Electrocardiographic Parameters Research Articles

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 ± 15.80years) and 281 control subjects (180 females, 101 males; mean age 53.38 ± 15.72years). 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 ± 26.62ms vs 422.72 ± 11.7ms, 104.16 ± 24.34ms vs 77.23 ± 16.25ms and 0.27 ± 0.06ms vs 0.20 ± 0.04ms, 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 ± 24.89ms vs 438.55 ± 26.37ms, 114.05 ± 22.68ms vs 101.53 ± 24.13ms, and 0.29 ± 0.06ms vs 0.27 ± 0.05ms, 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.

Primary Protection of Diosmin Against Doxorubicin Cardiotoxicity via Inhibiting Oxido-Inflammatory Stress and Apoptosis in Rats.

Doxorubicin (DOX) is the cornerstone of chemotherapy. However, it has dose-dependent cardiotoxic events that limit its clinical use. This study was intended to investigate the efficiency of DOX as an anti-cancer against the MCF-7 cell line in the presence of diosmin (DIO) and to appraise the protective impact of DIO against DOX cardiotoxicity in vivo. In vitro study was carried out to establish the conservation of DOX cytotoxicity in the presence of DIO. In vivo study was conducted on 42 adult female Wistar rats that were equally allocated into 6 groups; control, DIO (100 mg/kg), DIO (200 mg/kg), DOX (20 mg/kg, single dose i.p.), DIO (100 mg/kg) + DOX, received DIO orally (100 mg/kg) for 30 days, then administrated with a single dose of DOX and DIO (200 mg/kg) + DOX, received DIO orally (200 mg/kg) for 30 days, then administrated with DOX. In vitro study showed preservation of cytotoxic activity of DOX on MCF-7 in the presence of DIO. In vivo study indicated that DOX altered electrocardiograph (ECG) parameters. Also, it yielded a significant rise in CK-MB, cTnT and LDH serum levels and cardiac contents of MDA, IL-1β; paralleled by a significant drop in cardiac IL-10 and SOD. Moreover, significant upregulation of Bax, TNF-α, and HIF-1α, in concomitant with significant downregulation of Bcl-2 mRNA in cardiac tissue have been recorded in the DOX group. Furthermore, histopathological description of cardiac tissues showed that DOX alters normal cardiac histoarchitecture. On the opposite side, DIO pretreatment could ameliorate ECG parameters, suppress IL-1β and enhanceIL-10, promote activity of SOD and repress MDA. Additionally, downregulation of Bax, TNF-α, HIF-1α and upregulation of Bcl-2 have been demonstrated in DIO-pretreated rats. Furthermore, the histopathological examination of cardiac tissues illustrated that DIO had a favorable impact on the protection of heart histoarchitecture. DIO is suggested for protection against acute cardiotoxicity caused by DOX without affecting antitumor activity.

ПОТЕНЦИАЛ ИСПОЛЬЗОВАНИЯ ДИНАМИКИ ЭЛЕКТРОКАРДИОГРАФИЧЕСКИХ ПОКАЗАТЕЛЕЙ ПРИ ВЫЯВЛЕНИИ КАРДИОТОКСИЧНОСТИ ЧЕРЕЗ 12 МЕСЯЦЕВ ПОСЛЕ ОКОНЧАНИЯ ХИМИОТЕРАПИИ РАКА МОЛОЧНОЙ ЖЕЛЕЗЫ ДОКСОРУБИЦИНОМ

Background. Changes in electrocardiographic parameters of the heart, reflecting the processes of depolarization and repolarization of the myocardium, can be signs of early cardiotoxicity (CT). Aim. To study changes in electrocardiographic parameters of the myocardium in patients with verified breast cancer 12 months after the end of chemotherapy with doxorubicin. Material and methods. The study included 100 patients with a confirmed diagnosis of breast cancer who were treated at the health care institution “Grodno University Clinic” (Grodno, Belarus). A number of electrocardiographic parameters of the myocardium were measured in patients before and 12 months after the end of chemotherapy using electrocardiography and 24-hour Holter monitoring. Results. A statistically significant increase in electrocardiographic parameters of depolarization and repolarization was revealed (P, P-Q, Tpeak-Tend, Q-Tc / QRS, Q-Tc - p&lt;0.007; p&lt;0.001; p=0.042; p=0.009; p&lt;0.001, respectively) before and 12 months after the end of chemotherapy. A change in the time and total number of episodes of sinus tachycardia and supraventricular extrasystoles was also noted (p=0.029, p=0.026 and p=0.002). The Tpeak-Tend indicator changed statistically significantly in the CT+ subgroup (p=0.032) after 12 months. The dynamics of the Q-Tc indicator before and 12 months after the end of chemotherapy was observed in almost all patients. However, in the CT+ subgroup, an increase in Q-Tc was recorded statistically significantly more often compared to the CT- subgroup (p &lt;0.005). Conclusion. During chemotherapy with doxorubicin, an increase in Tpeak-Tend and Q-Tc was observed. An especially significant increase in these indicators was noted in the CT+ subgroup. The number and duration of sinus tachycardia episodes as well as the number of supraventricular extrasystoles also increased. This may correlate with the relationship between chemotherapy with doxorubicin and the dynamics of electrocardiographic parameters.

