Can the T-peak to T-end interval be a predictor of mortality in patients with ST-elevation myocardial infarction?

A Longer Tpeak-Tend Interval Is Associated with a Higher Risk of Death: A Meta-Analysis

A noninvasive tool for cardiovascular risk stratification has not yet been established in the clinical routine analysis. Previous studies suggest a prolonged T_peak-T_end interval (the interval from the peak to the end of the T-wave) to be predictive of death. This meta-analysis was designed to systematically evaluate the association of the T_peak-T_end interval with mortality outcomes. Medline (via PubMed), Embase and the Cochrane Library were searched from 1 January 2008 to 21 July 2020 for articles reporting the ascertainment of the T_peak-T_end interval and observation of all-cause-mortality. The search yielded 1920 citations, of which 133 full-texts were retrieved and 29 observational studies involving 23,114 patients met the final criteria. All-cause deaths had longer T_peak-T_end intervals compared to survivors by a standardized mean difference of 0.41 (95% CI 0.23-0.58) and patients with a long T_peak-T_end interval had a higher risk of all-cause death compared to patients with a short T_peak-T_end interval by an overall odds ratio of 2.33 (95% CI 1.57-3.45). Heart rate correction, electrocardiographic (ECG) measurement methods and the selection of ECG leads were major sources of heterogeneity. Subgroup analyses revealed that heart rate correction did not affect the association of the T_peak-T_end interval with mortality outcomes, whereas this finding was not evident in all measurement methods. The T_peak-T_end interval was found to be significantly associated with all-cause mortality. Further studies are warranted to confirm the prognostic value of the T_peak-T_end interval.

The relationship between length of stay in intensive care unit and Tpeak‐Tend and Tpeak‐Tend/QTc ratio in COVID 19 patients with acute coronary syndrome

Background

Patients with coronavirus disease 2019 (COVID‐19) can develop cardiac injury resulting in cardiac arrhythmias, myocarditis, and acute coronary syndrome (ACS). In this study, we aimed to investigate whether COVID‐19 infection affects ventricular repolarization parameters such as Tpeak‐Tend interval (Tp‐e), QT interval, corrected QT (QTc), Tp‐e/QT, and Tp‐e/cQT in patients with ACS.

Methods

The study consisted of two groups. The first group included patients with ACS and COVID‐19 (Group 1) (n = 50). Polymerase chain reaction test positive patients were enrolled. The second group included patients with only ACS (Group 2) (n = 100). The risk of ventricular arrhythmias was evaluated on the basis of the measured electrocardiographic Tp‐e and QT interval, and QTc, Tp‐e/QT, and Tp‐e/QTc values.

Results

Tp‐e interval, QTc, and Tp‐e/QTc were significantly higher in the group1 than group 2 (p < .001, p < .018, and p < .001, respectively). Significant positive correlations were found between Tp‐e, D‐dimer level, and C‐reactive protein (CRP) level in the group1 (p = .002, p = 0 .03, and p = .021, respectively). Univariate and multivariate regression analyses revealed that Tp‐e was one of the independent predictor of length of stay in the intensive care unit (ICU). (B = 1.662, p = .006 and B = 1.804, p = .021, respectively).

Conclusions

In the patients with ACS, COVID‐19 infection caused increases in QTc, Tp‐e, and Tp‐e/QTc ratio. In addition, age and prolonged Tp‐e were found to be independent predictors of prolonged ICU stay.

The association between QTc, QTd, TPE, and fragmented QRS before and after PPCI with hospital mortality in STEMI patients

INTRODUCTION

ST-elevation myocardial infarction (STEMI) is known to be associated with significant arrhythmia and consequent mortality. QT prolongation is a risk factor for arrhythmia in STEMI patients who underwent primary percutaneous coronary intervention (PPCI). The aim of this investigation was to evaluate the association of corrected QT interval (QTc), QT dispersion (QTd), T-wave peak to end (TPE), and fragmented QRS with mortality in these patients.

