Evaluation of ventricular repolarization in dermatomyositis and relationship with inflammation and autoimmunity.

Dermatomyositis (DM) is a chronic multi-systemic inflammatory disorder of autoimmune origin, which has been associated with cardiovascular complications, including ventricular arrhythmias and sudden cardiac death. The Tp-e interval and Tp-e/QT ratio have been accepted as new markers for the assessment of myocardial repolarization and ventricular arrhythmogenesis. The aim of this study was to evaluate ventricular repolarization by using Tp-e interval and Tp-e/QT ratio in patients with DM, and to assess the relation with inflammation and autoimmunity. This study included 281 DM patients (180 females, 101 males; mean age 52.73 ± 15.80 years) and 281 control subjects (180 females, 101 males; mean age 53.38 ± 15.72 years). QTc, Tp-e interval and Tp-e/QT ratio were measured from the 12-lead ECG. The plasma level of blood routine test, C-reactive protein (CRP), erythrocyte sedimentation rate (ESR) was measured. These parameters were compared between groups. No statistically significant difference was found between two groups in terms of basic characteristics. In electrocardiographic parameters analysis, QTc, Tp-e interval and Tp-e/QT ratio were significantly increased in DM patients compared to the control group (441.44 ± 26.62 ms vs 422.72 ± 11.7 ms, 104.16 ± 24.34 ms vs 77.23 ± 16.25 ms and 0.27 ± 0.06 ms vs 0.20 ± 0.04 ms, all P value < 0.01). QTc, Tp-e interval and Tp-e/QT were positively correlated with NLR, CRP, and ESR (all P values < 0.01), and were increased in anti-Ro/SSA-52kD positive patients compared to those negative (452.33 ± 24.89 ms vs 438.55 ± 26.37 ms, 114.05 ± 22.68 ms vs 101.53 ± 24.13 ms, and 0.29 ± 0.06 ms vs 0.27 ± 0.05 ms, all P value < 0.01). Our study demonstrated that QTc, Tp-e interval, and Tp-e/QT ratio were increased in DM patients and were associated with inflammatory markers and anti-Ro/SSA-52kD positivity.

The assessment of adolescent obesity's effects on ventricular repolarization.

BACKGROUND: Currently, there is a lack of research on the Tp-Te interval and Tp-e/QT ratio in obese adolescents who have metabolic syndrome. AIM: Our study aims to compare established ventricular repolarization parameters with these intervals and ratios in obese adolescents with or without metabolic syndrome, alongside a healthy control group, while exploring the association of these repolarization parameters with cardiovascular risk factors and echocardiographic variables. METHODS: The study included 100 obese adolescents and 50 lean subjects, with the obese participants categorized into two subgroups. The Tp-Te interval was identified as the duration from the peak to the end of the T wave. RESULTS: The metabolic and non-metabolic syndrome obese groups exhibited significantly elevated QTc and TpTe values compared to the control group, with no statistically significant differences observed in minimum QT, maximum QT, QT dispersion, QTc dispersion, TpTe dispersion, and TpTe/QT ratio values among obese subjects with metabolic or non-metabolic syndrome and controls. Specifically, TpTe values were significantly elevated in the non-metabolic syndrome obese groups compared to controls, while minimum TpTe values were significantly elevated in the metabolic syndrome obese groups compared to controls, and the prolongation of the QTc interval was notably elevated in the obese groups than in controls. CONCLUSIONS: Obese adolescents demonstrated an elevated TpTe interval compared to healthy controls, without any significant differences observed in TpTe dispersion, and TpTe/QT ratio values between the two groups. Results of our study showed that a negative correlation between TpTe and HDL-cholesterol and a positive correlation between the TpTe/QT ratio and insulin sensitivity indices in adolescents with metabolic syndrome.

The Tp-e/QT ratio as a predictor of nocturnal premature ventricular contraction events in patients with obstructive sleep apnea.