Using AI to identify left ventricular ejection fraction from the ECG: The SOLOMAX (SOciaL NetwOrk of MedicAl Experiences) project

Aim: The interest in machine learning-based algorithms in the cardiovascular field is rapidly growing, especially for diagnostic and prognostic purposes. Recent evidence has demonstrated that certain electrocardiographic (ECG) parameters are predominantly associated with systolic function, estimated as left ventricular ejection fraction (LVEF) by echocardiography, albeit with still relatively low accuracy. Consequently, this study aims to develop an AI-based model capable of predicting LVEF from ECG data in an Italian population. Methods: Within the SOLOMAX project, we collected paired ECG-Echocardiography exams from 105 patients (64.82±16.02y;62.86%male). Precisely, we excluded patients with atrial fibrillation at the time of the ECG, PMK or electrostimulated rhythm, valve prostheses, previous cardiac surgery, O2 therapy or COPD, previous ablation or invasive electrophysiology procedures, currently hospitalized for Takotsubo or ACS, heart failure exacerbation, inotropic therapy, ACS over the last 3 months. We recorded anthropometric, clinical, biochemical, ECG, and Echocardiography parameters. The collected data was studied using AI-based techniques to create a new model to predict LVEF from ECG. Using an approach based on evolutionary algorithms, genetic programming was used. This approach solves a symbolic regression problem through genetic algorithms and provides a mathematical model of the relationship between ECG parameters and LVEF. The formula obtained was then used to build a simple explainable classifier, which provides a global interpretation of the link between ECG parameters and LVEF. Results: The performance of the proposed approach and the reliability of the results were assessed using the k-fold cross-validation method and by estimating standard metrics derived from the confusion matrix associated with a binary classifier, that is, accuracy, sensitivity, specificity, precision, and F-Measure. The proposed approach consistently demonstrated its ability to distinguish patients with preserved LVEF from those with reduced LVEF. Each metric averaged across all experiments scored approximately 95%. Furthermore, in the expression generated by the AI model, the axes of the P, QRS, and T waves play a prominent role, as they are likely to provide a better interpretation of the three-dimensional cardiac geometry and, consequently, cardiac function. Conclusions: AI applied to ECG data can be used to create cost-effective diagnostic and predictive tools for assessing LVEF. Indeed, the obtained formula highlights the relationship between ECG parameters and LVEF, as well as its complexity, which can aid in detecting heart diseases.

Assessment of Heart Rate Variability in Children with Mitral Valve Prolapse.

Mitral valve prolapse (MVP) is a heart valve anomaly with specific electrocardiographic findings and arrhythmia. A predominant sympathetic tone and diminished vagal activity have been reported especially in symptomatic MVP patients. In the current study, we aim to review heart rate variability (HRV) parameters of MVP children in order to determine if there is an impaired autonomic regulation. The data of children with MVP were retrospectively analyzed. Demographic characteristics, body mass index, symptomatology, MVP type and mitral regurgitation, MVP-related electrocardiographic changes, arrhythmia, and HRV parameters in 24-h Holter monitoring were recorded. HRV parameters of the control group were obtained from children applying for sport participation. Statistical significance limit was accepted as p < 0.05. 154 of the patients (74.8%) were girls, the median age was 13.58 ± 2.99years. While MVP patients had shorter PR intervals, those who had syncope had longer PR intervals. Short PR distance may be a feature of MVP, long PR distance may be a condition associated with syncope with the underlying paroxysmal atrioventricular block. Moreover, the minimum heart rate was significantly lower in the MVP group compared to the control and there were no significant differences in terms of remaining parameters. The number of low LF values was higher in MVP patients than the control. Comparing HRV values of groups by gender, we found that overall HRV parameters were lower in girls with MVP while minimum, maximum, and average heart rate were lower in boys with MVP. Impaired HRV associated with MVP could be age, gender, and symptom related. In addition, low LF may indicate impaired baroreflex sensitivity in MVP patients.