METHODS

Eligible patients with the characteristic symptoms of STEMI who underwent PPCI were included. QTc, QTd, TPE, and fragmented QRS were measured before and after the PPCI. These predictors were compared between patients who died during hospitalization and discharged patients.

RESULTS

After coronary angiography, 10 patients (4%) died during the hospitalization after PPCI. Comparing the non-survivers and discharged patients in terms of arrhythmia predictors showed that the mean QT dispersion and TPE before intervention were significantly higher in the non-survivors. Also, the number of patients who experienced fragmented QRS both before and after the intervention was significantly higher in the non-survivors.

CONCLUSION

These data suggested that evaluating such arrhythmia predictors, especially before PPCI, could be used as a predictor of mortality in STEMI patients who underwent PPCI.

Correlation between frontal QRS‐T angle, Tp‐e interval, and Tp‐e/ QT ratio to coronary artery severity assessed with SYNTAX score in stable coronary artery disease patients

Background

Methods

Results

Conclusions

Prognostic value of infarct-related-lead Tpeak-Tend/QT ratio in patients with ST-segment elevation myocardial infarction

Tpeak-Tend/QT ratio (Tp-e/QT) in patients with ST-segment elevation myocardial infarction (STEMI) is reportedly associated with major adverse cardiac events (MACEs). However, Tp-e/QT measurement methods are controversial, and few studies have clarified the effect of different Tp-e/QT measures on prognosis. Our study is the first to investigate the advantages of the Tp-e/QT measured by infarct-related-lead method in predicting MACEs during hospitalization and long-term mortality in patients with STEMI. A total of 427 STEMI patients undergoing primary percutaneous coronary intervention (PCI) were included in this study. The Tp-e/QT before PCI was measured by traditional 12-lead method and infarct-related-lead method. Outcomes were tested using comparative statistics, logistic regression, receiver operating characteristic (ROC) curve and Kaplan-Meier survival analysis. There were 62 (14.5%) patients who had MACEs in-hospital. Logistic regression showed that the Tp-e/QT in infarct-related-lead was an independent predictor (p < 0.001). The area under the ROC curve (AUC) of the Tp-e/QT in infarct-related-lead was larger than that in the Tp-e/QT in traditional 12-lead (0.889 vs 0.741), and the optimal cutoff value was 0.32. The three-year survival rate of patients in the infarct-related-lead Tp-e/QT < 0.32 group was better than Tp-e/QT ≥ 0.32 group in Kaplan-Meier survival analysis (93.9 vs 87.0%). When stratified according to infarct-related arteries, the results showed that the common odds ratio of patients in Tp-e/QT ≥ 0.32 group occurred MACEs was 1.562, P = 0.038. The infarct-related-lead Tp-e/QT performed better than the traditional 12-lead Tp-e/QT in predicting poor prognosis.

In-Hospital Prognostic Value of Electrocardiographic Parameters Other Than ST-Segment Changes in Acute Myocardial Infarction: Literature Review and Future Perspectives

Electrocardiography (ECG) remains an irreplaceable tool in the management of the patients with myocardial infarction, with evaluation of the QRS and ST segment being the present major focus. Several ECG parameters have already been proposed to have prognostic value with regard to both in-hospital and long-term follow-up of patients. In this review, we discuss various ECG parameters other than ST segment changes, particularly with regard to their in-hospital prognostic importance. Our review not only evaluates the prognostic segments and parts of ECG, but also highlights the need for an integrative approach in big data to re-assess the parameters reported to predict in-hospital prognosis. The evolving importance of artificial intelligence in evaluation of ECG, particularly with regard to predicting prognosis, and the potential integration with other patient characteristics to predict prognosis, are discussed.

