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.

QTc, Tp-e Interval and Tp-e/QTc Ratio in Patients with Hypocalcemia-case Control Study

Abstract Background: To the best of our knowledge, there are studies related to QT and QTc interval in patients with hypocalcemia, but there are no studies evaluating T wave peak and end interval (Tp-e interval), Tp-e/QT and Tp-e/QTc ratios used to evaluate cardiac arrhythmia risk and ventricular repolarization changes rates. Objectives: Therefore, we aimed to investigate whether there is a change in Tp-e interval, Tp-e/QT and Tp-e/QTc ratios in patients with hypocalcemia. Methods: Retrospectively, 29 patients with hypocalcemia in the emergency department were included in the study. Twenty-nine patients with similar age and sex distribution were included in the study as the control group. All patients underwent 12-lead electrocardiography (ECG). In addition to routine measurements, Tp-e interval, Tp-e/QT and Tp-e/QTc ratios were measured on ECG. The study data were grouped as patients with and without hypocalcemia. Results: The mean age of the patients was 66.24 ± 4.95 years. QTc interval, Tp-e interval and Tp-e/QTc values were found to be significantly higher in patients with hypocalcemia (p <0.001 for each). QTc interval, Tp-e interval and Tp-e/QTc ratio showed a significant negative correlation with calcium levels. Conclusion: Tp-e interval and Tp-e/QTc ratios are significantly increased in patients with hypocalcemia compared to those without hypocalcemia and this can be used more effectively in the follow-up of cardiac fatal arrhythmias.

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.

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.

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.

Relationship With Calcium, Nutrition Risk, QTc Interval, Tp-e Interval, and Tp-e/QTc Ratio of Critical Care Patients.

BACKGROUND: To our knowledge, there are studies related to QTc interval in critical care patients whose nutrition scores are evaluated but no studies evaluating T-wave peak and end interval (Tp-e interval), Tp-e/QT ratio, and Tp-e/QTc ratio, used to evaluate cardiac arrhythmia risk and ventricular repolarization change rates. Therefore, we aimed to investigate whether there is a change in Tp-e interval, Tp-e/QT ratio, and Tp-e/QTc ratio in patients whose nutrition scores are evaluated. METHODS: This study was planned as a retrospective cross-sectional study. Forty-four patients with a risk score of ≤3 were defined as low-risk group, and 45 patients with a score of ≥4 were defined as high-risk group. Forty-five healthy patients of similar age and gender were included in the control group. All patients underwent 12-lead electrocardiography (ECG). The Tp-e interval, Tp-e/QT ratio, and Tp-e/QTc ratio were measured on ECG. The study data were grouped as patients with high Nutritional Risk Screening 2002 (NRS-2002) risk score, low NRS-2002 risk score, and healthy control. RESULTS: QTc interval, Tp-e interval, and Tp-e/QTc ratios were significantly higher in patients with high nutrition risk. In a correlation analysis, Tp-e interval and Tp-e/QTc ratio were found to be independently associated with calcium, corrected calcium, and serum albumin level. CONCLUSION: QTc interval, Tp-e interval, and Tp-e/QTc ratios are significantly increased in patients with high nutrition risk score compared with healthy people and are independently associated with calcium and serum albumin levels; thus, they can be used more effectively in the follow-up of cardiac fatal arrhythmias.

Impaired repolarization parameters may predict fatal ventricular arrhythmias in patients with hypertrophic cardiomyopathy (from the CILICIA Registry).

