center6.umin.ac.jp/cgi-open-bin/ctr/ctr%5fview.cgi?recptno=R000049428. Registry number: UMIN000044902. [ABSTRACT FROM AUTHOR]

Aim:Gonadotropin-releasing hormone analogs (GnRHa) are standard medical treatments for precocious puberty. Studies on their side effects in adults have shown that these drugs can cause changes in electrocardiography (ECG), along with some cardiovascular effects; however, the number of studies on children is limited. This study investigated the effects of these drugs on ECG parameters in children diagnosed with central precocious puberty (CPP).Materials and Methods:This prospective study included 44 girls who were initiated GnRHa treatment and diagnosed with CPP. ECG was performed before treatment and repeated after 6 months of treatment.Results:The mean age of the children was 9.13±1.55 years. Leuprolide acetate (3.75 mg IM) was administered to all of the patients following the standard protocol. A comparison of the pre-treatment and 6-month ECG parameters revealed a prolonged QT interval after treatment, with a statistically significant difference (p0.05).Conclusion:Despite a significant increase in QT interval on ECG with GnRHa compared to pre-treatment ECGs, this increase was attributed to a variability in heart rate. Even if regular ECG monitoring is considered after initiation of GnRHa treatment, they are believed to be safe drugs in children.

Introduction: Coronavirus disease‐2019 (COVID‐19) has cardiac manifestations. Data about electrocardiogram (ECG) changes after COVID‐19 recovery is limited in hemodialysis patients. We aimed to investigate the changes in ventricular repolarization parameters after COVID‐19 recovery in hemodialysis patients. Methods: Fifty‐five hemodialysis patients who recovered from COVID‐19 infection were included. QT interval, Tp‐e interval, corrected QT (QTc), QTc dispersion, and Tp‐e dispersion values were determined on the patients' ECGs, taken before COVID‐19 and at least 1 month after recovery. The patients' data before COVID‐19 infection and after recovery were compared. Results: It was found that longest QTc (QTcmax) and QTc dispersion values after recovery were prolonged compared with pre‐infection period (427 ± 28 ms vs. 455 ± 26 ms, p = 0.000 and 39 ± 16 ms vs. 65 ± 20 ms, p = 0.000). Conclusion: In our hemodialysis patients, ventricular repolarization parameters increased after COVİD‐19 recovery. In hemodialysis patients, already predisposed to arrhythmic deaths, arrhythmia risk after COVİD‐19 recovery may become more pronounced. [ABSTRACT FROM AUTHOR]

Aim: Gonadotropin-releasing hormone analogs (GnRHa) are standard medical treatments for precocious puberty. Studies on their side effects in adults have shown that these drugs can cause changes in electrocardiography (ECG), along with some cardiovascular effects; however, the number of studies on children is limited. This study investigated the effects of these drugs on ECG parameters in children diagnosed with central precocious puberty (CPP). Materials and Methods: This prospective study included 44 girls who were initiated GnRHa treatment and diagnosed with CPP. ECG was performed before treatment and repeated after 6 months of treatment. Results: The mean age of the children was 9.13±1.55 years. Leuprolide acetate (3.75 mg IM) was administered to all of the patients following the standard protocol. A comparison of the pre-treatment and 6-month ECG parameters revealed a prolonged QT interval after treatment, with a statistically significant difference (p<0.001). There were no significant differences in the pre- and post-treatment values of PR, QRS, QT interval, QTc interval, QT dispersion, or QTc dispersion (p>0.05). Conclusion: Despite a significant increase in QT interval on ECG with GnRHa compared to pre-treatment ECGs, this increase was attributed to a variability in heart rate. Even if regular ECG monitoring is considered after initiation of GnRHa treatment, they are believed to be safe drugs in children. [ABSTRACT FROM AUTHOR]

Background: The purpose was to examine the electrocardiographic arrhythmia risk determinants of the QT and P-wave dispersions of the patients who have Antisocial Personality Disorder (ASPD) by comparing them with the healthy control group. Method: A total of 52 patients who were diagnosed with ASPD according to DSM-5 Criteria and a healthy control group that consisted of 54 people were included in the study. Twelve lead Electrocardiograms (ECGs) were obtained from all participants in the supine position and at rest, and P-wave dispersion and QT dispersion were also calculated. The participants were administered the Beck Anxiety Inventory (BAI), Beck Depression Inventory (BDI), Buss-Durke Aggression Scale (BDAS), Barratt Impulsivity Scale (BIS-11), and sociodemographic clinical data form. The SPSS version 22 package program was used for statistical analyses. Results: The mean age of the ASPD group and control group were no statistically significant differences between them (p=0.092). QT max (p=0.016), QTd (p

Aim:In this study, we evaluated changes in transmyocardial repolarization parameters in renal colic patients with severe pain. Our secondary aim was to evaluate the changes in these parameters after pain relief.Materials and Methods:The study was a prospective observational study. Patients with known urolithiasis and severe pain and without any cardiac disease were included. A control group was created from healthy volunteers of similar age and sex. Electrocardiography (ECG) were taken at the time of admittance and one hour after pain relief. The data were analyzed with the Statistical Package for the Social Sciences 16 program.Results:One hundred renal colic patients and 100 healthy volunteers were included in the study. Median age and sex of the patients in the patient group and the control group were similar. The heart rates and myocardial parameters of the patients were higher than those in the control group. In the patient group, heart rate, P wave duration, QTc, Tp-e interval and Tp-e/QTc rates were decreased in the ECGs that were taken after pain relief, and these differences were statistically significant (p

Introduction: This study aimed to evaluate the effects of dialysis on change of QT interval in pre-dialysis, 1 h after dialysis initiation, and post-dialysis period in patients on maintenance dialysis (MHD). Methods: An observational prospective study was conducted, including 61 patients, on thrice-weekly MHD ≥3 months, and without acute diseases, at the Nephrology-Dialysis Department of a tertiary hospital in Vietnam. The exclusive criteria were atrial fibrillation, atrial flutter, branch block, prolonged QT recorded in medical history, and taking antiarrhythmic drugs lengthening QT interval before entering the study. Twelve-lead electrocardiographs and blood chemistries were done simultaneously before, 1 h after initiation, and after the dialysis session. Results: The proportion of patients with prolonged QT interval increased significantly from 44.3% in pre-dialysis to 77% 1 h after dialysis initiation and 86.9% in post-dialysis session. Immediately after dialysis, the QT and QTc intervals on all 12 leads were significantly longer. Post-dialysis levels of potassium, chloride, magnesium, and urea decreased significantly from 3.97 (0.7), 98.6 (4.7), 1.04 (0.2), and 21.4 (6.1) to 2.78 (0.4), 96.6 (2.5), 0.87 (0.2), and 6.33 (2.8) mmol/L, respectively, whereas the calcium increased significantly from 2.19 (0.2) to 2.57 (0.2) mmol/L. There were significant differences in the potassium level at the dialysis initiation and its speed of reduction between the group without and with prolonged QT interval. Conclusions: There was an increased risk of prolonged QT interval in MHD patients regardless of the absence of the previous abnormal QT interval. Notably, this risk increased rapidly 1 h after the initiation of dialysis. [ABSTRACT FROM AUTHOR]