The effect of an anti-malarial herbal remedy, Maytenus senegalensis, on electrocardiograms of healthy Tanzanian volunteers

BackgroundThe emergence of resistance to artemisinin-based combination therapy necessitates the search for new, more potent antiplasmodial compounds, including herbal remedies. The whole extract of Maytenus senegalensis has been scientifically investigated for potential biological activities both in vitro and in vivo, demonstrating strong antimalarial activity. However, there is a lack of data on the electrocardiographic effects of M. senegalensis in humans, which is a crucial aspect in the investigation of malaria treatment. Assessing the electrocardiographic effects of M. senegalensis is essential, as many anti-malarial drugs can inadvertently prolong the QT interval on electrocardiograms. Therefore, the study's objective was to evaluate the electrocardiographic effects of M. senegalensis in healthy adult volunteers.MethodsThis study is a secondary analysis of an open-label single-arm dose escalation. Twelve healthy eligible Tanzanian males, aged 18 to 45, were enrolled in four study dose groups. A single 12-lead electrocardiogram (ECG) was performed at baseline and on days 3, 7, 14, 28, and 56.ResultsNo QTcF adverse events occurred with any drug dose. Only one volunteer who received the highest dose (800 mg) of M. senegalensis experienced a moderate transient change (△QTcF > 30 ms; specifically, the value was 37 ms) from baseline on day 28. There was no difference in maximum QTcF and maximum △QTcF between volunteers in all four study dose groups.ConclusionsA four-day regimen of 800 mg every 8 h of M. senegalensis did not impact the electrocardiographic parameters in healthy volunteers. This study suggests that M. senegalensis could be a valuable addition to malaria treatment, providing a safer alternative and potentially aiding in the battle against artemisinin-resistant malaria. The results of this study support both the traditional use and the modern therapeutic potential of M. senegalensis. They also set the stage for future research involving larger and more diverse populations to explore the safety profile of M. senegalensis in different demographic groups. This is especially important considering the potential use of M. senegalensis as a therapeutic agent and its widespread utilization as traditional medicine.Trial registration ClinicalTrials.gov, NCT04944966. Registered 30 June 2021-Retrospectively registered, https://clinicaltrials.gov/ct2/show/NCT04944966?term=kamaka&draw=2&rank=1

The effect of anabolic androgenic steroids on heart rate recovery index and electrocardiographic parameters in male bodybuilders

BackgroundThe control of the cardiovascular system depends on the autonomic nerve system. Chronic anabolic andorogenic steroids (AAS) use causes sympathovagal imbalance and increases sympathetic nerve activity. ObjectiveThe reduction in heart rate from the peak exercise rate following the end of the exercise stress test is known as the heart rate recovery index (HRRI). Several methods have been utilized to assess myocardial repolarization, such as QT interval (QT), corrected QT interval (QTc), and T-wave peak-to-end interval (Tp-e interval). Based on a growing number of data a higher Tp-e/QT ratio is linked to malignant ventricular arrhythmias, and an increased Tp-e interval may correlate with the transmural dispersion of repolarization. Our hypothesis is that the use of chronic AAS was decrease HRRI during maximal exercise and increased risk of cardiac arrhythmias and sudden cardiac death. MethodsThis study included 44 male bodybuilders, with an average age of 29.7 ± 8.14 years, divided into AAS abuse [AAS users (n = 21) and AAS nonuser (n = 23)]. ResultsThe first (p = 0.001) and second minute (p = 0.001) HRRI of the subjects with AAS users were significantly lower than those of the control group. Additionally, HRRI after the third (p = 0.004) and fifth minutes (p = 0.007) of the recovery period were significantly lower in AAS group compared with the control group. Who used AAS had significantly higher QT, QTc, Tp-e, Tp-e/QT, and Tp-e/QTc values than non-users (all p = 0.001). ConclusionsChronic AAS use has been shown to cause sympathetic dominance, which may be a pro arrhythmic state.

Electrocardiography changes and different stages of heart failure in central Iran: A cross-sectional study from Yazd Health Study.