BACKGROUND: Hypertrophic cardiomyopathy (HCM) is significantly associated with high risk of fatal ventricular arrhythmias (VAs). Increased frontal QRST angle (fQRSTa), Tpe interval, and Tp-e/QTc ratio are described as ventricular repolarization parameters which are related to arrhythmias. In this study, we aimed to investigate the predictive value of these repolarization parameters for fatal VAs in patients with HCM. METHODS: A total of 127 HCM patients (mean age: 47.9 ±â€¯12.6 years; male:79) were enrolled in this retrospective study. All patients underwent transthoracic echocardiography. Moreover, the last electrocardiograms within 3 months prior to the fatal VA documentation were assessed. The primary outcome was the occurrence of fatal VAs including sustained ventricular tachycardia and ventricular fibrillation which were documented from implantable cardioverter defibrillator records. RESULTS: There were documented fatal VAs in 37 (29.1%) patients during a mean follow-up time of 70.1 ±â€¯22.6 months. The prevalence of fatal VAs was significantly higher in patients with fQRSTa ≥140 degrees (67.4 vs. 7.4%; p < 0.001) and in patients with Tp-e/QTc ratio ≥ 0.19 (61.5 vs. 6.7%; p < 0.001) as compared to others. High Tp-e/QTc ratio (hazard ratio: 1.564; 95% confidence interval: 1.086-4.796; p = 0.032) and high fQRSTa (hazard ratio: 1.864; 95% confidence interval: 1.106-8.745; p = 0.002) were found to be independent predictors of fatal VAs in HCM patients. CONCLUSIONS: Wider fQRSTa, prolonged Tp-e interval, and increased Tp-e/QTc ratio may be associated with fatal VAs in HCM patients. In addition to traditional risk factors, these simple ECG parameters may provide valuable information during evaluation of sudden cardiac death risk in HCM patients.

Diabetic microvascular complications associated with myocardial repolarization heterogeneity evaluated by Tp-e interval and Tp-e/QTc ratio.

INTRODUCTION: The heterogeneity in myocardial repolarization increases the risk of ventricular arrhythmias and sudden death in patients with diabetes mellitus (DM). The Tp-e interval and Tp-e/QTc ratio are found to be useful in the prediction of ventricular arrhythmias. In this study, we aimed to investigate the Tp-e interval and Tp-e/QTc ratio in diabetic patients with and without microvascular complications. MATERIALS AND METHODS: This cross-sectional observational study included patients with type 2 DM who presented to the endocrinology outpatient clinic. Diabetic microvascular complications were evaluated. The Tp-e interval, Tp-e/QT ratio, and Tp-e/QTc ratio were also calculated. RESULTS: A total of 240 patients with type 2 DM (148 patients had microvascular complications) were included in the study. Diabetic neuropathy rate was 30.4%, diabetic nephropathy rate was 38.4%, and diabetic retinopathy rate was 21.7%. Upon comparing patients according to Tp-e/QTc ratio, the median Tp-e/QTc interval of the group of patients with complications was 0.21 (0.19-0.23) and the median Tp-e/QTc ratio of the group of patients without complications was 0.19 (0.18-0.20) (p < 0.001). When patients were grouped according to the presence and severity of retinopathy, the Tp-e/QTc ratio was more prolonged in the proliferative retinopathy group [0.27 (0.23-0.30)] than the non-proliferative retinopathy group [0.20 (0.19-0.22), p < 0.001]. When patients were grouped according to the presence and severity of nephropathy, the Tp-e/QTc ratio was more prolonged in the macroalbuminuria and microalbuminuria group than the normoalbuminuric group [0.25 (0.21-0.30), 0.23 (0.19-0.24), and 0.19 (0.20-0.22), respectively, p = 0.002]. CONCLUSIONS: Our study is the first to demonstrate the association of the Tp-e interval and Tp-e/QTc ratio with the presence and severity of microvascular complications in patients with type 2 DM.

Variation of Tpeak-end, corrected Tpeak-end, QT, and corrected QT intervals, Tpeak-end/QT, Tpeak-end/corrected QT ratios and heart rate variability according to decades in the healthy male subjects aged between 30 and 79 years.

BACKGROUND: Heart rate variability (HRV) is a predictor of cardiac autonomic functions. Ventricular repolarization markers can indicate ventricular arrhythmias. We aimed to evaluate variations of HRV and these repolarization markers in five healthy male groups between age 30 and 79 years according to decades. MATERIALS AND METHODS: The study group consisted of 500 healthy male subjects between October 2018 and May 2019. The male subjects were divided into five categories according to their ages. Then, electrocardiograms (ECG), transthoracic echocardiograms (TTE), and treadmill exercise test (TET) were performed. T-wave peak-end (Tp-e) interval was defined as the time between the peak point and end of T-wave. Tp-e, corrected Tp-e (cTp-e), QT, and corrected QT (QTc) were measured from the resting ECGs and HRV temporal parameters (SDNN, SDNN Index, SDANN Index, RMSSD, sNN50, and pNN50), and HRV frequency parameters (VLF, LF, HF, and LF/HF) were obtained from 24-hour Holter monitorization recordings. One-way ANOVA test was used for the differences between the groups. Pearson correlation test was used to determine the correlations between the values of all groups. RESULTS: Considering the repolarization parameters, there are significant differences in five groups in terms of Tp-e interval, but not Tp-e/QT and Tp-e/QTc ratios. Considering the HRV parameters, there were statistically significant differences between the five male healthy groups in terms of HRV temporal parameters and there are no significant differences in terms of HRV frequency parameters. CONCLUSION: As the age increases, basal Tp-e interval increases and HRV temporal parameters decrease significantly in the male subjects aged between 30 and 79 years, but HRV frequency parameters do not change.