Background: The QT interval dispersion (QTd) was first developed as a measure of the variability in ventricular repolarization times over space. This study aimed for comparing Streptokinase vs primary PCI for ST-elevation myocardial infarction: a comparison of QTD before and after therapy. Methods: Two hundred patients who had a STEMI and were treated with streptokinase or primary PCI were included in this prospective observational trial. Two groups of identical size were created, one for patients who received fibrinolytic therapy and the other for those who underwent primary PCI. Reperfusion therapy was administered to all patients via primary PCI or fibrinolyt ics after a thorough history and physical examination, including a 12-lead electrocardiogram. Quantifying the QT interval and its variability. Results: The PCI group demonstrated significantly higher percent change of max QTD (P=0.001) and QTcD (P < 0.001). In patients with anterior or inferior infarctions, the median percent change of QTD was significantly higher in those who underwent PCI (-33%) than in those who underwent SK (-21.43%). Additionally, in patients with lateral or posterior infarctions, the median percent change of QTD was significantly higher in those who underwent PCI (-37.05%) than in those who underwent SK (-16.67%). Conclusion: QTD values were shown to decrease more in the primary PCI technique. This study demonstrated a greater reduction in the incidence of harmful arrhythmia after primary PCI was used to treat the arrhythmia, and an elevated QT interval is a risk factor for the development of such an arrhythmia. [ABSTRACT FROM AUTHOR]

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Data on how the heart is affected in Chronic Urticaria (CU), a common annoying chronic dermatological disease, is quite limited. The electrocardiographic parameters; P wave dispersion (PWD) and QT dispersion (QTD) have been consistently reported to be predictive for cardiac arrhythmias and morbidity. We aimed to detect asymptomatic cardiovascular involvement in terms of predisposition to arrhythmias in chronic urticaria. This cross-sectional study included 128 individuals: 64 with CU and 64 healthy controls. 12-lead surface electrocardiogram and Doppler echocardiography were performed on patients and controls. All of the cardiologic parameters such as P wave, PWD, QTD and corrected QTD (QTDc) parameters were obtained from ECG measurements. Maximum P wave duration and PWD were found to be higher in CU patients than controls (P= 0.035 and P [Med-Science 2022; 11(2.000): 574-80]

Abstract Background Carotid artery manipulation is not a special technique but reports of intraoperative ventricular fibrillation are rare. The risk of fatal arrhythmias may be hidden behind routine surgical techniques and anesthetic management. We focused on QT prolongation and QT dispersion. Case presentation A 77-year-old man underwent carotid endarterectomy and bailout stenting. Although there were no obvious preoperative risk factors for intraoperative ventricular tachyarrhythmia, ventricular fibrillation (VF) had occurred during a maneuver of the carotid artery under hypercapnia. QTc was prolonged from 317 ms before surgery to 458 ms before the onset of VF. QTc dispersion between leads II and III was also increased to 50 ms. Hypomagnesemia was noted after resuscitation by electrical defibrillation, adrenaline, and noradrenaline. Conclusions We considered that the combination of multiple risk factors led to the development of ventricular fibrillation. It should be noted that carotid artery manipulation has the potential to cause arrhythmias.

Objectives: The objective of this study investigated the relation between QT-dispersion (QTd) and both number of coronary artery disease and major adverse cardiovascular events (MACEs) among patients with type 2 diabetes after elective percutaneous coronary intervention (PCI). Methods: One hundred ischemic heart disease patients undergoing elective coronary angioplasty were included; 49 patients with diabetes (group I) and 51 patients without diabetes mellitus (group II). Based on the QTd parameter after PCI, both groups were subdivided into tertiles. Angiographic, electrocardiographic parameters, and MACE were compared. Results: Both QTd after PCI and delta QTd were correlated to the number of diseased coronary arteries and MACE in patients with diabetes compared to patients without diabetes. QTd was longer in patients with diabetes developing MACE than those without MACE (r = −0.31, P = 0.04). Conclusion: QTd after PCI and delta QTd are the independent predictors of MACE in patients with type 2 diabetes.

Background Prolonged myocardial contraction and QT interval duration may be found in ischemic viable myocardium, yet it is unclear if noninvasive examination of regional nonhomogeneous myocardial mechanics and QT duration may detect patients with significant coronary artery disease (CAD). Aim To assess the ability of cardiac mechanical and QTc dispersions to identify significant CAD in patients having chest pain with no prior myocardial infarction. Patients and methods We examined 125 patients who had chest pain and evaluated by coronary angiography. They are divided into two groups. CAD group included 75 patients with significant CAD, and control group included 50 patients without significant CAD. We used echocardiographic speckle tracking to calculate longitudinal strain. We measured cardiac contraction duration as the time between the ECG first deflection in QRS complex and longitudinal strain peak within every segment of the 17-segments left ventricular model. We measured mechanical dispersion by calculating the SD of 17-time intervals (dispersionSD17) or by subtracting the shortest contraction duration from the longest one (dispersion-delta). QTc dispersion was defined as the difference between the shortest and the longest QTc intervals as measured in the 12-lead ECG. We compared CAD group and control group regarding mechanical and QTc dispersions. Results The CAD group had longer average contraction duration than the control group (436.13 ± 51.97 vs. 417.79 ± 40.76 ms, P = 0.036), and the contraction duration was significantly associated with QTc interval (r = 0.501, P < 0.001). Mechanical dispersion had an independent correlation with CAD (P < 0.001), but QTc dispersion and duration did not exhibit a significant association with CAD. Mechanical dispersion exhibited an incremental value over global longitudinal strain, wall motion score index, and conventional risk factors in identifying significant CAD. Conclusions In individuals with no prior myocardial infarction, the myocardial mechanical and QTc dispersions can predict the existence of significant CAD. Cardiac mechanical dispersion has an incremental value on global longitudinal strain for identification of patients with significant CAD.