BACKGROUND: Obstructive sleep apnea (OSA) is significantly associated with a higher risk of ventricular arrhythmia (VA). QT, the Tp-e/QT ratio, and QT dispersion (QTd) are used to evaluate myocardial repolarization and are highly correlated with VA. The aim was to evaluate the predictive value of the Tp-e/QT ratio and other electrocardiogram (ECG) parameters for nocturnal premature ventricular contractions (PVCs) in patients with OSA. METHODS: We retrospectively analyzed data from patients with OSA and conducted a 1:1 matched cohort study. Patients diagnosed with OSA who met our criteria for the PVC group, and sex- and age-matched patients with OSA who met our criteria for the control group were enrolled in the study. The Tp-e, Tp-e/QT ratio, corrected QT interval (QTc), corrected Tp-e interval (Tp-ec), and QTd were measured, calculated and analyzed. RESULTS: Patients in the PVC group (n = 31) showed a greater Tp-e, Tp-ec, QTc, Tp-e/QT ratio, and QTd than patients in the control group (n = 31). In the univariate binary logistic regression analysis, higher Tp-ec (OR: 1.025; P = 0.042), QTc (OR: 1.014; P = 0.036), Tp-e/QT ratio (OR: 1.675; P < 0.001), and QTd (OR: 1.052; P = 0.012) values were all significantly associated with nocturnal PVCs. In multivariate analysis and receiver operating characteristic analysis, a higher Tp-e/QT ratio (OR: 2.168; 95% CI: 0.762-0.952; P < 0.001) was an independent predictor of nocturnal PVCs. CONCLUSIONS: The QTc, Tp-e/QT ratio, and QTd in patients with OSA with nocturnal PVCs were significantly increased compared with those in patients without nocturnal PVCs. A prolonged Tp-e/QT ratio was an independent predictor of nocturnal PVCs in patients with OSA.

Cardio-ankle brachial index is associated with prolonged Tp-e interval in patients with arterial hypertension.

AIM: The cardio-ankle vascular index (CAVI) is a marker of arterial stiffness, and elevated CAVI values have been reported to be associated with an increased risk of cardiovascular mortality and cardiac arrhythmia. This study aimed to evaluate the relationship between Tp-e interval and CAVI, which is associated with cardiac arrhythmia on electrocardiography (ECG). METHOD: The study included patients with hypertension whose blood pressure values were taken under control with optimal medical treatment. Arterial stiffness and CAVI were measured using the vascular scanning system VaSera VS-1000. The patients were divided into two groups as CAVI<9 and CAVI≥9. Ventricular repolarization markers QT and QTc intervals, Tp-e interval, and Tp-e/QT and Tp-e/QTc ratios were measured using 12­lead ECG. RESULTS: Tp-e interval (78.7 ± 10.3 vs. 63.6 ± 9.1, p < 0.001), Tp-e/QT ratio (0.018 ± 0.02 vs. 0.015 ± 0.02, p < 0.001), and Tp-e/QTc ratio (0.17 ± 0.02 vs. 0.14 ± 0.04, p = 0.025) were statistically significantly higher in the CAVI≥9 group compared to the CAVI<9 group. In the prediction of patients in the CAVI≥9 group, Tp-e interval had an area under the curve value of 0.862 (0.784-0.940, p < 0.001) at the cut-off point of >72.5 msec, indicating a statistically significant result. Left CAVI and right CAVI were found to be significantly correlated with Tp-e interval (r = -0.650, p < 0.001 and r = -0.663, p < 0.001, respectively). CONCLUSION: We found that elevated CAVI values were associated and positively correlated with prolonged Tp-e interval values in patients with hypertension. Patients with elevated CAVI values should be followed up closely to prevent cardiac arrhythmic events.

Effect of Smokeless Tobacco (Maras Powder) on the Epicardial Fat Thickness and Ventricular Repolarization Parameters.

Background and Objectives: Smokeless tobacco (ST) use has recently become an alternative to cigarettes, and it has been concluded that ST is at least as harmful as cigarettes. ST use is thought to play a role in the pathogenesis of arrhythmia by affecting ventricular repolarization. In this study, we aimed to examine the relationships of Maras powder (MP), one of the ST varieties, with epicardial fat thickness and new ventricular repolarization parameters, which have not previously been described. Materials and Methods: A total of 289 male individuals were included in this study between April 2022 and December 2022. Three groups, 97 MP users, 97 smokers, and 95 healthy (non-tobacco), were compared according to electrocardiographic and echocardiographic data. Electrocardiograms (ECG) were evaluated with a magnifying glass by two expert cardiologists at a speed of 50 m/s. Epicardial fat thickness (EFT) was measured by echocardiography in the parasternal short- and long-axis images. A model was created with variables that could affect epicardial fat thickness. Results: There were no differences between the groups regarding body mass index (p = 0.672) and age (p = 0.306). The low-density lipoprotein value was higher in the MP user group (p = 0.003). The QT interval was similar between groups. Tp-e (p = 0.022), cTp-e (p = 0.013), Tp-e/QT (p =0.005), and Tp-e/cQT (p = 0.012) were higher in the MP user group. While the Tp-e/QT ratio did not affect EFT, MP predicted the epicardial fat thickness (p < 0.001, B = 0.522, 95%CI 0.272-0.773). Conclusions: Maras powder may play a role in ventricular arrhythmia by affecting EFT and causing an increase in the Tp-e interval.

Assessment of Tp-e interval, Tp-e/QT, and Tp-e/QTc ratios in patients with acromegaly.