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.

Switching from ramipril to sacubitril/valsartan favorably alters electrocardiographic indices of ventricular repolarization in heart failure with reduced ejection fraction.

Background: Angiotensin receptor neprilysin inhibitor (ARNI, sacubitril/valsartan) reduces sudden death in heart failure with reduced ejection fraction (HFrEF). Corrected QT (QTc), T-wave peak to T-wave end interval (Tp-e) and Tp-e/QTc are electrocardiographic indices of ventricular repolarization heterogeneity. We aimed to assess the effects of switching from ramipril to ARNI on electrocardiographic indices of ventricular repolarization.Methods: A total of 48 patients with HFrEF (mean age: 63.3 ± 11.7 years; 36 males, 77.1% ischaemic etiology) were enrolled. All patients had New York Heart Association functional class II-III, left ventricular ejection fraction ≤35% and previously switched from ramipril to ARNI treatment. The standard 12-lead electrocardiograms on ramipril treatment and 1 month after ARNI treatment were analysed; heart rate, QTc, Tp-e and Tp-e/QTc were calculated. Minnesota Living with Heart Failure Questionnaire (MLWHFQ) scores and N-terminal pro-BNP (NT-proBNP) values were recorded.Results: QTc (415.2 ± 19.7 ms vs. 408.5 ± 20.8 ms, p = 0.022), Tp-e (100.7 ± 13.8 ms vs. 92.9 ± 12.1 ms, p < 0.001), Tp-e/QTc (0.242 ± 0.028 vs. 0.227 ± 0.029, p = 0.003) and heart rate (73.2 ± 4.7 bpm vs. 71.1 ± 4.9 bpm, p = 0.027) were reduced after ARNI. ARNI switch associated with improvement in MLWHFQ scores (32.4 ± 7.1 ms vs. 22.6 ± 7.0 ms, p < 0.001) and reduction of NT-proBNP (2457 ± 1879 pg/ml to 1377 ± 874 pg/ml, p < 0.001). Pearson's correlation analysis revealed moderate correlations of MLWHFQ score with Tp-e (r = 0.543, p = 0.001) and Tp-e/QTc (r = 0.556, p = 0.001).Conclusions: Switching from ramipril to ARNI favourably alters QTc, Tp-e and Tp-e/QTc in HFREF. ARNI reduces symptoms of HFREF assessed by MLWHFQ and lowers NT-proBNP levels. Reduction in Tp-e and Tp-e/QTc correlate with clinical improvement in patients with HFrEF.

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 parameters in extreme obesity.

BACKGROUND AND OBJECTIVES: The risk of sudden death and cardiac arrhythmia increases in morbidly obese patients. We aimed to evaluate the marker of arrhythmias such as Tp-e/QT, Tp-e/QTc, Tp-e/JT and Tp-e/JTc ratios in extreme obesity. METHODS: The study included 41 extremely obese patients and 41 control subjects. QTmax, QTmin, QRS, JT and Tp-e intervals were measured od 12­lead electrocardiographies. In addition, Tp-e/QT, Tp-e/QTc, Tp-e/JT and Tp-e/JTc rates and QTc, cQTd and JTc intervals were calculated. RESULTS: Tp-e interval (79.2 ±â€¯9.7 ms (milisecond) vs. 68.6 ±â€¯8.1, p < 0.001), QTc interval (395.9 ±â€¯18.8 vs. 377.9 ±â€¯19.3 ms, p < 0.001), JTc interval (317.1 ±â€¯27.0 vs. 297.4 ±â€¯23.2 ms, p = 0.001), Tp-e/QT ratio (0.22 ±â€¯0.03vs. 0.19 ±â€¯0.02, p < 0.001), Tp-e/QTc ratio (0.20 ±â€¯0.26vs. 0.18 ±â€¯0.02, p = 0.001), Tp-e/JT ratio (0.29 ±â€¯0.04 vs. 0.25 ±â€¯0.03, p < 0.001), TPe/JTc ratio (0.25 ±â€¯0.04 vs. 0.23 ±â€¯0.03, p = 0.018), QTd (32.8 ±â€¯10 vs.15 ±â€¯6.4 ms, p < 0.001) and cQTd (70.0 ±â€¯30.1 vs. 31.3 ±â€¯22.4 ms, p < 0.001) were significantly higher in obese patients. CONCLUSION: Compared to healthy subjects potential ECG repolarization predictors were significantly increased in extremely obese patients.