Background: Prolonged myocardial contraction and QT interval duration may be found in ischemic viable myocardium, yet it is unclear if noninvasive examination of regional nonhomogeneous myocardial mechanics and QT duration may detect patients with significant coronary artery disease (CAD). Aim: To assess the ability of cardiac mechanical and QTc dispersions to identify significant CAD in patients having chest pain with no prior myocardial infarction. Patients and methods: We examined 125 patients who had chest pain and evaluated by coronary angiography. They are divided into two groups. CAD group included 75 patients with significant CAD, and control group included 50 patients without significant CAD. We used echocardiographic speckle tracking to calculate longitudinal strain. We measured cardiac contraction duration as the time between the ECG first deflection in QRS complex and longitudinal strain peak within every segment of the 17-segments left ventricular model. We measured mechanical dispersion by calculating the SD of 17-time intervals (dispersionSD17) or by subtracting the shortest contraction duration from the longest one (dispersion-delta). QTc dispersion was defined as the difference between the shortest and the longest QTc intervals as measured in the 12-lead ECG. We compared CAD group and control group regarding mechanical and QTc dispersions. Results: The CAD group had longer average contraction duration than the control group (436.13 ± 51.97 vs. 417.79 ± 40.76 ms, P = 0.036), and the contraction duration was significantly associated with QTc interval (r = 0.501, P < 0.001). Mechanical dispersion had an independent correlation with CAD (P < 0.001), but QTc dispersion and duration did not exhibit a significant association with CAD. Mechanical dispersion exhibited an incremental value over global longitudinal strain, wall motion score index, and conventional risk factors in identifying significant CAD. Conclusions: In individuals with no prior myocardial infarction, the myocardial mechanical and QTc dispersions can predict the existence of significant CAD. Cardiac mechanical dispersion has an incremental value on global longitudinal strain for identification of patients with significant CAD. [ABSTRACT FROM AUTHOR]

Background: The QT dispersion (QTd) can be used as effective reperfusion marker among cases who undergo primary Percutaneous Coronary Intervention (PCI) after having acute myocardial infarction. Objective: Study of the correlation between myocardial perfusion and QT dispersion on 12 lead surface ECG among patients who had acute ST-elevation myocardial infarction (STEMI) managed by primary PCI. Patients and methods: In a prospective cohort study, 100 cases admitted to the Cardiology Departments of Zagazig University Hospital and El-Zaitoun Specialized Hospital within 12 hours of symptom onset were recruited. This study included all patients who fulfilled the criteria for acute STEMI and were candidates for primary PCI. All cases underwent electrocardiogram (ECG), echocardiogram (ECHO), and coronary angiogram. Results: Myocardial electrical heterogeneity was rapidly restored to normal after effective reperfusion, whereas insufficient tissue reperfusion (Myocardial blush grade (MBG) lower or equal to 2) even with Thrombolysis in Myocardial Infarction (TIMI) III flow, was not related to the resolution of the increased QTd. QTd and corrected QTD (QTcd) were significantly shortened following recanalization of the infarct-related artery among cases with successful tissue-level myocardial reperfusion (MBG3). The pre-procedural QTd is a significant predictor of the patients' MBG (i.e., The MBG improves with lower pre-procedural QTd values and worsens with higher QTd values.) Conclusion: Effective revascularization of myocardial tissue was determined by MBG related to normal electrical heterogeneity restoration with reduction of QTd in the jeopardized myocardium. The pre-procedural QTd is a significant predictor of the patients' MBG. [ABSTRACT FROM AUTHOR]

Introduction: Familial hypercholesterolemia (FH) is an autosomal dominant inherited disease associated with high lowdensity lipoprotein cholesterol (LDL-C) levels that can lead to early cardiovascular disease. Apart from its atherosclerotic effect, it can cause cardiac dysfunction by various mechanisms. QT dispersion is a measure reflecting the heterogeneity of ventricular repolarization that has been investigated as an early or important marker in various pathologies. The aim of this study is to investigate QT dispersion and its possible clinical effects in patients with familial hypercholesterolemia. Method: Our study was conducted in patients who applied to the cardiology and endocrinology outpatient clinics of Mersin City Training and Research Hospital between 30.10.2018 and 01.11.2019. Over the age of 18 who were diagnosed with familial hypercholesterolemia included to the study. Patients with an atherosclerotic risk factor and established disease were excluded from the study. The ECGs of the patients were transferred to digital media and evaluated by two different cardiologists and their averages were recorded. These values were compared with the control group. The results were recorded in the SPSS 20.0 package program and statistical analysis was performed. Results: A total of 200 patients were included in the study. 120 (60%) of them are women, the mean age is 32.28±7.90 years. LDL, total cholesterol and triglyceride values of the group with hypercholesterolemia were significantly higher than the other group (p<0.001, p<0.001, p=0.003). When the ECG parameters of the patients were compared, QT dispersion and QTc dispersion values were found to be significantly higher in the familial hypercholesterolemia group (p=0.001, p<0.001, p<0.001). In the logistic regression analysis, it was observed that QT dispersion (OR:0.100, 95%Cl:0.018-0.556, p=0.009) and QTc dispersion (OR:102.746, 95%Cl:4.441-2377.259, p=0.004) were statistically significant independent variables. Conclusion: QTd and QTcd measurements increased statistically significantly in familial hypercholesterolemia patients compared to the control group. It was detected in the patient group without atherosclerotic risk factors or established disease which reinforces its clinical significance. [ABSTRACT FROM AUTHOR]