BACKGROUND: Cardiovascular complications, including ventricular arrhythmias associated with abnormalities of ventricular repolarization, are the leading cause of morbidity and mortality in patients with acromegaly. Herein, we aimed to investigate ventricular repolarization using Tp-e interval, Tp-e interval/QT, and Tp-e interval/QTc ratios in acromegalic patients compared to healthy subjects. METHODS: A total of 29 patients (aged 51.9 ± 11.2, 65.5% women) with acromegaly and 30 control subjects (aged 47.3 ± 14.4, 63.3% women) were enrolled in the study. Tp-e and QT interval, corrected QT (QTc), Tp-e/QT, and Tp-e/QTc ratios were calculated from the 12-lead electrocardiogram. RESULTS: Tp-e interval (89.28 ± 12.16 vs. 75.97 ± 9.92 ms; p < 0.001), Tp-e/QT ratio (0.237 ± 0.045 vs. 0.212 ± 0.029; p = 0.019), and Tp-e/ QTc ratio (0.218 ± 0.031 vs. 0.195 ± 0.026; p = 0.003) were significantly higher in patients with acromegaly compared to control group. A positive correlation was determined between left atrial volume index (LAVI) and Tp-e interval (r = 0.272, p = 0.039). DISCUSSION: The current study is the first to have shown significantly increased Tp-e interval, Tp-e/QT ratio, and Tp-e/QTc ratio were increased in acromegalic patients. These results may be important for screening malignant arrhythmic events in acromegaly.

Tp-e interval, Tp-e/QT, and Tp-e/QTc ratios in patients with primary hyperparathyroidism and their relationship with cardiac arrhythmic events.

BACKGROUND: Primary hyperparathyroidism (PHPT) is an endocrine disorder characterized by hypercalcemia caused by excessive parathyroid hormone (PTH) secretion from the parathyroid gland. PHPT was previously shown to increase cardiac arrhythmias. Besides, new indices, such as the Tpeak-Tend (Tp-e) interval, Tp-e interval/QT interval (Tp-e/QT) ratio, and Tp-e interval/corrected QT interval (Tp-e/QTc) ratio may be associated with ventricular arrhythmias and sudden cardiac death. Therefore, we aimed to investigate the relationship between PHPT and the changes to Tp-e interval, Tp-e/QT ratio, and Tp-e/QTc ratio. METHODS: We carried out the study with 41 patients with PHPT and 40 control subjects. We calculated the Tp-e interval, Tp-e/QT ratio, and Tp-e/QTc ratio of the participants from the V5 derivations on their ECG papers. While we defined Tp-e interval as the distance between the peak and the end of the T wave, Tp-e/QT and Tp-e/QTc ratios were calculated by dividing Tp-e by QT and Tp-e by QTc, respectively. RESULTS: Total calcium, albumin-corrected calcium, phosphorus, and PTH levels were significantly higher in patients with PHPT. We also found positive correlations between albumin-corrected calcium and PTH levels and Tp-e interval, Tp-e/QT ratio, and Tp-e/QTc ratio (p < 0.001). DISCUSSION: : Our results suggest that Tp-e may enhance the current knowledge on arrhythmic risk in PHPT patients better than basal ECG. In addition, both high PTH and high calcium levels appear to have the potential to cause arrhythmogenic effects.

Effect of noise on the electrocardiographic parameters.

PURPOSE: Noise, defined as any sound that is unpleasant, is one of the most important environmental problems. Prolonged exposure to noise has been shown to be associated with the development of cardiovascular diseases. No study investigated the effect of noise on surface electrocardiography (ECG). AIMS: The aim of our study is to investigate the effect of noise on surface ECG parameters including P-wave dispersion (PWD), QT intervals, corrected QT interval (QTc), T-wave peak to end (Tp-e) interval, and Tp-e/QT and Tp-e/QTc ratios. METHODS: A total of 51 people working in the textile factory affected by the noise and 43 volunteers without any disease and who were not exposed to noise were included in this study. The average noise level in the textile factory was 112 dB. A 12-lead ECG was obtained from all individuals. PR interval, PWD, QRS duration, QT interval, QTc interval, Tp-e interval, and Tp-e/QT and Tp-e/QTc ratios were calculated for all individuals. RESULTS: The noise group had significantly increased PWD [35 (28-40) vs. 28 (22-36) p = 0.029], QT interval ( 373.5 ± 27.3 vs. 359.3 ± 2.74, p = 0.001), QTc interval [(409 ± 21 vs. 403 ± 13 p = 0.045)], Tp-e interval [(90.6 ± 6.0 vs. 83.5 ± 7.3 p < 0.001)], Tp-e/QT [(0.24 ± 0.03 vs. 0.23 ± 0.02, p = 0.015)] and Tp-e/QTc [(0.22 ± 0.02 vs. 0.21 ± 0.02 p < 0.001)] compared to control group. Also, duration of working was positively correlated with PWD (r = 0.468, p = 0.001) and Tp-e/QTc ratio (r = 0.328, p = 0.019). In multiple linear regression linear regression analysis, noise was the independent predictor of both PWD (ß = 0.244, p = 0.032) and Tp-e/QTc (ß = 0.319, p = 0.003) CONCLUSION: We showed that noise significantly increased PWD, QT and Tp-e interval measurements. Also, noise was the independent predictor for both PWD and Tp-e/QTc.