Evaluation of myocardial dispersion of repolarization in patients with heart transplantation

Background/aim: The number of patients with heart transplantation has dramatically increased in the last decade. Considerable studies have suggested that the interval from the peak to the end of the electrocardiographic T wave (Tp-e) may correspond to the transmural dispersion of repolarization and increased Tp-e interval and Tp-e/QT ratio are associated with malignant ventricular arrhythmias. We analyzed the dispersion of myocardial repolarization using electrocardiographic Tp-e interval and Tp-e/QTc ratio in patients with heart transplantation. Materials and methods: This observational study included 38 patients (12 female and 26 male) with heart transplantation and 38 well-matched controls. From electrocardiograms, Tp-e interval and Tp-e/QTc ratio were calculated and compared between the 2 groups. Results: Noninvasive arrhythmia indicators including Tp-e interval (84.63 ± 14.17 ms vs 71.82 ± 7.47 ms, P < 0.001), Tp-e/QTc ratio (0.19 ± 0.04 vs 0.16 ± 0.02, P < 0.001) and QTc interval except QT interval were significantly higher in transplanted hearts compared to normal hearts. Conclusion: Patients with heart transplantation have increased myocardial dispersion of repolarization.

Prolonged T-wave peak-end interval in Down syndrome patients with congenitally normal hearts.

BACKGROUND: Heterogeneity of ventricular repolarization has been assessed using the QT dispersion in Down syndrome (DS) patients with congenitally normal hearts. Novel repolarization indexes, that is, T-wave peak-end (Tp-e) interval and Tp-e/QT ratio, however, have not previously been evaluated in these patients. The aim of this study was therefore to evaluate the Tp-e interval and Tp-e/QT ratio in DS patients without congenital heart defects. METHODS: Tp-e interval, Tp-e dispersion, and Tp-e/QT ratio were compared between 160 DS patients and 110 age- and sex-matched healthy controls on 12-lead surface electrocardiogram. RESULTS: Heart rate, Tp-e interval, Tp-e dispersion, Tp-e/QT and Tp-e/QTc ratios were significantly higher in the DS group than the control group. CONCLUSION: Myocardial repolarization indexes in DS patients with congenitally normal hearts were found to be prolonged compared with those in normal controls. Further evaluation is warranted to elucidate the relationship between prolonged repolarization indexes and arrhythmic events in these patients.

Evaluation of Tp-e interval, Tp-e/QT ratio and Tp-e/QTc ratio in patients with subclinical hypothyroidism.

BACKGROUND: Prolongation of the peak-to-end interval of the T wave (Tp-e) has been reported as associated with ventricular arrhythmias. The aim of this study was to investigate the ventricular repolarization by using the Tp-e interval, Tp-e/QT ratio and Tp-e/ QTc ratio in patients with subclinical hypothyroidism (SH). METHODS: We studied 56 volunteers: These were 28 patients with SH (mean age 45 ± 11 years) and 28 healthy subjects (mean age 34 ± 8 years). All basic biochemical parameters were analyzed and electrocardiograms (ECGs) were recorded. RR and QT intervals, QTc, Tp-e intervals and the Tp-e/QT and Tp-e/QTc ratios were calculated. The categorical and numerical variables were compared using the chi-square test and independent t test, respectively. Correlations were analyzed using the Spearman and Pearson correlation tests. RESULTS: We found no difference between QT and QTc intervals between groups. In the subjects with SH, the Tp-e intervals (87 ± 5 ms, 66 ± 5 ms, p< 0.01), Tp-e/ QT ratio (0.23 ± 0.03, 0.18 ± 0.01, p< 0.01) and Tp-e/QTc ratio (0.21 ± 0.02, 0.16 ± 0.01, p< 0.01) were increased compared with healthy subjects. We also found positive correlations between levels of thyroid stimulating hormone (TSH) and Tp-e (r = 0.72, p< 0.01), Tp-e/ QT ratio (r = 0.67 p< 0.01), Tp-e/ QTc ratio (r = 0.68, p< 0.01). In the subjects with SH, Left Ventricular Myocardial Performance Index (LV-MPI) was increased compared with the healthy subjects (0.64 ± 0.08, 0.59 ± 0.09, p = 0.066) although it was not significant. CONCLUSIONS: Compared with healthy subjects, patients with SH demonstrated longer Tp-e intervals, and higher Tp-e/QT and Tp-e/QTc ratios. TSH levels were positively correlated with Tp-e interval, Tp-e/QT ratio, and Tp-e/QTc ratio.