Assessment of the relationship between reperfusion success and T-peak to T-end interval in patients with ST elevation myocardial infarction treated with percutaneous coronary intervention

Objective:

T-peak–T-end (TPE) interval, which represents the dispersion of repolarization, is defined as the interval between the peak and end of the T-wave, and is associated with increased malignant ventricular arrhythmia and sudden cardiac death (SCD) in patients with ST elevation myocardial infarction (STEMI). Although prolonged TPE interval is associated with poor short- and long-term outcomes, even in patients with STEMI treated with successful primary percutaneous coronary intervention (pPCI), clinical, angiographic, and laboratory parameters that affect TPE remain to be elucidated. The aim of our study was to evaluate the potential relationship between prolonged TPE interval and reperfusion success using ST segment resolution (STR) in patients with STEMI undergoing pPCI.

Methods:

In the current study, 218 consecutive patients with STEMI who underwent pPCI were enrolled; after exclusion, 164 patients were included in the study population.

Results:

Patients were divided into two groups according to the presence of complete (STR%≥70) or incomplete (STR%<70) STR. Preprocedural corrected TPE (cTPE_PRE;116±21 ms vs. 108±21 ms; p=0.027), postprocedural TPE (TPE_POST; 107±16 ms vs. 92±21 ms; p<0.001), and postprocedural cTPE (cTPE_POST; 119±19 ms vs. 102±17 ms; p<0.001) intervals were significantly longer in patients with incomplete STR than in patients with complete STR, whereas there was no statistically significant difference between the two groups in terms of pre- and postprocedural and corrected QT intervals. cTPE_PRE and cTPE_POST were found to be independent predictors for incomplete STR.

Conclusion:

To our knowledge, this is the first study that evaluated the relationship between TPE interval and no-reflow defined by STR in patients with STEMI who were treated with pPCI.

Electrocardiographic measures of ventricular repolarization dispersion and arrhythmic outcomes among ST elevation myocardial infarction patients with pre-infarction angina undergoing primary percutaneous coronary intervention

BACKGROUND

Arrhythmias are considered one of the major causes of death in ST elevation myocardial infarction (STEMI), particularly in the early in-hospital phase. Pre-infarction angina (PIA) has been suggested to have a protective role.

OBJECTIVES

To study the difference in acute electrocardiographic findings between STEMI patients with and without PIA and to assess the in-hospital arrhythmias in both groups.

MATERIAL AND METHODS

We prospectively enrolled 238 consecutive patients with STEMI. Patients were divided into two groups: those with or without PIA. ECG data recorded and analyzed included ST-segment resolution (STR) at 90 min, corrected QT interval (QTc) and dispersion (QTD), T-peak-to-T-end interval (Tp-Te), and dispersion and Tp-Te/QT ratio. In-hospital ventricular arrhythmias encountered in both groups were recorded. Predictors of in-hospital arrhythmias were assessed among different clinical and electrocardiographic parameters.

RESULTS

Of the 238 patients included, 42 (17%) had PIA and 196 (83%) had no PIA. Patients with PIA had higher rates of STR (p < 0.0001), while patients with no PIA had higher values of QTc (p = 0.006), QTD (p = 0.001), Tp-Te interval (p = 0.001), Tp-Te dispersion (p < 0.0001), and Tp-Te/QT ratio (p = 0.01) compared to those with angina preceding their incident infarction (PIA). This was reflected into significantly higher rates of in-hospital arrhythmias among patients with no PIA (20% vs. 7%, p = 0.04). Furthermore, longer Tp-Te interval and higher Tp-Te/QT ratio independently predicted in-hospital ventricular arrhythmias.

CONCLUSION

Pre-infarction angina patients had better electrocardiographic measures of repolarization dispersion and encountered significantly less arrhythmic events compared to patients who did not experience PIA.

Evaluation of ventricular repolarization parameters during migraine attacks

AIMS

Migraine is a chronic neurovascular disorder characterized by intermittent episodes of severe headache. Abnormalities in the autonomic nervous system (sympathetic and parasympathetic nervous systems) have been detected during migraine-free periods in patients with migraine. In these patients, disrupted autonomic innervations of the heart and coronary arteries may lead to electrocardiographic changes during a migraine attack. T-wave peak-to-end interval (Tp-e interval) and Tp-e/QT ratio are relatively new markers of ventricular arrhythmogenesis and repolarization heterogeneity. In the present observational study, we investigated the changes in ventricular repolarization during migraine attacks and attack-free periods by performing 12‑lead electrocardiography (ECG).