The effect of Systolic and diastolic blood pressure on Tp-e interval in patients divided according to World Health Organization classification for body mass index.

Background: Tp-e interval, Tp-e/QT ratio and Tp-e/QTc ratio are electrocardiographic markers and indices of ventricular arrhythmogenic events. We aimed to investigate ventricular repolarization in normal weight, overweight, obese and morbidly obese individuals by using ECG parameters including the above markers.Methods: A total of 310 obese patients with various cardiac complaints, who were admitted to our outpatient clinic between May 2020 and January 2021, were prospectively included in the study. Using the World Health Organization (WHO) body mass index (BMI) classification, patients were divided into four groups: normal weight (18.5-24.9 kg/m2, n = 48), overweight (25-29.9 kg/m2, n = 98), obese (30-39.9 kg/m2, n = 119), and morbidly obese (>40 kg/m2, n = 45).Results: The morbidly obese and normal groups were younger in age than the other two groups. The Tp-e interval values for Groups I-IV were 72.1 ± 6.9, 73.1 ± 6.2, 75.7 ± 7.3 and 81.1 ± 6.9, respectively, and significantly different (P < .001). We found that age, BMI, systolic blood pressure (BP) and diastolic BP were independent predictors of a prolonged Tp-e interval.Conclusions: The principal finding of our study was the gradual increase in Tp-e interval, Tp-e/QT ratio and Tp-e/QTc ratio starting from the overweight stage and these parameters gradually increase in obese and morbidly obese patients. Additionally, systolic and diastolic blood pressure predicted Tp-e interval, Tp-e/QT ratio and Tp-e/QTc ratio.

The effect of low iron storage without Anaemia on electrocardiography.

BACKGROUND: Low iron storage is a common health problem around the world. Although the association of low iron storage with cardiovascular events and various electrocardiographic parameters has been investigated, its association with fragmented QRS (fQRS), Tpeak-Tend (Tp-e) interval, Tp-e/QT and Tp-e/QTc ratios, which are important criteria for repolarization, has not been studied in adults. METHODS: A total of 201 female patients in the 18-50 age group with no history of chronic and cardiac disease or anaemia were included in the study. Patients were divided into 3 groups based on their ferritin levels. Twelve lead EKGs were obtained from each patient, and fQRS, Tp-e interval, Tp-e/QT and Tp-e/QTc ratios were calculated manually. RESULTS: A total of 201 female patients with an average age of 37 ± 9 were included in the study. Group 1 (ferritin<15 ng/mL) consisted of 79 (39.3%) patients, Group 2 (ferritin 15-30 ng/mL) consisted of 64 patients (31.8%) and Group 3 (ferritin≥30 ng/mL) consisted of 58 (28.9%) patients. Tp-e interval was significantly higher in Group 1 compared to Group 2 and 3 (p < 0.001). A similar relationship was also observed between Tp-e/QT, Tp-e/QTc and fQRS (p < 0.001). A moderate, negative relationship was found in the correlation analysis of Tp-e, Tp-e/QT, Tp-e/QTc and fQRS with ferritin value [r = -0.519 (p = 0.001), r = -0.485 (p = 0.001), r = -0.540 (p = 0.001) and r = -0.345 (p = 0.001), respectively]. CONCLUSION: As a result of the study, it was found that low iron storage may increase arrhythmogenic susceptibility through increased fragmented QRS presence, increased Tp-e interval, Tp-e/QT and Tp-e/QTc ratios in healthy women of childbearing age.

The impact of fever on myocardial repolarization parameters.

BACKGROUND: It has been reported in the literature that the increase in body temperature shortens QT interval on electrocardiogram through heart rate modulation. However, the effects of fever on ventricular repolarization are not clearly known. This study elaborates on QT interval of isolated fever, corrected QT (cQT), Tp-e interval, the ratio of corrected Tp-e (cTp-e) and Tp-e/QT, and their impacts on arrhythmia potential. METHODS: This prospective study was performed on 74 patients without any active and chronic diseases other than fever and upper respiratory tract infection. The study included patients at the age of 18-50 years suffering from fever above 38.2 °C. QT and Tp-e intervals of the patients were measured from their ECGs taken in febrile and afebrile periods. cQT and cTp-e values were calculated according to Bazett, Fridericia, and Framingham formulations. RESULTS: QT and Tp-e intervals were observed to be shorter in the febrile period (p < 0.001 and p = 0.006 respectively). cTp-e was found to be longer in the febrile period according to Bazett, Fridericia, and Framingham formulations (p < 0.001, p = 0.002, p < 0.001, respectively). Tp-e/QT ratio was found to be higher in the febrile period than in the afebrile period (p < 0.001). CONCLUSION: Although QT, cQT, and Tpe intervals were shorter, cTpe interval and Tpe/QT ratio were longer and higher in the febrile period, respectively. These findings may indicate that fever may create a proarrhythmic effect by causing variability in the transmural distribution of myocardial repolarization.