BackgroundThe heart is commonly involved in COVID-19, and rhythm disorders have been largely reported.ObjectiveTo evaluate the association of some non-cardiac and cardiac comorbidities and QT dispersion with arrhythmias and their impact on outcomes in hospitalized patients with COVID-19.MethodsEach patient underwent cardiac telemetry monitoring through the entire hospitalization period, laboratory analyses, 12-lead ECG, and lung imaging examination. Patients with arrhythmia were divided into three groups (bradyarrhythmias, tachyarrhythmias, and tachy- and bradyarrhythmias).ResultsTwo-hundred patients completed the study (males, 123; mean age, 70.1 years); of these, 80 patients (40%) exhibited rhythm disorders on telemetry. Patients with arrhythmia were older (p < 0.0001), had a greater number of comorbidities (p < 0.0001), higher values of creatinine (p = 0.007), B-type natriuretic peptide (p < 0.0001), troponin (p < 0.0001), C-reactive protein (p = 0.01), ferritin (p = 0.001), D-dimer (p < 0.0001), procalcitonin (p = 0.0008), QT interval (p = 0.002), QTc interval (p = 0.04), and QTc dispersion (p = 0.01), and lower values of sodium (p = 0.03), magnesium (p = 0.04), glomerular filtration rate (p < 0.0001), and hemoglobin (p = 0.008) as compared to patients without arrhythmia. By comparing the three subgroups of patients, no significant differences were found. At multivariate analysis, age [odds ratio (OR) = 1.14 (95% CI: 1.07–1.22); p = 0.0004], coronary artery disease [OR = 12.7 (95% CI: 2.38–68.01); p = 0.005], and circulating troponin [OR = 1.05 (95% CI: 1.003–1.10); p = 0.04] represented risk factors independently associated with arrhythmia. All-cause in-hospital mortality was ∼40-fold higher among patients with arrhythmia [OR = 39.66 (95% CI: 5.20–302.51); p = 0.0004].ConclusionArrhythmias are associated with aging, coronary artery disease, subtle myocardial injury, hyperinflammatory status, coagulative unbalance, and prolonged QTc dispersion in patients with COVID-19, and confer a worse in-hospital prognosis. Given its usefulness, routinary use of cardiac telemetry should be encouraged in COVID wards.

Introduction: Diabetes Mellitus imbricates inflammatory processes on their pathophysiology, it could affect cardiac electrophysiology. Cardiac inflammatory process leads electrocardiogram changes. Nevertheless, there are discrepancies about whether it prolongs or decreases waves and intervals such as QRS and QT. Furthermore, QRS dispersion has not been studied. Objective: To identify QRS complex and QT interval modifications in type 2 diabetic patients. Methods: A descriptive cross-sectional study was carried out in 59 type 2 diabetic patients selected by non-probabilistic sampling. Electrocardiogram was performed, QRS and QT interval were measured manually by two observers. Dispersion of both variables was calculated to compare with normal values. Results: Two variables showed differences for sex, QRS dispersion was higher in females (45.84), p=0.0001 vs. reference value; QT dispersion (63.12) showed significance difference (p=0.0246) vs. reference value for males. Greater than five years of illness was related to higher QRS values (124.11 vs. 137.28), p=0.005 and corrected QT dispersion (61.81 vs. 78.79), p=0.022. Conclusions: The electrocardiographic differences between sexes may suggest a gender influence. The longer duration of diabetes diseases could increase cardiovascular risk of arrhythmias due to greater QRS duration and corrected QT interval prolongation. [ABSTRACT FROM AUTHOR]

Background: Ventricular repolarization measurement by QTc interval and QT dispersion can recognize high-risk patients. Previous research tended to evaluate the act of repolarization indicators alone but this study aimed to elucidate their prognostic utility before and after modifying confounding parameters in risk stratification of different aspects of prognosis in decompensated heart failure patients with systolic dysfunction. Methods: Data of 98 variables were evaluated to determine their predictive value concerning arrhythmic events, in-hospital, and long-term mortality. Results: From 858 cases that presented with acute heart failure, 19.2% (n=165) were enrolled in the study. During hospitalization, arrhythmic events and cardiac-related mortality occurred in 56(33.9%) and 11(7%) patients, respectively. QTc and QT dispersion were independent predictors of arrhythmia and in-hospital mortality after adjustment of the variables (arrhythmic events: QTc interval OR 1.085, P=0.007, QT dispersion OR 1.077, P=0.007, in-hospital mortality: QTc interval OR 1.116, P=0.009, QT dispersion OR 1.067, P=0.011). After being discharged, they were tracked for 181±56 days. Within the 16 deaths in follow-up time, 6 sudden cardiac deaths were documented. Cox regression, defined QTc as the predictor of all-cause and sudden death mortality (all-cause: HR 1.041, 95% CI 1.015-1.067, P=0.002; sudden death: HR 1.063, 95% CI 1.023-1.105, P=0.002); nevertheless, efforts to demonstrate QT dispersion as the predictor failed. Conclusion: The predictive nature of QT parameters was significant after modification of the variables; therefore, they should be measured for risk stratification of ventricular repolarization arrhythmia and death in decompensated heart failure patients. [ABSTRACT FROM AUTHOR]

Background: Fibromyalgia (FM) and chronic fatigue syndrome (CFS) frequently overlap clinically and have been considered variants of one common disorder. It is characterized by diffuse musculoskeletal pain and discomfort. Many studies confirmed the increased risk of heart rate abnormalities in FM patients. So, the aim of this study was to assess p wave dispersion and QT interval changes in female Egyptians with fibromyalgia. Results: The mean QT and QTc dispersions were significantly lower in FM group compared with the HC group (p<0.001 for both). The minimum QT interval was significantly higher in the FM group (p<0.001). Regarding mean P wave dispersion, it was lower in FM group compared with the HC group but the result was not statistically significant (p=0.088). Relation between patient’s results and types of graft used showed no statistically significant differences between them. Conclusion: FM patients had abnormal repolarization manifested as prolonged QTcd which makes them at higher risk for developing ventricular arrhythmias and sudden cardiac death. [ABSTRACT FROM AUTHOR]

Data on how the heart is affected in Chronic Urticaria (CU), a common annoying chronic dermatological disease, is quite limited. The electrocardiographic parameters; P wave dispersion (PWD) and QT dispersion (QTD) have been consistently reported to be predictive for cardiac arrhythmias and morbidity. We aimed to detect asymptomatic cardiovascular involvement in terms of predisposition to arrhythmias in chronic urticaria. This cross-sectional study included 128 individuals: 64 with CU and 64 healthy controls. 12-lead surface electrocardiogram and Doppler echocardiography were performed on patients and controls. All of the cardiologic parameters such as P wave, PWD, QTD and corrected QTD (QTDc) parameters were obtained from ECG measurements. Maximum P wave duration and PWD were found to be higher in CU patients than controls (P= 0.035 and P<0.001, resp). There were significant correlations between CU duration and PWD (r = 0.348, P = 0.005) and between Urticaria Activity Score and QTD and QTDc (r = 0.351, P = 0.004 and r = 0.361, P = 0.003 resp). Multiple linear regression analysis showed that; systolic blood pressure and CU duration are independently associated with PWD (β =0.344, p=0.003 and β=0.375, p=0.001 resp) and also that; diastolic blood pressure and disease activity (UAS7) are independently associated with both QTD (β=0.320, p=0.006 and β=0.377, p=0.001 resp) and QTDc (β=0.344, p=0.003 and β=0.389, p=0.001 resp). In patients suffering from Chronic Urticaria, PWD and QTD were significantly increased as compared to control group of healthy individuals. PWD was associated with disease duration while QTD and QTDc was associated with the disease activity. [ABSTRACT FROM AUTHOR]