Electrocardiography (ECG) is a widely accessible, noninvasive, and cost-effective diagnostic instrument used to evaluate patients with suspected heart failure (HF). The aim of this study is to investigate electrocardiographic changes in patients with different stages of HF in a random population of Yazd city. This prospective cross-sectional study included 319 individuals, randomly selected, aged 40 years and more, registered in the Yazd Health Study was conducted from March 2022 to May 2023 at Afshar Hospitals. In accordance with the AHA/ACC guidelines, HF was classified into four stages (A, B, C, and D). The 159 individuals were classified in the stage 0 group, 77 were in Stage A, 65 were in Stage B, and 18 were in Stage C of HF. In the Stage 0, the PR interval (PRi) was 130.5 ± 18.1 ms, while in Stage C, it was 143.3 ± 21.9 ms, with a significant difference (p = 0.047). Similarly, the QRS interval (QRSi) increased with HF staging (p = 0.001). The frequency of diabetes mellitus (DM), hypertension (HTN), hyperlipidemia (HLP), chronic heart disease, alcoholism, and PRi, QRSi, QT interval levels were independent predictors of HF stage in multivariate regression analysis. The prevalence of HF stages, as classified by the AHA/ACC guidelines, was observed, with significant correlations between ECG parameters and HF progression. abnormal rhythms, left bundle branch block, ischemia, hypertrophy, and left atrial enlargement increased with higher HF stages. Major risk factors like DM and HTN exhibited a heightened prevalence in advanced HF stages, accentuating their pivotal role in the progression of HF.

A novel prediction model for myocardial fibrosis in patients suspected of myocarditis

Purpose: This study aimed at establishing a predictive method that consists of clinical, electrocardiographic (ECG), and laboratory parameters for myocardial fibrosis, especially as detected on cardiac magnetic resonance imaging (CMRI), in patients examined with suspicion of myocarditis.&#x0D; Materials and Methods: This study is a retrospective, single-centre study that includes patients admitted to our centre with suspected myocarditis between March 2020 and November 2023. Participants were categorised into two groups (myocardial fibrosis positive and myocardial fibrosis negative), and a detailed comparison of comorbidities, ECG changes, and laboratory parameters was performed. Multivariate analysis was conducted to identify independent predictors of myocardial fibrosis. A nomogram was constructed using the coefficients from the multivariate analysis to estimate the probability of myocardial fibrosis presence based on key predictors. &#x0D; Results: This study included 98 participants with a median age of 30 years, predominantly male (80.6%), with 14.3% having hypertension, 8.2% having diabetes mellitus, and 10.2% being smokers. The myocardial fibrosis-negative group exhibited higher levels of left ventricular ejection fraction and lymphocyte count. Conversely, the myocardial fibrosis-positive group showed higher levels of ECG changes at admission, peak C-reactive protein (CRP), CRP velocity, peak troponin, N-terminal pro-brain natriuretic peptide (NT-proBNP), monocytes, and platelets (PLT). In multivariate analysis, PLT, lymphocyte, monocyte, peak troponin, and ECG changes were identified as independent predictors of myocardial fibrosis. Receiving operating characteristic (ROC) curve analysis showed the model's diagnostic accuracy for predicting myocardial fibrosis (area under the ROC (AUC): 0.959, 95% confidence interval (CI), and p

Electrocardiographic signs of cardiovascular system dysfunction in the context of various courses of COVID-19 in young and middle-aged individuals

BACKGROUD: Intensive monitoring of patients with the coronavirus disease should include functional monitoring of the cardiovascular system. Physiologic methods can detect dysfunction of the cardiovascular system, however, it is not always possible to identify initial or hidden dysfunction. Therefore, clinical data should be complemented with results from instrumental methods, particularly electrocardiography. AIM: To identify preclinical electrocardiography signs of cardiovascular system dysfunction in the context of various courses of coronavirus disease in young and middle-aged individuals. MATERIALS AND METHODS: A retrospective analysis of 337 medical records of young and middle-aged individuals (40.0 ± 13.3 years old) was conducted. The analysis of the medical records included electrocardiograms in 12 leads with the assessment of standard parameters, results of laboratory and instrumental tests. In order to identify the main factors predicting an unfavorable course of the coronavirus disease, a factor analysis was conducted using electrocardiography parameters. Logistic regression analysis was used to develop a statistical model for predicting the likelihood of a severe course and fatal outcome of COVID-19, followed by assessing the diagnostic value of the prognostic model using the ROC curve and determining the area under the curve. RESULTS: The main factors predicting an unfavorable course of the new coronavirus disease in young and middle-aged individuals based on electrocardiography data include the α angle factor, the ventricular repolarization factor and the heart rate factor. In addition, as electrocardiography predictors, the elongation of the P wave and PQ interval, the amplitude of the R wave in lead one, the decrease in the T wave amplitude in the precordial leads, and the amplitude of the R wave in leads two and three can be considered. Based on the identified electrocardiography predictors, a mathematical model for predicting a severe course and fatal outcome of the new coronavirus disease was developed. CONCLUSIONS: Thus, electrocardiography is an indicative method that can be influenced by infectious process which is performed for all individuals upon admission to the hospital, allowing this examination to be considered the most accessible for detecting preclinical signs of an unfavorable course of COVID-19.