METHODS

This study included 63 patients (54 [86%] women; mean age: 33.3 ± 9.9 years) with migraine. The QT and corrected QT (QTc) intervals, Tp-e interval, and Tp-e/QT ratio of the patients during migraine attacks and attack-free periods were measured by performing 12‑lead ECG.

RESULTS

The QT and QTc intervals, Tp-e interval, and Tp-e/QT ratio were higher during migraine attacks than during attack-free periods (P < 0.001 for all).

CONCLUSION

These results indicate that migraine attacks are associated with an increase in ventricular repolarization parameters compared with attack-free periods possibly because of the dysregulation of the autonomic nervous system.

Tpeak-Tend/QT interval predicts ST-segment resolution and major adverse cardiac events in acute ST-segment elevation myocardial infarction patients undergoing percutaneous coronary intervention

Elevated ST-segment and increased Tpeak-Tend interval (Tp-e) were prognostic predictors in major adverse cardiac events (MACEs) in ST-segment elevation myocardial infarction (STEMI). The electrophysiologic relationship between them during percutaneous coronary intervention (PCI) needs to elucidate.Patients with STEMI admitted to hospital were prospectively evaluated. ST-segment resolution (STR) (defined as ≥50% reduction as the complete-STR [CSTR] group, <50% as incomplete-STR [ISTR] group), Tp-e interval, and ratio of Tp-e to QT interval (Tp-e/QT) were measured, calculated and analyzed with MACEs.Tp-ec interval (corrected Tp-e interval, P < .001) and Tp-e/QT ratio (P < .001) were significantly increased by myocardial infarction and partly recovered post-PCI. Patients with ISTR showed more increased Tp-ec interval (P < .001) and Tp-e/QT ratio (P < .001) than those in CSTR groups post-PCI. In multivariate analysis and receiver operating characteristic curves analysis, Tp-e/QT was an independent and strongest predictor for STR. STR and electrocardiogram parameters with a cutoff value for predicting STR showed prognostic value for MACE in STEMI in Kaplan-Meier survival analysis.Both STR and change of Tp-e parameters were not only predictors of arrhythmia, but also prognostic factors of MACE in patients with STEMI after PCI.

Is There any Relationship Between Myocardial Repolarization Parameters and the Frequency of Ventricular Premature Contractions?

BACKGROUND

Ventricular premature contractions (VPCs) may trigger lethal ventricular arrhythmias in patients with structural heart disease. However, this role of VPCs in healthy people remains controversial once that not enough clinical trials are available. Recently, some myocardial repolarization markers, such as Tp-e interval, Tp-e/QT, and Tp-e/QTc ratios, have been reported to be useful for predicting lethal ventricular arrhythmias in various clinical disorders without structural heart disease.

OBJECTIVE

In this study, we aimed to investigate the relation between VPC frequent and myocardial repolarization markers in individuals without structural heart disease.

METHODS

This study included 100 patients who had complaints of dizziness and palpitations. Twelve-lead electrocardiography and 24-hour ambulatory Holter recordings were obtained from all patients. VPC burden was calculated as the total number of VPCs divided by the number of all QRS complexes in the total recording time. P-values < 0.05 were considered significant.

RESULTS

Tp-e interval and Tp-e/QTc ratio were significantly higher in patients with higher VPC burden than in patients with lower VPC burden, and a positive correlation was found between these markers and VPC burden. Tp-e (β = 1.318, p = 0.043) and Tp-e/QTc (β = -405.136, p = 0.024) in the lead V5 were identified as independent predictors of increased VPC burden.

CONCLUSIONS

Tp-e interval and Tp-e/QTc ratio increased in patients with high VPC number. Our study showed that VPCs may have a negative effect on myocardial repolarization. This interaction may lead to an increased risk of malignant arrhythmias.