Aim:B12 vitamin deficiency may cause cardiac autonomic dysfunction, heart rate variability, endothelial dysfunction and subclinical atherosclerosis, a significant degree of reduction in heart ejection fraction and deformation of the left ventricular myocardium. We aimed to investigate the effect of B12 deficiency in children on cardiac electrical activity by comparing the Tp-e and QT dispersion values between healthy children and children with B12 deficiency.Methods:The demographic data, laboratory results electrocardiography and echocardiography results of isolated B12 patients (n=64) with vitamin B12 deficiency and control group (n=64) included in the study between 15.3.2020 and 15.06.2020 were prospectively recorded and comparatively analyzed.Results:A total of 128 patients included in the study. Corrected QT (QTc) value and Tp-e interval, were statistically significantly higher in the patient group (p

Introduction. Cardiovascular disease (CVD) is the common cause of mortality in end-stage renal disease (ESRD) patients undergoing hemodialysis (HD). Causes of CVD in ESRD patients are multifactorial. Ventricular arrhythmia is known as the leading cause of sudden death in dialysis patients. QT dispersion, which is measured from electrocardiography (ECG), is known as one of the parameters to assess the risk of arrhythmia in HD patients. This study aimed to determine the proportion of pre-dialysis prolonged QT dispersion in chronic twice-weekly HD patients and the associated factors. Methods. A cross-sectional study was conducted among HD patients age ≥18 years with dialysis duration of at least three months in Cipto Mangunkusumo Hospital during May–June 2019. Electrocardiography, echocardiography, and blood samples were taken before the dialysis session. Bivariate analysis using Chi-square and Fisher’s exact test was performed on each variable. Significant results were further analysed using logistic regression. Results. A total of 142 subjects were included in this study. The mean age of subjects was 49 (standard deviation (SD) 15) years. Prolonged QT dispersion was found in 51 subjects (35.9%). Multivariate analysis showed prolonged QT dispersion was significantly correlated with systolic dysfunction (PR=1.875 (CI 95% 1.234-2.848); p=0.006) and left ventricle hypertrophy (PR=2.361 (CI 95% 1.032-5.403); p=0.019). Age, diabetes mellitus, hypokalemia, hypomagnesemia, and diastolic dysfunction were not significantly correlated with QT dispersion (p>0.05). Conclusion. The proportion of pre-dialysis prolonged QT dispersion in twice-weekly chronic hemodialysis patients in RSCM is 35.9% and associated with systolic dysfunction and left ventricle hypertrophy.

Clinical and experimental electrophysiological studies have shown the importance of inhomogeneous myocardial repolarization in ventricular arrhythmias' genesis. Increased dispersion of repolarisation provides a substrate for ventricular arrhythmias by generating functional unidirectional block areas, thereby predisposing to reentry. QT dispersion, defined as the difference between the longest and the shortest QT interval on the surface ECG, is a validated measure of repolarisation dispersion. QT dispersion predicts sudden death and ventricular arrhythmias in patients with chronic heart failure from coronary heart disease and various cardiac diseases

Background. Coronary atherosclerosis is an ongoing pathological process, varying from asymptomatic forms to angina pectoris, myocardial infarction and even sudden cardiac death. Early identification of persons with an increased risk of the severe atherosclerosis will promote adequate diagnostic and therapeutic measures to prevent cardiovascular complications. Aim. To make a prognostic model determining the probability of a severe coronary atherosclerosis in cardiac patients. Material and methods. The actual study included 116 patients of cardiology departments with various degree of coronary atherosclerosis measured by coronary angiography: group I 70% coronary stenosis (50% in case of left main coronary artery), group II those with less severe atherosclerotic process. All patients underwent electrocardiography (ECG) at rest and Holter monitoring. Pathological Q-waves, qualitative and quantitative characteristics of ventricular extrasystoles as well as QRS-fragmentation were assessed in all cases. In individuals having sinus rhythm, heart rate turbulence (HRT), T-wave alternans and QT, QTc dispersion on maximum and minimum heart rate were additionally calculated. Results. The prognostic model included the following ECG-markers: HRT, pathological Q-waves, QTc dispersion on maximum heart rate and QRS-fragmentation in lateral leads (I, AVL, V6). All parameters have demonstrated a direct relationship with the likelihood of severe coronary atherosclerosis. The current model took into account 71% of the factors influencing significant atherosclerosis, AUC=0.940.04, the sensitivity and the specificity were 90.0 and 94.4% respectively. Conclusion. A comprehensive assessment of the ECG data helps to identify the group with an increased risk of severe coronary atherosclerosis among cardiac patients.

Introduction Smoking increases the risk of arrhythmia. QT dispersion (QTd) is an important indicator for the determination of ventricular arrhythmia. In this study, we aimed to determine the arrhythmia risk by evaluating QTd in smokers and to assess the relationship between the level of nicotine addiction and carbon monoxide (CO) level in the expiratory air. Methods This study was designed as a single-center, cross-sectional study. Among the chronic smokers referred to the Smoking Cessation Clinic of a tertiary hospital between October 2019 and January 2020, all those who had no risk factors for cardiac arrhythmias, except smoking, were included in the study. Sociodemographic data and smoking characteristics of the participants were collected and exhaled CO levels were measured. QT intervals were measured in all leads by using a 12-lead standard electrocardiogram (ECG), and heart rate corrected QT (QTc) intervals, QT dispersion (QTd), and corrected QT dispersion (QTcd) were calculated. Results The mean age of the 250 patients was 37.2±9.3 years and the majority of patients (65%) were male. The mean amount of smoking was 25.74±16.03 packs/year and the mean value of CO was 12.36±7.06 ppm. The mean QTd was 23.83±13.12 ms, and the mean QTcd was 26.63±15.02 ms. A statistically significant relationship was found between QTd and QTcd and level of addiction, consumption of sticks/day and packs/year, and exhaled CO values (all p