Multicenter prospective observational study to clarify the current status and clinical outcome in Japanese patients who have an indication for implantable cardioverter defibrillator (ICD) or wearable cardioverter defibrillator (WCD) (TRANSITION JAPAN‐ICD/WCD study): Rationale and design of a prospective, multicenter, observational, comparative study

AbstractBackgroundDespite the positive impact of implantable cardioverter defibrillators (ICDs) and wearable cardioverter defibrillators (WCDs) on prognosis, their implantation is often withheld especially in Japanese heart failure patients with reduced left ventricular ejection fraction (HFrEF) who have not experienced ventricular tachycardia (VT) or ventricular fibrillation (VF) for uncertain reasons. Recent advancements in heart failure (HF) medications have significantly improved the prognosis for HFrEF. Given this context, a critical reassessment of the treatment and prognosis of ICDs and WCDs is essential, as it has the potential to reshape awareness and treatment strategies for these patients.MethodsWe are initiating a prospective multicenter observational study for HFrEF patients eligible for ICD in primary and secondary prevention, and WCD, regardless of device use, including all consenting patients. Study subjects are to be enrolled from 31 participant hospitals located throughout Japan from April 1, 2023, to December 31, 2024, and each will be followed up for 1 year or more. The planned sample size is 651 cases. The primary endpoint is the rate of cardiac implantable electronic device implementation. Other endpoints include the incidence of VT/VF and sudden death, all‐cause mortality, and HF hospitalization, other events. We will collect clinical background information plus each patient's symptoms, Clinical Frailty Scale score, laboratory test results, echocardiographic and electrocardiographic parameters, and serial changes will also be secondary endpoints.ResultsNot applicable.ConclusionThis study offers invaluable insights into understanding the role of ICD/WCD in Japanese HF patients in the new era of HF medication.

Polistemi Vera ve Esansiyel Trombositemi Tanısı Alan Hastalarda Elektrokardiyografik ve Ekokardiyografik Bulgularının Değerlendirilmesi

Background/Aims: Polycythemia vera (PV) and essential thrombocythemia (ET) are chronic myeloproliferative diseases. Along with the increase in myeloproliferative cell lines, they can cause various clinical outcomes such as arterial and venous thrombosis, pulmonary hypertension, and myocardial infarction. This study was designed to evaluate the cardiac effects of these diseases via electrocardiography and echocardiography. Methods: A total of 50 patients with a diagnosis of PV, 50 patients with a diagnosis of ET, and 50 healthy individuals as a control group were included in this study. Data on patient demographics were recorded in all subjects. All patients and control subjects had electrocardiography (ECG) recordings and routine transthoracic echocardiographic examination. Pulse wave velocity (PWV) was assessed with a Holter blood pressure device. Results: In total, 50 PV patients, 50 ET patients, and 50 control group were included in the study. The demographic characteristics of the PV, ET and control groups were similar. The PR interval was significantly shorter in control subjects than in PV and ET patients (p:0.007, p:0.024). Although the measured values were within normal limits, diastolic posterior wall thickness was significantly lower in the control group compared to PV and ET patients (p:0.019, p:0.009). PWV was significantly higher in ET patients compared to the control group (p:0.012). Conclusion: In this study, evaluating the effects of PV and ET on electrocardiography and transthoracic echocardiography; ECG parameters used to predict ventricular arrhythmias (QT, QTc, Tp-Te, Tp-Te/QT) and Pulmonary Artery Pressure showed no significant change, in opposition to existing literature. Nonetheless, similar to previous publications, PV and ET were found to negatively affect the diastolic function parameters on transthoracic echocardiography. While the aortic stiffness was significantly higher in ET patients compared to the control group, no significant difference was noted between PV patients and control subjects in terms of aortic stiffness.

Relationship between Vitamin D Level and Index of Cardio Electrophysiological Balance in Children.