Myocardial repolarization is affected in patients with ascending aortic aneurysm

OBJECTIVE

Ascending aortic aneurysm (AAA) is one of the major causes of ventricular diastolic dysfunction. Diastolic dysfunction can induce ventricular repolarization dispersion. Nevertheless, myocardial repolarization dispersion is not yet to be fully evaluated in patients with AAA. We aimed to evaluate ventricular repolarization using QT and Tp-Te interval and corrected (c) Tp-Te/QT ratio in patients with AAA.

METHODS

One hundred-four patients with AAA without coronary artery disease (CAD) served as the aneurysm group and 82 patients having a normal aortic diameter as the control group. All patients underwent transthoracic echocardiography (TTE) for measurements of LV diastolic function and underwent electrocardiography (ECG) to calculate RR, QT, Tp-Te intervals and QT dispersion. Bazett's formula was used to calculate QTc and cTp-Te intervals. cTp-Te/QT ratio was also calculated.

RESULTS

The groups were similar according to basal characteristics. We found left ventricular diastolic properties were impaired and QT dispersion, QTc interval, and both of Tp-Te and cTp-Te intervals were significantly prolonged in the aneurysm group than the control group. There were also significant correlations between TTE and ECG parameters. On multivariate linear regression analysis, indexed ascending aortic dimension (AAoD), LA diameter and E/e' ratio were independent predictors of ventricular repolarization dispersion in AAA patients.

CONCLUSIONS

Our study results showed that patients with AAA may have an increased risk for ventricular arrhythmogenesis because of deteriorated the left ventricular diastolic function.

Assessment of myocardial repolarisation parameters in patients with familial Mediterranean fever

Background:

Familial Mediterranean fever (FMF) is a chronic, recurrent auto-inflammatory disease characterised by self-terminating attacks of fever and sterile polyserositis. The main cause of death in auto-inflammatory diseasesis cardiovascular events. Additionally, auto-inflammatory diseases have potential effects on the myocardial repolarisation parameters, including the T-wave peak-to-end (Tp-Te) interval, cTp-Te interval (corrected Tp-Te) and the cTp-Te/ QT ratio. The aim of this study was to analyse the efficacy of myocardial repolarisation alterations in anticipation of cardiovascular risks in patients with FMF.

Methods:

This study included 66 patients with FMF and 58 healthy control subjects. Tp-Te and cTp-Te intervals and the cTp-Te/QT ratio were measured from the 12-lead electrocardiogram.

Results:

In electrocardiographic parameters, analysis of QT, QT dispersion, corrected QT (QTc) and QTc dispersion were similar between the groups. The Tp-Te and cTp-Te intervals and Tp-Te/QT and cTp-Te/QT ratios were significantly prolonged in FMF patients. Multivariate linear regression analyses indicated that erythrocyte sedimentation rate was an independent predictor of a prolonged cTp-Te interval.

Conclusions:

Our study revealed that when compared with control subjects, Tp-Te and cTp-Te intervals and cTp-Te/QT ratio were increased in FMF patients.

Prognostic value of Tpeak-Tend interval in patients with acute pulmonary embolism

Background

The aim of this study was to examine the Tpeak-Tend (Tpe/corrected Tpe) interval, which is an indicator of transmural myocardial repolarization, measured non-invasively via electrocardiogram in patients with acute pulmonary embolism (PE), and to investigate the relationship with 30-day mortality and morbidity.

Methods

The study included 272 patients diagnosed with acute PE, comprising 154 females and 118 males, with a mean age of 63.1 ± 16.8 years. Tpe/cTpe intervals were calculated from the electrocardiograms with a computer program after using a ruler or vernier caliper manual measuring tool to obtain highly sensitive measurements. The relationship between the electrocardiogram values and 30-days mortality and morbidity were measured.