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. [ABSTRACT FROM AUTHOR]

Background: Numerous studies have shown that QT dispersion (QTd) can be a suitable criterion for risk assessment of arrhythmia in patients with congenital heart disease. Pulmonary arterial hypertension (PAH) increases the risk of cardiac arrhythmia by changing ventricular repolarization homogeneity. In this study, we assessed QTd changes after PDA device closure and the effect of PAH on these changes. Methods: Between October 2018 and March 2021, 97 patients (48 males; 49 females; mean age 31.36 ± 4.26 months; range 3 months to 14 years) who satisfied the primary inclusion criteria and did not meet the exclusion criteria and underwent PDA device closure intervention were included in the study. Echocardiography was performed before the procedure. QT corrected (QTc), and QTd and PR intervals were measured according to the patients' standard 12‐lead ECGs in two periods, preoperative (1 day) and after (3 months). Results: In the general group, QTc and QTd decreased significantly after PDA closure. Based on our classification of the patients in two groups of high PAP and normal PAP, the three parameters QTc, QTd, and PR interval were assessed separately in the two groups. All three parameters decreased significantly in the normal PAP and high PAP groups. Conclusions: However, a left‐to‐right shunt through the patent ductus arteriosus can affect ventricular repolarization; this effect seems to be particularly more significant when there is pulmonary hypertension. [ABSTRACT FROM AUTHOR]

Objectives: The objective of this study investigated the relation between QT-dispersion (QTd) and both number of coronary artery disease and major adverse cardiovascular events (MACEs) among patients with type 2 diabetes after elective percutaneous coronary intervention (PCI). Methods: One hundred ischemic heart disease patients undergoing elective coronary angioplasty were included; 49 patients with diabetes (group I) and 51 patients without diabetes mellitus (group II). Based on the QTd parameter after PCI, both groups were subdivided into tertiles. Angiographic, electrocardiographic parameters, and MACE were compared. Results: Both QTd after PCI and delta QTd were correlated to the number of diseased coronary arteries and MACE in patients with diabetes compared to patients without diabetes. QTd was longer in patients with diabetes developing MACE than those without MACE (r = -0.31, P = 0.04). Conclusion: QTd after PCI and delta QTd are the independent predictors of MACE in patients with type 2 diabetes. [ABSTRACT FROM AUTHOR]

Background: Carotid artery manipulation is not a special technique but reports of intraoperative ventricular fibrillation are rare. The risk of fatal arrhythmias may be hidden behind routine surgical techniques and anesthetic management. We focused on QT prolongation and QT dispersion. Case presentation: A 77-year-old man underwent carotid endarterectomy and bailout stenting. Although there were no obvious preoperative risk factors for intraoperative ventricular tachyarrhythmia, ventricular fibrillation (VF) had occurred during a maneuver of the carotid artery under hypercapnia. QTc was prolonged from 317 ms before surgery to 458 ms before the onset of VF. QTc dispersion between leads II and III was also increased to 50 ms. Hypomagnesemia was noted after resuscitation by electrical defibrillation, adrenaline, and noradrenaline. Conclusions: We considered that the combination of multiple risk factors led to the development of ventricular fibrillation. It should be noted that carotid artery manipulation has the potential to cause arrhythmias. [ABSTRACT FROM AUTHOR]

Abstract Background Cardiac arrhythmias are expected among patients with epilepsy due to the effect of anti-epileptic drugs. Temporal lobe epilepsy also causes autonomic seizures that may affect heart rhythm. Prolongation of the corrected QT interval and QT dispersion is a risk factor for cardiac arrhythmia. Objectives We aimed to assess corrected QT interval and QT dispersion in patients with epilepsy and if there is a difference between patients with temporal epilepsy versus non-temporal epilepsy. Methods This study was conducted on 100 patients (50 patients with temporal epilepsy and 50 patients with non-temporal epilepsy) and 50 age- and sex-matched healthy controls. They underwent a prolonged (6 to 24 h) 22 channel computerized electroencephalogram monitor with a 10–20 system. QT dispersion, QT interval, and corrected QT interval (using Bazett’s formula) were calculated. Results This study showed significantly higher QT dispersion and corrected QT interval in patients with epilepsy when compared to the age- and sex-matched control group (P < 0.001, P < 0.001). Also, the corrected QT interval and QT dispersion were significantly higher in temporal epilepsy patients when compared to the non-temporal group (P < 0.001, P < 0.001). Conclusion Corrected QT interval and QT dispersion are higher in epileptic patients and more among temporal epilepsy patients in comparison to non-temporal epilepsy patients.

Abstract Background QT dispersion (QTd) is related to regional variations in myocardial repolarization. Our study aims to assess the value of QTd in prediction of myocardial ischemia and its severity during stress imaging. We enrolled one hundred patients having stable coronary artery disease (CAD) and fulfilling the “Appropriateness criteria for cardiac radionuclide imaging” (MPI). They were divided into group I including patients with MPI-detected ischemia (50 patients) and group II including patients with normal perfusion scan (50 patients). We excluded unstable CAD and all other causes affecting QTd. During isotope scan, ECGs were taken and QTd was calculated at rest and at maximum heart rate. Results QTd was significantly higher in the ischemic group both at rest and exercise (P = 0.000). QTd difference, the difference between QTd at rest and stress, was calculated. QTd difference was significantly lower in normal than in ischemic group (P = 0.003). There was a significant positive correlation between QTd difference and defect size (P = 0.04). Conclusion QTd increases in ischemia and the QTd difference (between rest and stress) correlates positively with severity of ischemia. QTd and QTd difference could be used to improve the accuracy of stress imaging test.