Vitamin D deficiency has been found to be associated with various cardiovascular disorders, including hypertension, coronary artery disease, heart failure, peripheral vascular diseases, and sudden cardiac death. In the literature, it has been reported that many electrocardiographic parameters have been developed to predict ventricular arrhythmias. In recent studies, it is noteworthy that the index of cardio-electrophysiological balance (iCEB) and correct cardio-electrophysiological balance (iCEBc), which are electrocardiographic parameters, can be used as new, easy, cheap and non-invasive parameters to predict ventricular arrhythmias. This study aimed to investigate the relationship between vitamin D deficiency and iCEB and iCEBc values in children. A total of 186 patients were included in this study. Group 1 included 114 patients with vitamin D levels below 20 ng/ml; 50 patients with vitamin D levels of 21-29 ng/ml were included in Group 2; Group 3 consisted of 36 patients with a vitamin D level above 30 ng/ml. iCEB and iCEBc values were calculated by taking 12-lead ECG from all individuals and comparing them between groups. A total of 186 children, 114 subjects in Group 1, 36 subjects in Group 2, and 36 subjects in Group 3, were included in the study. Demographic characteristics and height-weight values of the groups were similar. Significant differences were found between the groups in terms of QT, QTc, QT/QRS, and QTc/QRS levels (p: 0.003, 0.028, 0.001, and 0.001, respectively). In the correlation analysis, a negative correlation was found between QTc/QRS and vitamin D level (r=-0.320, p=<0.001) and between QT/QRS and vitamin D level (r=-0.268, p=<0.001). Moreover, vitamin D level (β=0.389, p<0.001) was determined as an independent predictor of QTc/QRS in multivariate logistic regression analysis. iCEB and iCEBc parameters increase significantly in children with low vitamin D levels. These parameters are also evaluated during the follow-up of children with vitamin D deficiency in terms of the risk of ventricular arrhythmia. iCEBc can be used as an easy, inexpensive, non-invasive, and reproducible parameter.

A Simple Score for Predicting Paroxysmal Atrial Fibrillation in Patients with Embolic Stroke of Undetermined Source in a Tunisian Cohort Study.

The annualized recurrent stroke rate in patients with Embolic Stroke of Undetermined Source (ESUS) under antiplatelet therapy is around 4.5%. Only a fraction of these patients will develop atrial fibrillation (FA), to which a stroke can be attributed retrospectively. The challenge is to identify patients at risk of occult AF during follow-up. This work aims to determine clinical factors and electrocardiographic and ultrasound parameters that can predict occult AF in patients with ESUS and build a simple predictive score applicable worldwide. This is a single-center, registry-based retrospective study conducted at the stroke unit of Sahloul University Hospital, Sousse, Tunisia, between January 2016 and December 2020. Consecutive patients meeting ESUS criteria were monitored for a minimum of one year, with a standardized follow-up consisting of outpatient visits, including ECG every three months and a new 24-hour Holter monitoring in case of palpitations. We performed multivariate stepwise regression to identify predictors of new paroxysmal AF among initial clinical, electrocardiographic (ECG and 24-hour Holter monitoring) and echocardiographic parameters. The coefficient of each independent covariate of the fitted multivariable model was used to generate an integerbased point-scoring system. Three hundred patients met the criteria for ESUS. Among them, 42 (14%) patients showed at least one episode of paroxysmal AF during a median follow-up of two years. In univariate analysis, age, gender, coronary artery disease, history of ischemic stroke, higher NIHSS at admission and lower NIHSS at discharge, abnormal P-wave axis, prolonged P-wave duration, premature atrial contractions (PAC) frequency of more than 500/24 hours, and left atrial (LA) mean area of more than 20 cm2 were associated with the risk of occurrence of paroxysmal AF. We proposed an AF predictive score based on (1.771 x NIHSS score at admission) + (10.015 x P-wave dispersion; coded 1 if yes and 0 if no) + (9.841x PAC class; coded 1 if ≥500 and 0 if no) + (9.828x LA class surface; coded 1 if ≥20 and 0 if no) + (0.548xNIHSS score at discharge) + 0.004. A score of ≥33 had a sensitivity of 76% and a specificity of 93%. In this cohort of patients with ESUS, NIHSS at both admission and discharge, Pwave dispersion, PAC≥500/24h on a 24-hour Holter monitoring, and LA surface area≥20 cm2 provide a simple AF predictive score with very reasonable sensitivity and specificity and is applicable almost worldwide. An external validation of this score is ongoing.

