Search Results (125)

Background: Left bundle branch block (LBBB) following trans-catheter aortic valve implantation (TAVI) has been excluded from same-day discharge. Early identification of patients with stable LBBB can help facilitate same-day discharge. We aim to assess the role of 6-hour ECG to determine development of LBBB in patients undergoing TAVI. Methods: This is a prospective single-centre study of patients who have LBBB following elective TAVI procedures. All patients underwent ECGs pre-TAVI, as well as immediately, 6 h, and 24 h post-TAVI. Changes in ECG were compared at 6 and 24 h with the one immediately post TAVI. Results: The study included 115 patients with uncomplicated procedures. The mean age was 81 ± 7 years, with 54% male. A self-expanding valve was used in 67% of patients. Following TAVI, prolongations of PR interval and QRS duration were dynamic and reduced at 6 h. The change in PR interval at 6 and 24 h was comparable [−11 (−20 to 3) vs. −2 (−24 to 16) ms, p = 0.18]. Similarly, there was no statistical difference in the change of QRS duration at 6 and 24 h compared to the ECG immediately post-TAVI [−10 (−40 to −2) vs. −7 (−34 to 0) ms, p = 0.055]. Changes in ECG were also comparable in patients undergoing balloon-expandable and self-expanding valves. Conclusions: The current study supports that 6-hour ECG has the potential to reduce the need for prolonged continuous monitoring post-TAVI. ECG at 6 h can help optimise patient flow and facilitate early discharge. Future studies with larger sample sizes are required to confirm our findings. Full article

Background: The cardiovascular effects of SARS-CoV-2, including autonomic dysregulation, are becoming increasingly recognized, even following mild infections. However, long-term electrocardiographic (ECG) changes remain poorly characterized. Methods: We conducted a prospective study of 151 unvaccinated healthcare workers with RT-PCR-confirmed mild to moderate SARS-CoV-2 infection. Standard 12-lead ECGs were recorded before infection (T0) and at 6–12 months (T1) and >12 months (T2) after infection. Key parameters included heart rate (HR), PR interval, QRS duration, and corrected QT interval (QTc). Results: Heart rate (HR) increased transiently at T1 (p < 0.05) and normalized by T2. Mild but persistent PR interval shortening was observed at both follow-ups (p < 0.01). There were no significant changes in QRS or QTc intervals. No arrhythmias or conduction blocks occurred. ECG alterations were not associated with sex or age, except for greater PR shortening in males. Conclusions: Mild SARS-CoV-2 infection can result in transient sinus tachycardia and subtle PR shortening, which is likely to be a post-viral autonomic effect. Long-term ECG surveillance appears unnecessary in asymptomatic cases. Full article

Aim: The frontal QRS-T (fQRS-T) angle serves as an electrocardiography indicator that visually represents the disparity between the frontal QRS axis and the T axis. The heterogeneity between cardiac depolarization and repolarization rises with an increase in the fQRS-T angle. Prior research has demonstrated a relationship between the fQRS-T angle and the extent of atherosclerosis, along with the risk of cardiovascular mortality. The non-alcoholic fatty liver disease fibrosis score (NFS) is a non-invasive scoring tool used to quantify the degree of liver fibrosis in individuals with non-alcoholic fatty liver disease (NAFLD). Non-alcoholic fatty liver disease increases the risk of atherosclerotic cardiovascular disease, which can be predicted using the NFS. The objective of this study is to examine the potential correlation between the fQRS-T angle and NFS in patients with stable angina pectoris. Materials and Methods: This cross-sectional study included 177 (48 women) non-alcoholic patients who underwent coronary angiography due to stable angina pectoris. Individual NFS values were calculated using clinical and laboratory data. Patients were categorized into two groups based on a NFS threshold value of 0.67. Following a minimum fasting period of 12 h, biochemical laboratory parameters were acquired using a peripheral venous sample, and electrocardiographic data were recorded. Results: The univariate logistic regression analysis revealed significant associations between hypertension (p = 0.018), coronary artery disease (p = 0.014), neutrophil (p = 0.024), hemoglobin (p = 0.038), and low-density lipoprotein (LDL, p = 0.007) with the NFS. The electrocardiographic variables related to the score included the QRS duration (p = 0.015), Pmax (p = 0.026), QTC interval (p = 0.02), and fQRS-T angle (p < 0.001). In the multivariate logistic regression analysis, NFS was independently associated with LDL (OR: 0.984, 95% CI: 0.970–0.998, p = 0.024) and fQRS-T angle (OR: 3.472, 95% CI: 1.886–6.395, p < 0.001). Conclusions: The FQRS-T angle may exhibit a distinct correlation with NAFLD. Extensive investigations should validate this link, since the fibrosis score can serve as an effective tool for monitoring patients prior to the onset of clinical symptoms associated with liver fibrosis. Full article