Abstract Background Carbon monoxide causes electrical, functional, and morphological changes in the heart. It is unclear, however, whether the indicators of myocardial damage can predict the patient’s prognosis after carbon monoxide poisoning. This retrospective study aimed to investigate the relationship between the carboxyhemoglobin level and electrocardiographic (ECG) changes and whether the ECG changes and troponin I levels are related to the patient’s prognosis after carbon monoxide poisoning. Methods Carboxyhemoglobin, troponin I, and ECG parameters were measured in 70 patients with carbon monoxide poisoning. The QT and RR intervals were measured for each ECG lead in all patients, and the corrected QT interval and corrected QT dispersion were calculated. Results The correlation between the maximum corrected QT interval and the carboxyhemoglobin level was significant (P = 0.0072, R 2 = 0.1017), as were the relationships between QT dispersion and carboxyhemoglobin (P

Background: Metabolic syndrome is a constellation of cardiovascular risk factors characterized by insulin resistance, prothrombotic and pro-inflammatory state. This study was an attempt to evaluate ECG changes as markers for metabolic syndrome before development of overt cardiovascular disease. Aims: We evaluated association between metabolic syndrome and ECG indices: QT dispersion, QTc dispersion, TpTe interval and TpTe/QT ratio. Settings and Design: Cross-sectional study Methods and Material: The study was conducted on 108 patients with metabolic syndrome and compared with age and sex matched 50 controls. Indices were measured from 12 lead ECG and data was compared. Statistical analysis used: SPSS Results: Metabolic syndrome was more common in females with most common criteria present being waist circumference followed by hypertriglyceridemia Metabolic syndrome group had higher levels of BMI, waist circumference, fat percentage, serum triglycerides and fasting glucose, systolic and diastolic pressure as well as lower HDL levels than control subjects. The QTc dispersion, QT dispersion, TpTe intervals and TpTe/QT ratio were significantly increased in Metabolic syndrome group compared to the control group. Increased Odd's ratio of the ECG parameters in comparison with the control group was also calculated. ROC curve revealed that QTc dispersion and TpTe/ QT ratio were better predictors for future metabolic syndrome. Conclusions: Hence ECG indices (QT dispersion, QTc dispersion, TpTe interval and TpTe/ QT ratio) can be used to predict cardiovascular risk in such patients.

Hiroaki Okayasu,1 Takahiro Shinozaki,1 Yumiko Takano,1 Norio Sugawara,1 Kumiko Fujii,2 Norio Yasui-Furukori,1 Yuji Ozeki,2 Kazutaka Shimoda1 1Department of Psychiatry, Dokkyo Medical University, Tochigi, Japan; 2Department of Psychiatry, Shiga University of Medical Science, Shiga, JapanCorrespondence: Hiroaki Okayasu Tel +81 282-86-1111Email hokayasu@dokkyomed.ac.jpPurpose: Antipsychotic drugs have been implicated as risk factors for QT prolongation, which is a predictor of sudden cardiac death. However, the QT interval is considered an imperfect marker for proarrhythmic risk. Recently, improved methods, namely, QT dispersion (QTD), QTD ratio (QTDR), T wave peak-to-end interval (Tp-e), Tp-e/QT ratio and Tp-e/QTc ratio, have been regarded as proarrhythmic risk markers. We attempted to reevaluate the risk of sudden cardiac death due to antipsychotics use by measuring these improved evaluation methods.Patients and Methods: We retrospectively evaluated QTc, QTD, QTDR, Tp-e, Tp-e/QT ratio and Tp-e/QTc ratio from the medical records of 410 patients with schizophrenia diagnosed by the Diagnostic and Statistical Manual of Mental Disorders, 4th Edition, Text Revision, or 5th Edition. Information on drugs administered was obtained from medical records. We investigated the correlation between each index on ECG and medication, such as antipsychotics, prescribed to participants with linear regression analysis. We also compared each index between 235 healthy controls and 235 patients matched for age and sex.Results: Positive correlations between QTc and levomepromazine and brexpiprazole were identified. Levomepromazine and lithium were positively correlated with QTD. Levomepromazine, quetiapine, asenapine, clozapine and carbamazepine were positively correlated with QTDR. Levomepromazine, olanzapine, brexpiprazole and lithium were positively correlated with Tp-e. Olanzapine, brexpiprazole and lithium were positively correlated with the Tp-e/QT ratio. Olanzapine, brexpiprazole and lithium were positively correlated with Tp-e/QTc ratio. Significant differences in all indexes were noted between the patients and healthy controls.Conclusion: According to our results, the prediction of the risk of sudden cardiac death by each index was inconsistent. We should evaluate the predictive factor of ventricular arrhythmia according to various electrocardiogram indexes because QTc alone could not identify the risk of sudden cardiac death.Keywords: antipsychotic drugs, sudden cardiac death, electrocardiogram, QT prolongation, QT dispersion, T peak-to-end interval

Abstract Background Numerous studies have shown that QT dispersion (QTd) can be a suitable criterion for risk assessment of arrhythmia in patients with congenital heart disease. Pulmonary arterial hypertension (PAH) increases the risk of cardiac arrhythmia by changing ventricular repolarization homogeneity. In this study, we assessed QTd changes after PDA device closure and the effect of PAH on these changes. Methods Between October 2018 and March 2021, 97 patients (48 males; 49 females; mean age 31.36 ± 4.26 months; range 3 months to 14 years) who satisfied the primary inclusion criteria and did not meet the exclusion criteria and underwent PDA device closure intervention were included in the study. Echocardiography was performed before the procedure. QT corrected (QTc), and QTd and PR intervals were measured according to the patients’ standard 12‐lead ECGs in two periods, preoperative (1 day) and after (3 months). Results In the general group, QTc and QTd decreased significantly after PDA closure. Based on our classification of the patients in two groups of high PAP and normal PAP, the three parameters QTc, QTd, and PR interval were assessed separately in the two groups. All three parameters decreased significantly in the normal PAP and high PAP groups. Conclusions However, a left‐to‐right shunt through the patent ductus arteriosus can affect ventricular repolarization; this effect seems to be particularly more significant when there is pulmonary hypertension.

Introduction: QT interval represents the ventricular depolarization and repolarization. Its accurate measurement is critical since prolonged QT can lead to sudden cardiac death. QT is affected by heart rate and is corrected to QTc via several formulae. QTc is commonly calculated on the ECG and not the 24‐h Holter. Methods: 100 patients presenting to our institution were evaluated by an ECG followed by a 24‐h Holter. QTc measurement on both platforms using Bazett and Fridericia formulae was recorded and compared. Results: Mean age was 14.09 years, with the majority being males. Mean heart rate was 125.87. In the ECG, the mean QTc interval via the Bazett formula was 0.40 s compared with 0.38 s using the Fridericia formula. The mean corrected QT via the Bazett formula was 0.45, 0.39, and 0.42 s for the shortest RR, the longest RR, and the average RR, respectively. In contrast to the Fridericia formula, the corrected QT interval was 0.40, 0.39, and 0.40 s for the shortest RR, the longest RR, and the average RR, respectively. Using the Bazett formula, the highest specificity was reached during the longest RR interval (92.2%), while the highest sensitivity was recorded during the shortest RR interval (40%). As for the Fridericiaformula, sensitivity always reached 0%, while the highest specificity was reached during the average RR interval. Conclusion: QTc measured during Holter ECG reached a high specificity regardless of RR interval using the Fridericia and during the longest and the average RR interval for the Bazett formula. The consistently low sensitivity reveals that Holter ECG should not be used to rule out prolonged QT. [ABSTRACT FROM AUTHOR]