Comprehensive non-invasive assessment of electrocardiographic abnormalities and cardiac arrhythmias in patients with genetically confirmed mitochondrial diseases.

BACKGROUND: There is limited data on cardiac arrhythmias and ventricular repolarization and dispersion abnormalities in patients with mitochondrial diseases (MitD). METHODS: Consecutive 40 patients with genetically proven MitD and 35 healthy controls were studied. Among other examinations all subjects underwent 24-h Holter recording and 12­lead electrocardiography (ECG) with corrected QT (QTc), QT dispersion (QTd), Tp-e and Tp-e/QT ratio assessment. RESULTS: Patients with MitD were 55.4 ± 15.7 years old, the disease duration was 18.5 ± 10.3 years, presented 6 clinical syndromes while mitochondrial and nuclear DNA type of mutation was present in 40 and 60% of cases, respectively. In MitD more frequently 1st degree atrioventricular block and intraventricular conduction defects were observed and also QRS complex duration was increased. Mean values of QTc (p = 0.001), QTd (p = 0.02), Tp-e (p < 0.00001) and Tp-e/QT (p < 0.00001) were significantly higher in MitD than in controls. Correlations between disease duration and PR interval duration (p = 0.003) and Creatine Kinase MB isoenzyme activity (p = 0.02) were found. No differences in depolarization and dispersion parameters were observed according to type of mutation or dominant clinical syndromes. In addition to supraventricular extrasystoles, nonsustained supraventricular tachycardias occurred more frequently in MitD (in 45.0 vs 14.3%, p = 0.0004). Ventricular arrhythmias were rare and observed almost exclusively in subjects with mitochondrial DNA mutation. CONCLUSIONS: In contrast to healthy controls, in MitD patients intraventricular, repolarization and dispersion disturbances were more frequently observed. In addition to bradyarrhythmias observed in some defined MitD syndromes, supraventricular rather than ventricular arrhythmias are more common.

Novel markers of ventricular repolarization are associated with mortality in patients undergoing surgical aortic valve replacement for severe aortic stenosis.

INTRODUCTION: Aortic stenosis (AS) is the most common degenerative valvular heart disease that can affect left ventricular functions. Tp-e interval and Tp-e/QT ratio is a novel repolarization marker which is associated with adverse cardiovascular events in several cardiovascular diseases. In our study, our aim is to investigate the prognostic effect of Tp-e interval, Tp-e/QT and Tp-e/QTc ratios on mortality in patients who underwent successful surgical aortic valve replacement (AVR). METHODS: A total of three hundred seventy-five patients undergoing successful surgical AVR were included in this study. Then, patients were divided into two groups according to mortality as group 1 without mortality (342 patients) and group 2 with mortality (33 patients). Tp-e interval, Tp-e/QT, and Tp-e/QTc ratios were calculated for both groups. RESULTS: Tp-e interval (71 (63.7-77); 86 (84-88), p < .001), Tp-e/QT ratio (0.19 (0.17-0.20); 0.23 (0.22-0.23), p < .001) and Tp-e/QTc ratio (0.17 ± 0.02; 0.21 ± 0.01, p < .001) were higher in group 2 compared to group 1. In multivariate logistic regression analyses Tp-e interval (odds ratio [OR]: 1.315, 95% confidence interval [CI]: 1.203-1.437, p < .001), Tp-e/QT ratio (OR: 7.334, 95% CI: 3.274-1.643, p < .001) and Tp-e/QTc ratio (OR: 2.567, 95% CI: 4.106-1.605, p < .001) were found to be independent predictors of mortality. Additionally, a Kaplan-Meier survival analysis also revealed that long term survival was found to be significantly decreased in patients with higher Tp-e/QT ratio (Log-Rank p < .001) and Tp-e/QTc ratio (Log-Rank p < .001). CONCLUSION: Tp-e interval, Tp-e dispersion, Tp-e/QT, and Tp-e/QTc ratios are associated with worse prognosis after surgical AVR in patients with severe AS. All of them are also independent predictors of mortality.

Influence of disease severity and cardiac autonomic tone on ventricular repolarization and dispersion in electrocardiographic assessment of patients with systemic lupus erythematosus.