Predictor of A4 amplitude using preprocedural electrocardiography in patients with leadless pacemakers

BackgroundBased on historical studies of leadless pacemakers (LPs), high atrioventricular synchrony (AVS) with mechanical sensing-based VDD pacing is largely influenced by A4 amplitude. A limited study investigated the predictors of A4 amplitude using clinical and echocardiographic parameters. ObjectiveThe purpose of this study was to investigate the predictors of A4 amplitude preoperatively to select patients who could benefit the most from AVS among patients with VDD LPs (Micra-AV, Medtronic). MethodsData from patients who received Micra-AV implantations from November 2021 to August 2023 at Tottori University Hospital were analyzed. Twelve-lead electrocardiography and transthoracic echocardiography were performed before the Micra-AV implantations. To assess the electrical indices associated with the A4 signal, electrocardiographic morphologic P-wave parameters were analyzed, including P-wave duration, P-wave amplitude, maximum deflection index (MDI), and P-wave dispersion. ResultsA total of 50 patients who underwent Micra-AV implantations (median age 84 years; 64% male) were included and divided into 2 groups based on the median value of A4 amplitude, the high-A4 group (A4 amplitude >2.5 m/s2; n = 26), and low-A4 group (A4 amplitude ≤2.5 m/s2; n = 24). There was a significant difference between the high-A4 and low-A4 groups with regard to left ventricular ejection fraction (P = .01), P-wave dispersion (P = .01), and MDI (P <.001). Multivariate logistic analysis revealed that lower MDI was an independent predictor of high A4-amplitude (odds ratio 0.78; 95% confidence interval 0.67–0.92; P = 0.003). ConclusionPreoperative electrocardiographic evaluations of P-wave morphology may be useful for predicting A4 amplitude. MDI was the only independent A4 amplitude predictor that seemed promising for selecting Micra-AV patients.

A comparison of electrocardiographic parameters in e-cigarette users, conventional cigarette smokers, and non-smokers

BackgroundSmoking is a major preventable risk factor for cardiovascular morbidity and mortality. Tobacco smoking induces atherosclerosis, ischemic heart diseases, and arrhythmias. The impact of electronic cigarettes on cardiovascular health is still controversial. This study aimed to evaluate the electrocardiographic parameters in chronic electronic cigarette users compared to chronic conventional cigarette smokers and a non-smoker control group of matched age and gender.ResultsThe study involved 105 volunteers with no history of chronic or cardiovascular diseases or cardioactive drug use. Participants were assigned into three study groups, chronic e-cigarette users, conventional cigarette smokers, and non-smokers, each consisting of 35 participants. Demographic data, smoking history, vital signs, and 12-lead electrocardiogram (ECG) were evaluated. Demographic data were insignificantly different among all study groups. The mean heart rate was significantly higher in chronic electronic cigarette users and conventional cigarette smokers compared to non-smokers (p < 0.001).QRS complex duration was significantly shorter in e-cigarette users and conventional smokers compared to non-smokers (p < 0.001). Prolonged QT and QTc intervals duration were recorded in e-cigarette users and conventional smokers compared to non-smokers (p < 0.001). All the ventricular repolarization indices (T wave—peak to T-end (Tpe) interval, TPe/QT ratio, and TPe/QTc ratio were significantly prolonged in chronic e-cigarette users, and conventional smokers compared to non-smokers (p < 0.001). Mean systolic, diastolic blood pressure, P wave amplitude and duration, and PR interval were insignificantly different between all groups (P > 0.05).ConclusionsChronic e-cigarette use is associated with higher heart rates, shorter QRS complex, prolonged QT, QTc duration, and prolonged ventricular repolarization indices compared to non-smokers of matched age and gender. Conclusively, e-cigarette use is associated with negative cardiovascular effects like conventional cigarette smoking.

Evaluation of Tp-e interval, Tp-e/QT, and Tp-e/QTc ratio in primary hyperparathyroidism before and after parathyroidectomy

Aims: This study aimed to evaluate Tp-e interval, Tp-e/QT ratio, and Tp-e/QTc ratios, which are new ventricular repolarization (VR) parameters in primary hyperparathyroidism (PHPT) patients, and also investigate the potential effect of parathyroidectomy (PTx) on these parameters. Methods: In total, 27 patients with PHPT who underwent PTx and 25 control subjects were selected for our study. Tp-e interval, Tp-e/QT ratio, and Tp-e/QTc ratios of patients planned for PTx were compared to healthy matched controls. Electrocardiographic parameters measured 6 months after the surgery were also compared with preoperative values for each patient. Results: Tp-e interval, Tp-e/QT ratio, and Tp-e/QTc ratio were significantly higher in PHPT patients compared to the control group (p&amp;lt;0.001, for all).It was observed that the parameters mentioned after surgery decreased significantly, and there was no statistical difference when compared to the control group.The correlation analysis revealed a significant and positive correlation between corrected calcium (CCa) and PTH levels with Tp-e interval, Tp-e/QT ratio, and Tp-e/QTc ratio (for Ca; r=0.515, p=0.006; r=0.398, p=0.040; r=0.797, p&amp;lt;0.001 respectively vs. for PTH; r=538, p=0.04; r=0.422, p=0.028; r=0.812, p&amp;lt;0.001 respectively). Conclusions: This study showed that Tp-e interval, Tp-e/QT, and Tp-e/QTc ratios were prolonged in PHPT.These values, which are accepted as an indicator of sudden cardiac death after PTx, decreased significantly. In addition, both high PTH and high calcium(Ca) levels appear to have the potential to cause arrhythmogenic effects separately.

