Index of cardiac electrophysiological balance and transmural dispersion of the repolarization index relationships with pericardial fat volume and coronary calcification

Effect of the index of cardiac electrophysiological balance on major adverse cardiovascular events in patients with diabetes complicated with coronary heart disease

Purpose

To investigate the prognostic value of the index of cardio-electrophysiological balance (ICEB) and its association with major adverse cardiac events (MACE) and cardiovascular death in diabetic patients complicated with coronary heart disease.

Methods

A total of 920 diabetic patients were enrolled in this longitudinal study. Participants were categorized into three groups based on their ICEB levels: normal ICEB, low ICEB, and high ICEB. The primary outcome was the occurrence of MACE, and secondary outcomes included cardiovascular death, coronary heart disease (CHD), heart failure (HF), and sudden cardiac arrest (SCA). Patients were followed for a median period of 3.26 years, and the associations between ICEB levels and various outcomes were evaluated.

Results

Over the follow-up period, 46 (5.0%) MACE were observed in the normal ICEB group, 57 (6.2%) in the low ICEB group, and 62 (6.8%) in the high ICEB group. Elevated ICEB levels were found to be associated with a higher risk of MACE and cardiovascular death. A significant relationship between ICEB levels and the risk of MACE was observed for both genders. The risk of MACE increased with each unit increment in the ICEB index. However, the two-stage linear regression model did not outperform the single-line linear regression models in determining the threshold effect.

Conclusion

This study demonstrates the potential utility of ICEB, derived from a standard non-invasive ECG, as a prognostic tool for predicting MACE and cardiovascular death in diabetic patients complicated with CVD. The associations between ICEB levels and the risk of MACE highlight the importance of understanding cardiac electrophysiological imbalances and their implications in CVD.

Evaluation of index of cardiac-electrophysiological balance in patients with subarachnoid hemorrhage

Background

Various electrocardiographic (ECG) changes occur after subarachnoid hemorrhage (SAH). Prolonged QT and corrected QT (QTc) intervals are notable changes. QT, QTc, T peak-to-end T(p-e) intervals, and Tp-e/QTc ratio are used as ventricular arrhythmia indices. In recent publications, the cardiac electrophysiological balance index (ICEB), which provides more information than other ECG parameters (QT, QTc, etc.), is recommended in predicting the risk of ventricular arrhythmia. This study aims to assess ICEB in aneurysmal SAH patients.

Methods

The study included 50 patients diagnosed with aneurysmal SAH and 50 patients diagnosed with hypertension without end-organ damage as the control group. All patients’ Fisher scores and Glasgow Coma Scale (GCS) scores were recorded. Both groups were given 12-lead ECGs. QT, QTc, Tp-e intervals, QRS duration, ICEB (QT/QRS), ICEBc (QTc/QRS), and T(p-e)/QTc values were calculated and analyzed between groups.

Results

Compared to the control group; QT (426,64 ± 14,62 vs. 348,84 ± 12,24 ms, p < 0,001), QTc (456,24 ± 28,84 vs. 392,48 ± 14,36 ms, p < 0,001), Tp-e (84,32 ± 3,46 vs. 70,12 ± 3,12, p < 0,001), Tp-e/QTc (0,185 ± 0,08 vs. 0,178 ± 0,02, p < 0,001), ICEB (4,53 ± 0,78 vs. 3,74 ± 0,28, p < 0,001) and ICEBc (4,86 ± 0,86 vs. 4,21 ± 0,24, p < 0,001) were significantly higher in patients with aneurysmal SAH. QT, QTc and Tp-e interval, Tp-e/QTc ratio, ICEB (QT/QRS) and ICEBc (QTc/QRS) were positively correlated with the Fisher score and were negatively correlated with the GCS. According to linear regression analyses, the ICEBc (QTc/QRS) found to be independently associated with the Fisher score.

Conclusion

The values of the ICEB and ICEBc were significantly increased in patients with aneurysmal SAH. The severity of SAH was positively correlated with the ICEB and ICEBc. The ICEBc (QTc/QRS) independently associated with the Fisher score. This may that SAH suggest may predispose to malignant ventricular arrhythmias.

Evaluation of Tp-e interval, Tp-e/QT ratio and index of cardiac-electrophysiological balance in patients with tinnitus

Background

Tinnitus is a common auditory symptom. Dysfunction in the autonomic nervous system (ANS) is an essential part of the etiopathogenesis of tinnitus. ANS regulates heart rate and heart rhythm and can lead to ventricular repolarization changes, which can cause malignant ventricular arrhythmias. T wave peak-to-end T(p-e) interval and T(p-e)/QT ratio are known ventricular arrhythmia indexes, and the index of cardiac-electrophysiological balance (iCEB) is a novel index that can be used to predict the risk of malignant ventricular arrhythmia. The goal of the study was to investigate these ventricular arrhythmia indexes in patients with tinnitus.

Methods

The study population consisted of 240 patients with tinnitus and 240 healthy subjects. A standard 12-channel surface electrocardiogram was applied to both groups. T(p-e) interval, QT interval and QRS duration were determined. Corrected QT (QTc) was determined via Bazett’s formula. To predict ventricular arrhythmia, iCEB (QT/QRS), T(p-e)/QT, corrected iCEB (QTc/QRS) and T(p-e)/QTc values were determined and compared between groups.