BACKGROUND: There are no data on the influence of disease severity and cardiac autonomic tone on ventricular repolarization and dispersion in 24-hour Holter monitoring in systemic lupus erythematosus (SLE). METHODS: Consecutive 92 SLE and 51 healthy subjects were studied. The standard 12-lead electrocardiography (ECG), Holter monitoring with heart rate turbulence (HRT) and QT, Tp-e and Tp-e/QT ratio assessment (including corrected values) were performed. Subjects with conditions causing repolarization abnormalities or insufficient number of beats suitable for QT evaluation were excluded (17 SLE and 8 controls). RESULTS: Finally, 75 SLE and 43 sex- and age-matched controls were included to the study. In SLE patients, the median disease severity score (Systemic Lupus International Collaborating Clinics/American College of Rheumatology Damage Index (SLICC/ACR-DI)) was 3.0. The mean values of QTc, cTp-e and cTp-e/QTc were significantly higher in SLE patients than in controls. QTc ≥ 460 ms was observed in 18.7% of patients using standard ECG and in 58.7% using Holter monitoring. With Holter monitoring, patients with SLICC/ACR-DI >3.0 presented longer QTc than those with SLICC/ACR-DI ≤3.0 (418±15 vs. 409 ± 16, p = 0.04), while cTp-e and cTp-e/QTc values were similar. Patients with abnormal HRT presented longer cTp-e and higher cTp-e/QTc than those with normal HRT (92 ± 52 vs. 71 ± 16 ms, p = 0.04; 0.244 ± 0.126 vs. 0.187 ± 0.035, p = 0.03), while QTc values were similar. No differences in QT and Tp-e parameters were observed according to disease duration. CONCLUSION: In SLE patients, Holter monitoring revealed QTc prolongation more frequently than standard ECG. Longer QTc values were observed in patients with more advanced disease, while increased cTp-e and cTp-e/QTc were related to cardiac autonomic dysfunction expressed by abnormal HRT.

Effects of nicorandil infusion on ECG parameters in patients with unstable angina pectoris and percutaneous coronary intervention.

BACKGROUND: Percutaneous coronary intervention (PCI) is effective in treating patients with acute coronary syndrome (ACS) but is associated with some serious complications. Nicorandil is an anti-anginal agent acting to improve microvascular circulation and to increase coronary blood flow. The objective of this article is to evaluate the effects of intracoronary injection followed with continuous intravenous injection of nicorandil on ECG parameters in patients with unstable angina pectoris (UA) undergoing PCI. METHODS: A single-center, self-controlled clinical trial was conducted at the Second Hospital of Tianjin Medical University between January 2019 and April 2019. Sixty-three consecutive patients with UA who received coronary angiography and selective PCI were enrolled. ECG was recorded and analyzed before and 24 hr after nicorandil infusion. RESULTS: Patients were divided into three groups: control group (n = 23, aged 63.43 ± 12.55 years), short-term, and prolonged use with nicorandil group (n = 20 and 20, aged 66.45 ± 8.06 years and 65.80 ± 9.49 years, respectively). Clinical characteristics and ECG parameters were similar before PCI among three groups (p > .05). In nicorandil treatment groups, intervals of QTd and Tp-e in patients post-PCI were significantly shorter than that in control and pre-PCI (p < .05). CONCLUSIONS: Nicorandil infusion reduces QTd and Tp-e interval in patients with UA. Further studies will be needed to determine whether these electrophysiological changes are associated with a reduction of ventricular arrhythmias and improved outcomes.

The relationship between systolic pulmonary arterial pressure and Tp-e interval, Tp-e/QT, and Tp-e/QTc ratios in patients with newly diagnosed chronic obstructive pulmonary disease.

INTRODUCTION: The risk of sudden cardiac death (SCD) and arrhythmias has been shown to be common in chronic obstructive pulmonary disease (COPD) subjects. We aimed to evaluate the markers of arrhythmia such as QT, QTc (corrected QT), Tp-e, and cTp-e (corrected Tp-e) intervals, Tp-e/QT ratio, and Tp-e/QTc ratio in newly diagnosed COPD subjects in both right and left precordial leads. MATERIALS AND METHODS: The study group consisted of 74 subjects with obstructive respiratory function tests (RFTs). The control group consisted of 78 subjects who had nonobstructive RFTs. RFTs, electrocardiograms (ECG), and transthoracic echocardiograms (TTE) were performed, and QTR (QT interval in right precordial leads), QTL (QT interval in left precordial leads), Tp-eR (Tp-e interval in right precordial leads), and Tp-eL (Tp-e interval in left precordial leads) intervals; systolic pulmonary arterial pressure (sPAP); forced expiratory volume in one second (FEV1 )/forced vital capacity (FVC); and peripheral oxygen saturation(POS) values were measured. RESULTS: Tp-eR interval 85.82 ± 5.34 millisecond (ms) versus 62.87 ± 3.55 ms (t = 31.29/p < .00001), cTp-eR interval 97.51 ± 7.18 ms versus 71.07 ± 4.58 ms (t = 27.20/p < .00001), Tp-eR/QTR ratio 0.234 ± 0.02 versus 0.164 ± 0.01 (t = 2.2/p = .014), and Tp-eR/QTcR ratio 0.201 ± 0.01 versus 0.141 ± 0.01 (t = 1.92/p = .028) were statistically significantly higher in COPD subjects. There was a strong negative correlation between RFT and sPAP (sPAP, 29.93 ± 5.1 mm Hg; and FEV1 /FVC, 63.78 ± 3.33%, r = -.85/p < .00001). There was a moderate positive correlation between sPAP and Tp-eR. CONCLUSION: We found Tp-e and cTp-e intervals, Tp-e/QT ratio, and Tp-e/QTc ratio were significantly higher in the COPD patients than in the control group. In addition, in the COPD group, heart rate variability (HRV) parameters were significantly lower on ECG.