Background: The early repolarization pattern (ERP) on electrocardiography (ECG) has been associated with an increased risk of ventricular arrhythmias in susceptible individuals. This study aimed to evaluate the impact of exercise on echocardiographic parameters to explore the potential influence of ERP on hemodynamic response. Methods: Twenty-five healthy, young males with ERP (ERP+ group) and 25 age-matched healthy males without ERP (ERP− group) were enrolled. Comprehensive transthoracic echocardiography was performed at rest and during the early recovery phase following a treadmill exercise test. Baseline values and exercise-induced changes in both conventional and strain-derived echocardiographic parameters were analyzed and compared between groups. Results: Anthropometric measures and resting vital signs were similar in both groups. At baseline, the ERP+ group had a shorter QRS duration. Both groups demonstrated excellent cardiovascular fitness, with comparable chronotropic and pressor responses to exercise. Resting and early recovery-phase echocardiographic parameters were largely similar between ERP+ and ERP− individuals, with no overt structural or functional abnormalities observed in either group. However, ERP+ individuals showed significantly greater reductions in left ventricular end-diastolic volume and stroke volume following exercise, suggesting a distinct volumetric response to physical stress. Conclusions: ERP in healthy young males is not associated with structural cardiac abnormalities or overt myocardial dysfunction. The observed exercise-induced volumetric changes may indicate subtle differences in hemodynamic adaptation, warranting further investigation. Full article

Background and Objectives: The role of biventricular pacing (BVP) is less well-established in patients with heart failure with reduced ejection fraction (HFrEF) without left bundle branch block (LBBB). Conduction system pacing (CSP) has gained significant traction and may provide a safe and more physiological alternative to BVP in these patients. A few small studies studying this question have reported conflicting results. This meta-analysis aims to compare procedural and clinical outcomes between CSP and BVP in this group. Materials and Methods: An online literature search was systematically conducted to retrieve studies comparing CSP and BVP in HFrEF patients with non-LBBB. Four studies with 461 patients were included. Results: Implant-derived paced QRS duration was significantly shorter (mean difference [MD] −19.7 ms, 95% confidence interval [CI] −36.2 to −3.3, p = 0.0355) with CSP. Echocardiographic response with significantly greater improvement in left ventricular ejection fraction (MD 5.6%, 95% CI 3.1 to 8.0, p = 0.0106) was also observed with CSP. There were no statistically significant differences in clinical outcomes such as all-cause mortality (relative risk [RR] 0.53, 95% CI 0.18 to 1.60, p = 0.133) and heart failure hospitalization (RR 0.54, 95% CI 0.19 to 1.56, p = 0.129). Conclusions: This meta-analysis suggests that CSP may have better electrical synchrony and echocardiographic response compared to BVP in HFrEF patients with non-LBBB. Further randomized studies with longer follow-up may be required to elucidate potential benefits in clinical outcomes. Full article