Results

Compared to the control group, QT (376.46 ± 36.54 vs 346.52 ± 24.51 ms), QTc (426.68 ± 24.68 vs 390.42 ± 24.04 ms), T(p-e) (75.86 ± 14.68 vs 62.42 ± 8.64 ms), T(p-e)/QT (0.201 ± 0.06 vs 0.180 ± 0.01) and T(p-e)/QTc (0.177 ± 0.06 vs 0.159 ± 0.02) were significantly higher in patients with tinnitus (p < 0.001 for all). QT/QRS (3.92 ± 0.68 vs 3.56 ± 0.32) and QTc/QRS (4.44 ± 1.03 vs 4.01 ± 0.64) were also significantly higher in patients with tinnitus (p = 0.018 and p = 0.008, respectively). In addition, significant positive correlations were found between T(p-e), T(p-e)/QTc ratio and disease duration (r = 0.792, p < 0.001; r = 0.500, p < 0.001, respectively).

Conclusion

As a result, patients with tinnitus may have an increased risk of malignant ventricular arrhythmia.

ECG markers of malignant arrhythmias and in-hospital outcome of COVID-19 pneumonia

Background

ECG abnormalities associated with COVID-19 pneumonia and adverse outcome are undefined and poorly described in prior studies.

Objectives

To assess the predictive role of baseline ECG markers of increased risk of malignant arrhythmias and cardiac death for adverse in-hospital outcomes.

Patients and methods

A retrospective study included 93 patients of newly diagnosed COVID-19 with features consistent with pneumonia who were admitted to the hospital from August 20 to September 20, 2020. The main outcomes were defined as receiving mechanical ventilation, in-hospital cardiac arrest, length of ICU stay, and degree of lung damage according to computed tomography (CT) score.

Results

Increased QTc (QT corrected) interval, Tp-e (T from peak to end) interval, and transmural dispersion of repolarization (TDR) were independent predictors of prolonged ICU stay (P < .0001) after adjustment for baseline clinical characteristics. Increasing age (P < .0001) followed by increased QTc interval (P = .02) and history of chronic lung disease (P = .04) were independent predictors of extensive lung damage. The independent predictors for in-hospital cardiac arrest were increased QTc (P = .02) followed by increasing age (P = .04) and increased Tp-e interval (P = .04).

Conclusion

Repolarization abnormalities on baseline ECG may be useful prognostic markers in patients with COVID-19 pneumonia.

Electrocardiographic markers of increased risk of sudden cardiac death in patients with COVID-19 pneumonia

Background

Little is known about the role of ECG markers of increased risk of sudden cardiac death during the acute period of coronavirus disease 2019 ( COVID‐19) pneumonia.

Objectives

To evaluate ECG markers of sudden cardiac death on admission, including the index of cardiac electrophysiological balance (iCEB) (QTc/QRS) and transmural dispersion of repolarization (TDR) (T from peak to end (Tp‐e) interval and Tp‐e/QTc), in patients with COVID‐19 pneumonia.

Patients and methods

This cross‐sectional study included 63 patients with newly diagnosed COVID‐19 pneumonia who presented to the outpatient clinic or admitted to the respiratory care unit between August 20 and September 15, 2020. Forty‐six persons matched for sex and age were selected from data collected before COVID‐19 pandemic.

Results

QRS and QTc showed a significant prolongation in patients with COVID‐19 pneumonia compared to the controls (87 vs. 78, p < .00, and 429 versus. 400, p < .00, respectively). After categorization of patients with COVID‐19 pneumonia into 3 groups according to the severity of pneumonia as mild‐moderate, severe, and critical groups, a decreased values of QRS were observed in the critical COVID‐19 pneumonia group compared to severe and mild‐moderate COVID‐19 pneumonia groups (p = .04) while increased values of QTc and iCEB(QTc/QRS) were noted in critical COVID‐19 pneumonia group compared to other 2 groups(p < .00).

Conclusions

Patients with COVID‐19 pneumonia showed significant changes in repolarization and conduction parameters compared to controls. Patients with mild to severe COVID‐19 pneumonia may be at low risk for torsades de pointes development.

Evaluation of index of cardiac-electrophysiological balance before and after hemodialysis in patients with end-stage renal disease

BACKGROUND

Ventricular arrhythmias and sudden cardiac deaths are the most common cause of mortality in patients with end-stage renal disease (ESRD). Index of cardiac-electrophysiological balance (iCEB) (QT/QRS) may predict malignant ventricular arrhythmias. In this study, we investigated whether iCEB value is increased in ESRD patients and whether it changes before and after hemodialysis.

METHODS

The study included 52 ESRD patients and 53 control subjects matched for age and comorbidities. Biochemical, electrocardiographic and echocardiographic values of all participants were recorded. QRS, QT, Tp-e were measured manually. QTC was calculated using Bazett's formula. Then, Tp-e/QT, Tp-e/QTc, QT/QRS, and QTc/QRS ratios were calculated. The changes in ECG parameters of the ESRD patients before and after HD were compared using paired t-test.

RESULTS

Mean age and male sex ratio was comparable in both groups (p = 0.448 and p = 0.777, respectively). Comorbidity incidences, and biochemical parameters except eGFR (p < 0.001), albumin (p < 0.001), HDL cholesterol (p = 0.03) and platelet counts (p < 0.001) were comparable in both groups. Compared to the control group, QT, QTc, Tp-e, Tp-e/QT, Tp-e/QTc, QT/QRS, and QTc/QRS ratios were higher in the ESRD group (p < 0.05 for each). While QT and QTc intervals did not change after HD in ESRD patients, Tp-e, Tp-e/QT, Tp-e/QTc, QT/QRS, and QTc/QRS parameters increased significantly.

CONCLUSION

In addition to ventricular repolarization dispersion indices in ESRD patients, iCEB elevation and increasing values after HD session indicate the increased risk of TdP-mediated ventricular arrhythmia after HD. Larger studies are needed to confirm our results.