Tp-e interval, Tp-e/QT and Tp-e/QTc ratio in hypertensive patients with primary aldosteronism.

Introduction: There is no study evaluating the Tp-e/QT and Tp-e/QTc ratios with T wave peak to end interval (Tp-e interval) used for evaluation of cardiac arrhythmia risk and ventricular repolarization changes in patients with primary aldosteronism (PA). We aimed to investigate whether there was a change in Tp-e interval, Tp-e/QT and Tp-e/QTc ratios in patients with PA.Method: Thirty patients with newly diagnosed hypertension (HT) and PA and 30 patients with primary HT were included. Twelve-lead electrocardiography (ECG) was performed in all patients. Tp-e interval, Tp-e/QT and Tp-e/QTc ratios were measured in addition to routine measurements in ECG.Results: Sodium, potassium, and plasma renin activity (PRA) were significantly lower in patients with PA; systolic and diastolic blood pressure, plasma aldosterone, plasma aldosterone/PRA were significantly higher in patients with PA (p < .05 for each one). When ventricular repolarization parameters were examined; while QT and QTc interval were similar between two groups, Tp-e interval, Tp-e/QT and Tp-e/QTc ratio values were significantly higher in patients with PA (p < .05 for each one). Tp-e interval, Tp-e/QT and Tp-e/QTc ratio values were positively correlated with the serum calcium, aldosterone, and aldosterone/PRA levels and negatively correlated with serum sodium, potassium, renin levels (p < .05 for each one). In linear regression analyses, Tp-e interval, Tp-e/QT and Tp-e/QTc ratios were independently associated with the aldosterone/PRA ratio.Conclusion: Tp-e interval, Tp-e/QT and Tp-e/QTc were increased in hypertensive patients with PA and were independently associated with aldosterone/PRA levels. This may be related to the changing neuroendocrine state in patients with PA.

Evaluation of the Tp-e interval and Tp-e/QTc ratio in patients with benign paroxysmal positional vertigo in the emergency department compared with the normal population.

INTRODUCTION: Benign paroxysmal positional vertigo (BPPV) is a common diagnosis for dizziness patients admitting to emergency department and for initial diagnosis, cardiac causes of dizziness should be excluded at admittance. Electrocardiography (ECG) is a simple method to detect cardiac arrhythmias for these patients. Tp-e interval and Tp-e/QTc ratio are transmural repolarization parameters and shown to be strongly related to ventricular arrhythmias. With this study, we aim to investigate ventricular repolarization parameters like Tp-e interval and Tp-e/QTc ratio which can be easily evaluated by ECG in BPPV patients. MATERIALS AND METHODS: A total of 84 newly diagnosed BPPV patients and 59 age-sex matched control group without dizziness symptoms compatible with inclusion criteria were included for the study. Patients with previous vertigo, coronary artery disease, renal disease, heart failure, severe valvular disease, arrhythmia history, electrolyte disturbances and patients under 18 years of age were excluded. RESULTS: Mean age of the study population was 44.4 ±â€¯12.1 years, 36.4% were male. There was no significant difference among groups in terms of age, sex, diabetes mellitus, hypertension and hypothyroidism history. When ECG results were evaluated QRS interval, QT interval, Tp-e interval, Tp-e/QT ratio and Tp-e/QTc ratio were statistically higher in BPPV patients compared to control group (p = 0.000, p = 0.047, p = 0.000, p = 0.000 and p = 0.001, respectively). DISCUSSION: As a result of our study, Tp-e and Tp-e/QTc ratio were significantly higher in BPPV patients compared to the control group. These findings suggest that ventricular arrhythmia risk may be higher in BPPV patients. Further evaluation of these patients in terms of ventricular arrhythmia would be beneficial.

Evaluation of electrocardiographic ventricular repolarization variables in patients with newly diagnosed COVID-19.