Background: Coronavirus disease‐2019 (COVID‐19) has been associated with an increased risk of acute cardiac events. However, the effect of COVID‐19 on repolarization heterogeneity is not yet established. In this study, we evaluated electrocardiogram (ECG) markers of repolarization heterogeneity in patients hospitalized with COVID‐19. In addition, we performed a systematic review and meta‐analysis of the published studies. Methods: QT dispersion (QTd), the interval between T wave peak to T wave end (TpTe), TpTe/QT (with and without correction), QRS width, and the index of cardio‐electrophysiological balance (iCEB) were calculated in 101 hospitalized COVID‐19 patients and it was compared with 101 non‐COVID‐19 matched controls. A systematic review was performed in four databases and meta‐analysis was conducted using Stata software. Results: Tp‐Te, TpTe/QT, QRS width, and iCEB were significantly increased in COVID‐19 patients compared with controls (TpTe = 82.89 vs. 75.33 ms (ms), p‐value =.005; TpTe/QT = 0.217 vs. 0.203 ms, p‐value =.026). After a meta‐analysis of 679 COVID‐19 cases and 526 controls from 9 studies, TpTe interval, TpTe/QT, and TpTe/QTc ratios were significantly increased in COVID‐19 patients. Meta‐regression analysis moderated by age, gender, diabetes mellitus, hypertension, and smoking reduced the heterogeneity. QTd showed no significant correlation with COVID‐19. Conclusion: COVID‐19 adversely influences the ECG markers of transmural heterogeneity of repolarization. Studies evaluating the predictive value of these ECG markers are warranted to determine their clinical utility. [ABSTRACT FROM AUTHOR]

Background: Although COVID-19 primarily presents with respiratory-related symptoms, there is interplay between COVID-19 and the cardiovascular system. The aim of the present study was to detect QT/QT dispersion in COVID-19 non-cardiac patients. Methods: These prospective cohort studyincluded patients admitted to isolation department at Zagazig University Hospitals. The data was collected from the pre-treated COVID-19 patientswho diagnosed according to the World Health Organization. Electrocardiogram (ECG), echocardiography forLVEF, presence of wall motion abnormality, E, E/A, ē -TD, E/ē, LA Volume and LAVI were performed. Results: COVID-19 patients who had DM showed higher incidence of MACE 10.0%(p=0.012), and 18.9% of diabetic patients suffered from MACEs. There was a statistically significant higher value of D dimer, FBS, WBC and neutrophil among COVID19 patients who developed MACEs compared to other COVID19 patients (p<0.05 The best cut-off value of QTc in the prediction of MACEs was =443.5 msec Logistic regression analysis identified that independent predictors of MACEs occurrence among COVID-19 patients were increase: temperature, FBS, WBCs, neutrophil, D-dimer, Qtc; odds of having MACEs is 11.2 times greater in presence of diastolic dysfunction, 8 times greater in presence of ECG abnormality as opposed to normal. Conclusion: We confirmed that there is an increase of QT dispersion (as an ECG predictors) in COVID-19 patients before treatment compared to recovery. There is a good relation between occurrence of MACEs in COVID-19 patients and QTc. [ABSTRACT FROM AUTHOR]

Leukocyte apheresis is necessary in various cellular therapies. However, maintenance of a stable flow rate during leukocyte apheresis is often difficult, even in patients or donors without major problems. Despite this, predictive methods and evidence regarding the reality of the situation are limited. We conducted a retrospective analysis involving adult patients who required leukocyte apheresis for the treatment of neoplasms using WT1-pulsed dendritic cell vaccine. Monocytes were separated from apheresis products to obtain dendritic cells. All the patients were pre-evaluated based on laboratory and chest X-ray findings and subjected to an identical apheresis procedure. The occurrence of poor blood collecting flow during leukocyte apheresis was monitored, and the frequency, clinical information, and associated risk factors were analyzed. Among 160 cases, poor blood collecting flow was observed in 53 cases (33.1%) in a median time of 54 min (range, 2-127 min) post-initiation of leukocyte apheresis. Owing to difficulty in obtaining higher collecting flow, a longer procedure time was required, and in some cases, the scheduled apheresis cycles could not be completed. Consequently, the number of harvested monocytes was low. Multivariable analysis indicated that female patients have an increased risk of poor inlet flow rate. Furthermore, prolonged QT dispersion (QTD) calculated using Bazett's formula was found to be a risk factor. Although the patients did not present any major problems during leukocyte apheresis, poor blood collecting flow was observed in some cases. Sex and pre-evaluated QTD might be useful predictors for these cases; however, further prospective evaluation is necessary. [ABSTRACT FROM AUTHOR]

Abstract Background The risk stratification of coronary heart disease (CHD) and/or heart failure (HF) patients with easily measured electrocardiographic markers is of clinical importance. The aim of this meta‐analysis is to indicate whether increased QT dispersion (QTd) is associated with fatal and nonfatal outcomes in patients with CHD and/or HF. Methods We systematically searched MEDLINE and Cochrane databases without restrictions until August 15, 2018 using the keyword “QT dispersion”. Studies including data on the association between QTd and all‐cause mortality, sudden cardiac death (SCD) or arrhythmic events in patients with HF and/or CHD were classified as eligible. Results In the analysis including patients with CHD and/or HF, we found that QTd did not differ significantly in patients with SCD compared to no SCD patients while QTd was significantly greater in the group of all‐cause mortality patients and in patients who experienced a sustained ventricular arrhythmia. Subgroup analysis showed that in myocardial infarction studies, QTd was significantly higher in patients with an arrhythmic event compared to arrhythmic event‐free patients while a nonsignificant difference was found in QTd in patients who died from any cause compared to survivors. Similarly, in HF patients, the QTd was significantly greater in patients with an arrhythmic event while a nonsignificant difference was found regarding all‐cause mortality and SCD outcomes. Conclusions QTd has a prognostic role for stratifying myocardial infarction or HF patients who are at higher risk of arrhythmic events. However, no prognostic role was found regarding all‐cause mortality or SCD in this patient population.