Tp-e Interval, Tp-e/QTc Ratio, and Fragmented QRS Are Correlated with the Severity of Liver Cirrhosis.

BACKGROUND: Arrhythmias and electrocardiographic changes are reported in several noncardiac diseases, including liver cirrhosis (LC). We intended to evaluate the interval from the peak to the end of the electrocardiographic T wave (Tp-e), Tp-e/QTc ratio, and fQRS as presumed markers of arrhythmias in LC. METHODS: In this cross-sectional study, a total of 88 consecutive patients with LC according to clinical, biological, ultrasonographic, or histological criteria and 73 control subjects were enrolled. The severity of cirrhosis was classified according to Pugh-Child's classification and Model for End-Stage Liver Disease (MELD) score. Tp-e interval, Tp-e/QTc ratio, and fQRS rates were measured from the 12-lead electrocardiogram. RESULTS: Tp-e interval, Tp-e/QTc ratio and fQRS rates were significantly increased in parallel to the severity of LC (P < 0.001, P < 0.001, and P = 0.003, respectively). In correlation analysis, Pugh-Child stage showed a significantly positive correlation with Tp-e interval (r = 0.462, P < 0.001), QTc interval (r = 0.373, P < 0.001), Tp-e/QTc ratio (r = 0.352, P < 0.001), and fQRS (r = 0.407, P < 0.001). Furthermore, Tp-e interval (r = 0.414, P < 0.001) and Tp-e/QTc ratio (r = 0.426, P< 0.001) had significant positive correlation with MELD score. CONCLUSIONS: Our study demonstrated that Tp-e interval, Tp-e/QTc ratios, and fQRS rates were significantly increased in parallel to the severity of LC. Thus, these findings may implicate that Tp-e interval, Tp-e/QTc ratio, and fQRS may be novel and useful indicators for prediction of arrhythmias in LC.

Prolonged Tp-e Interval and Tp-e/QT Ratio in Children with Mitral Valve Prolapse.

Although it is considered to be a benign condition, previous studies have shown that a subset of patients with mitral valve prolapse (MVP) may be at risk of ventricular arrhythmia and sudden cardiac death (SCD). Previous studies have suggested that the interval between the peak and the end of the T wave (Tp-e) can be used as a marker for the transmural dispersion of repolarization. Increased Tp-e interval and Tp-e/QT ratio are associated with ventricular arrhythmias and SCD. The aim of this study was to assess alterations in ventricular repolarization by using the Tp-e interval and Tp-e/QT ratio in children with MVP and to investigate their relationships with the degree of valvular regurgitation. This study prospectively investigated 110 children with MVP and 107 age- and sex-matched healthy control subjects. Tp-e interval, Tp-e/QT ratio, and QT and QTc dispersions were measured from a 12-lead electrocardiogram and compared between groups. QT and QTc dispersions, Tp-e interval, and Tp-e/QTc ratio were found to be significantly higher in patients with MVP. A positive correlation was found between Tp-e/QTc ratio and increase in the degree of mitral regurgitation (MR) (p < 0.05; r = 0.2). However, the degree of MR was not associated with QT, QTc, or Tp-e intervals; QT, QTc, or Tp-e dispersions; or Tp-e/QT ratio (all p values >0.05). Individuals with MVP may be more prone to ventricular arrhythmias due to prolonged QTd, QTcd, and Tp-e interval and increased Tp-e/QT and Tp-e/QTc ratios. Therefore, due to their longer life expectancy, children with MVP should be followed up on regarding life-threatening arrhythmias.