INTRODUCTION: Coronavirus disease 2019 (COVID-19) is a newly recognized infectious disease that has spread rapidly. COVID-19 has been associated with a number of cardiovascular complications, including arrhythmias. The mechanism of ventricular arrhythmias in patients with COVID-19 is uncertain. The aim of the present study was to evaluate the ventricular repolarization by using the Tp-e interval, QT dispersion, Tp-e/QT ratio, and Tp-e/QTc ratio as candidate markers of ventricular arrhythmias in patients with newly diagnosed COVID-19. In addition, the relationship between the repolarization parameters and the CRP (C-reactive protein) was investigated. METHODS: 75 newly diagnosed COVID-19 patients, 75 age and sex matched healthy subjects were included in the study between 20th March 2020 and 10th April 2020. The risk of ventricular arrhythmias was evaluated by calculating the electrocardiographic Tp-e and QT interval, Tp-e dispersion, corrected QT(QTc), QT dispersion (QTd), corrected QTd, Tp-e/QT and Tp-e/QTc ratios. CRP values were also measured in patients with newly diagnosed COVID-19. RESULTS: Tp-e interval (80.7 ±â€¯4.6 vs. 70.9 ±â€¯4.8; p < .001), Tp-e / QT ratio (0.21 ±â€¯0.01 vs. 0.19 ±â€¯0.01; p < .001) and Tp-e/QTc ratio (0.19 ±â€¯0.01 vs.0.17 ±â€¯0.01; p < .001) were significantly higher in patients with newly diagnosed COVID-19 than the control group. There was a significant positive correlation between Tp-e interval, Tp-e/QTc ratio and CRP in patients with newly diagnosed COVID-19 (rs = 0.332, p = .005, rs = 0.397, p < .001 consecutively). During their treatment with hydroxychloroquine (HCQ), azithromycin and favipiravir, ventricular tachycardia episodes were observed in in two COVID-19 patients during their hospitalization in the intensive care unit. CONCLUSION: Our study showed for the first time in literature that the Tp-e interval, Tp-e/QT ratio, and Tp-e/QTc ratio, which are evaluated electrocardiographically in patients with newly diagnosed COVID-19, were prolonged compared with normal healthy individuals. A positive correlation was determined between repolarization parameters and CRP. We believe that pre-treatment evaluation of repolarization parameters in newly diagnosed COVID-19 would be beneficial for predicting ventricular arrhythmia risk.

Evaluation of Tp-e interval and Tp-e/QT ratio in major burn patients.

INTRODUCTION: Major burn injury is an acute stress reaction with systemic effects. Major burn injury has been associated with a number of cardiovascular dysfunctions, including ventricular arrhythmias. The mechanism of increased ventricular arrhythmias in burn patients uncertain. The aim of the present study was to evaluate the ventricular repolarization by using the Tp-e interval, Tp-e/QT ratio, and Tp-e/QTc ratio as candidate markers of ventricular arrhythmias in patients with major burn patients. In addition, the relationship between the repolarization parameters and the CRP(C-reactive protein) and ABSI(Abbreviated Burn Severity Index) score was investigated. METHODS: 55 major burn patients, 55 age and sex matched healthy subjects were included in the study between January 2017 and September 2019. The risk of ventricular arrhythmias was evaluated by calculating the electrocardiographic Tp-e and QT interval, corrected QT(QTc), Tp-e/QT and Tp-e/QTc ratios. ABSI score was calculated in burn patients. Left ventricular functions were evaluated by echocardiography. RESULTS: Tp-e interval (80.7 ±â€¯5.7 vs. 67.4 ±â€¯5.7; p < 0.001), Tp-e/QT ratio (0.21 ±â€¯0.01 vs. 0.18 ±â€¯0.01; p < 0.001) and Tp-e/QTc ratio (0.20 ±â€¯0.01 vs.0.17 ±â€¯0.01; p < 0.001) were significantly higher in major burn patients than the control group. There was a significant positive correlation between Tp-e interval, Tp-e/QTc ratio and ABSI score in major burn patients (r = 0.870, p < 0.001, r = 0.312, p = 0.020 consecutively). CONCLUSION: Our study showed for the first time in literature that the Tp-e interval, Tp-e/QT ratio, and Tp-e/QTc ratio, which were evaluated electrocardiographically in major burn patients, were prolonged compared with normal healthy individuals. A positive correlation was determined between repolarization parameters and ABSI score. Whether these changes increase the risk of ventricular arrhythmia deserve further studies. TAKE-HOME MESSAGE: Tp-e interval, Tp-e/QT ratio, and Tp-e/QTc ratio, which were evaluated electrocardiographically in major burn patients, were prolonged compared with normal healthy individuals and a positive correlation was found between these repolarization parameters and burn severity.