Results

The study group was divided into three groups according to cTpe intervals: Group 1, < 113 ms; Group 2, 113–133 ms; and Group 3, > 133 ms. White blood cell count and troponin T levels, corrected QT intervals with QRS complex durations, percentage of right ventricle dilatation with right/left-ventricular ratio, 30-day death, and combinations of these values were seen at a higher rate in Group 3 patients compared to the other groups. Kaplan–Meier analysis showed that the cTpe interval measured at > 126 ms could be used as a cut-off value in the prediction of mortality and morbidity. The cTpe cut-off values of 126 ms had sensivity, specificity, negative predictive value, and positive predictive value of 80.56 %, 59.32 %, 95.2 %, and 23.2 %, respectively.

Conclusions

cTpe interval could be a useful method in early risk stratification in patients with acute PE.

Exercise-Induced Repolarization Changes in Patients with Isolated Myocardial Bridging

BACKGROUND

Although myocardial bridging (MB) is defined as an angiographic phenomenon with a benign course, it has also been associated with adverse cardiovascular events. The effects of exercise on myocardial repolarization in patients with MB were tested in this study, with Tp-e and Tp-e/QT repolarization indexes.

MATERIAL AND METHODS

A total of 50 patients in whom isolated MB was diagnosed at coronary angiography (CAG) (Group I) and 48 patients with normal CAG results (Group II) were included in this study. The participants underwent treadmill exercise stress testing according to the Bruce protocol. QT dispersion (QTd) was defined as the minimum QT interval subtracted from the maximum. The Tp-e interval was defined as the difference between the QT and the QT peak time period. QTd and Tp-e intervals were calculated for all patients before and after exercise testing and differences between groups were compared.

RESULTS

At peak exercise, QTd and cQTd showed a significant increase in comparison to baseline values in the group of patients with myocardial bridges. Significant increases were also found with exercise in the Tp-e, cTp-e durations and Tp-e/QT ratio of the MB patient group in comparison to the baseline values. On the other hand, significant differences in QTd, cQTd, Tp-e, cTp-e intervals, and Tp-e/QT ratio during peak exercise in comparison with baseline values were not detected in the control group (p>0.05).

CONCLUSIONS

Significant increases in QTd, cQTd, Tp-e and cTp-e intervals and Tp-e/QT ratio were detected in the MB patients during exercise testing.

Increased Tpeak-Tend interval is highly and independently related to arrhythmic events in Brugada syndrome

BACKGROUND

Risk stratification in Brugada syndrome (BS) remains controversial. The time interval between the peak and the end of the T wave (Tpe interval), a marker of transmural dispersion of repolarization, has been linked to malignant ventricular arrhythmias in various settings but leads to discordant results in BS.

OBJECTIVE

We study the correlation of the Tpe interval with arrhythmic events in a large cohort of patients with BS.

METHODS

A total of 325 consecutive patients with BS (mean age 47±13 years, 259 men-80%) with spontaneous (n=143, 44%) or drug-induced (n=182, 56%) type 1 electrocardiogram were retrospectively included. 235 were asymptomatic (70%), 80 presented with unexplained syncope (22%), and 10 presented with sudden death (SD) or appropriate implantable cardioverter-defibrillator therapy (AT) (8%) at diagnosis or over a mean follow-up of 48 ± 34 months. The Tpe interval was calculated as the difference between the QT interval and the QT peak interval as measured in each of the precordial leads.

RESULTS

The Tpe interval from lead V1 to lead V4, maximum value of the Tpe interval (max Tpe), and Tpe dispersion in all precordial leads were significantly higher in patients with SD/AT or in patients with syncope than in asymptomatic patients (P < .001). A max Tpe of ≥100 ms was present in 47 of 226 asymptomatic patients (21%), in 48 of 73 patients with syncope (66%), and in 22 of 26 patients with SD/AT (85%) (P < .0001). In multivariate analysis, a max Tpe of ≥100 ms was independently related to arrhythmic events (odds ratio 9.61; 95% confidence interval 3.13-29.41; P < .0001).

CONCLUSION

The Tpe interval in the precordial leads is highly related to malignant ventricular arrhythmias in this large cohort of patients with BS. This simple electrocardiographic parameter could be used to refine risk stratification.