Amyloid Burden Correlates with Electrocardiographic Findings in Patients with Cardiac Amyloidosis-Insights from Histology and Cardiac Magnetic Resonance Imaging.

Cardiac amyloidosis (CA) is associated with several distinct electrocardiographic (ECG) changes. However, the impact of amyloid depositions on ECG parameters is not well investigated. We therefore aimed to assess the correlation of amyloid burden with ECG and test the prognostic power of ECG findings on outcomes in patients with CA. Consecutive CA patients underwent ECG assessment and cardiac magnetic resonance imaging (CMR), including the quantification of extracellular volume (ECV) with T1 mapping. Moreover, seven patients underwent additional amyloid quantification using immunohistochemistry staining of endomyocardial biopsies. A total of 105 CA patients (wild-type transthyretin: 74.3%, variant transthyretin: 8.6%, light chain: 17.1%) were analyzed for this study. We detected correlations of total QRS voltage with histologically quantified amyloid burden (r = -0.780, p = 0.039) and ECV (r = -0.266, p = 0.006). In patients above the ECV median (43.9%), PR intervals were significantly longer (p = 0.016) and left anterior fascicular blocks were more prevalent (p = 0.025). In our survival analysis, neither Kaplan-Meier curves (p = 0.996) nor Cox regression analysis detected associations of QRS voltage with adverse patient outcomes (hazard ratio: 0.995, p = 0.265). The present study demonstrated that an increased amyloid burden is associated with lower voltages in CA patients. However, baseline ECG findings, including QRS voltage, were not associated with adverse outcomes.

Electrocardiogram in different types of dizziness

We have studied the influence of neurological loadings on heart rate (HR) in patients with dizziness and correlations between types of dizziness and changes in the electrocardiography (ECG) parameters. Two hundred and twenty-one patients aged 44.82 ± 14.15 years were examined. ECG and HR have been recorded before and after neurological loadings: calculation, Takahashi, tracking, lowering the bed and diadochokinesis. All the tests resulted in HR changes. The data obtained have been discussed from the point of view of somatomorphic disorders, cardiac neurosis (F45.3 according to ICD-10) and the possibility of their detection in patients with cardiac complaints in whom ECG studies did not reveal any abnormalities. Correlations between certain types of dizziness and ECG interval indicators are discussed.

Effects of insulin resistance on cardiovascular risk factors in obese and non-obese patients

Objectives: It is known that insulin resistance increases cardiovardiovascular risk. But it could not obviously be understood whether insulin resistance itself or the metabolic syndrome parameters, like obesity, that already exist in most of them, are responsible for this increased risk. Our aim is to determine cardiovascular risks in obese and non-obese insulin-resistant patients. Methods: One hundred thirty-nine patients were included in the study. They were divided into 4 groups: Group 1 (having obesity and insulin resistance), Group 2 (having only insulin resistance but not obesity), Group 3 (having obesity but not insulin resistance), and Group 4 (having neither obesity nor insulin resistance). Patients having any systemic disease were excluded. Insulin resistance is calculated via Homeostatic Model Assessment of Insulin Resistance (HOMA-IR) formula. Electrocardiographic, echocardiographic and lipid parameters of these patients were compared. Results: High-density lipoprotein (HDL) levels of Group-4 were higher than Group 1 and Group 2. There was no statistical difference in HDL cholesterol levels between Group 3 and the others. Triglyceride and very low-density lipoprotein levels were higher in Group 1. There was no difference in P wave dispersion between the groups. In echocardigraphy, epicardial fat tissue thickness of Group 1 was significantly higher. Prevalance of diastolic dysfunction was higher in Group 1 compared to Group 4. Conclusions: Insulin resistance itself is a risk factor for low HDL levels independent of obesity. When obesity is added to insulin resistance, other cardiovascular risk factors appear, like high triglyceride levels, increase in epicardial fat tissue thickness and presence of diastolic dysfunction. Early detection of insulin resistance may alert us to the risks of cardiovascular diseases.