Background/Objectives: Although cardiac resynchronization therapy (CRT) plays an established role in the management of heart failure, a significant proportion of patients do not respond despite appropriate candidate selection. The optimization of CRT pacing is one strategy to enhance response. Fusion pacing algorithms aim to synchronize intrinsic right ventricular (RV) conduction with paced left ventricular (LV) activation, resulting in a more physiological ventricular depolarization pattern. This approach may improve electrical synchrony and enhance left ventricular contraction compared to conventional simultaneous biventricular pacing. The aim of this study was to compare the acute, beat-to-beat effects of standard biventricular pacing versus fusion pacing on myocardial function, using both conventional and speckle-tracking echocardiography in heart failure patients with left bundle branch block (LBBB). Methods: In total, 27 heart failure patients (21 men and 6 women) with reduced ejection fraction (EF < 35%), left bundle branch block (QRS > 150 ms), and newly implanted CRT-D systems (Abbott) underwent echocardiographic assessment immediately after device implantation. Echocardiographic parameters—including left atrial strain, left ventricular strain, TAPSE, mitral and tricuspid valve function, and cardiac output—were measured at 5 min intervals under three different pacing conditions: pacing off, simultaneous biventricular pacing, and fusion pacing using Abbott’s SyncAV^® algorithm. Results: In our study, CRT led to a significant shortening of the QRS duration from 169 ± 19 ms at baseline to 131 ± 17 ms with standard biventricular pacing, and further to 118 ± 16 ms with fusion pacing (p < 0.05). Despite the electrical improvement, no significant changes were observed in global longitudinal strain (GLS: −9.15 vs. −9.39 vs. −9.13; p = NS), left ventricular stroke volume (67.5 mL vs. 68.4 mL vs. 68.5 mL; p = NS), or left atrial parameters including strain, area, and ejection fraction. However, fusion pacing was associated with more homogeneous segmental strain patterns, improved aortic valve closure time, and enhanced right ventricular function as reflected by tissue Doppler-derived S’. Conclusions: Immediate QRS narrowing observed in CRT patients—particularly with fusion pacing optimization—is associated with a more homogeneous pattern of left ventricular contractility and improvements in selected measures of mechanical synchrony. However, these acute electrical changes do not translate into immediate improvements in stroke volume, global LV strain, or left atrial function. Longer-term follow-up is needed to determine whether the electrical benefits of CRT, especially with fusion pacing, lead to meaningful hemodynamic improvements. Full article

Background/Objectives:Pacing treatment of bradyarrhythmias is both to reduce symptoms and to prevent syncope and sudden cardiac death. The aim of our study was to analyze left bundle branch area pacing (LBBAP) in the prevention of new-onset AF and the improvement of echocardiographic parameters in patients with mildly reduced left ventricular ejection fraction (LVEF) compared to patients with bradyarrhythmias but preserved LVEF who underwent mid-septal right ventricular pacing. Methods: This research was structured as a retrospective observational cohort study that included 186 patients with LBBAP and 186 patients with RVP, enrolled for 3 years until March 2024 with a follow-up time of 1 year. The primary endpoint of our study was new-onset atrial fibrillation after pacemaker implantation. The secondary endpoint was the improvement of echocardiographic parameters. Results: We observed in the LBBAP group a mean QRS complex duration of 108.7 ± 8.83 ms (after pacemaker implantation), compared to a much longer duration in the RVP group (143.8 ± 9.851 ms, p = <0.0001). At 1 year of follow-up, 22 (11.82%) patients in the RVP group were diagnosed with new-onset atrial fibrillation, compared to 6 (3.22%) patients out of 186 included in the LBBAP group (p = 0.0017). Regarding LVEF, at follow-up, RVP patients had a decrease in LVEF compared to those in the LBBAP group who had an improved LVEF (54.54 ± 3.77%, p < 0.0001). Conclusions: LBBAP both prevents the onset of atrial fibrillation and improves echocardiographic parameters, especially left ventricular ejection fraction, thus contributing to significantly reducing the risk of developing/worsening advanced heart failure through pacing-induced cardiomyopathy. Full article

Background: Conduction system pacing (CSP), encompassing His bundle pacing (HBP) and left bundle branch area pacing (LBBAP), has emerged as an alternative to conventional pacing methods such as right ventricular pacing (RVP) and biventricular pacing (BVP). This meta-analysis aimed to compare the effects of CSP versus conventional pacing on left ventricular function and selected clinical and electrophysiological outcomes. Methods: Prospective and retrospective studies (randomized, observational, registry-based) reporting pre-post data or direct comparisons between CSP (HBP, LBBAP) and conventional methods (BVP, RVP) for at least one of LVEF, LVESV, LVEDV, QRS duration, NYHA class, NT-proBNP, R-wave, or pacing threshold were included. PubMed and Web of Science databases were searched up to 31 March 2025. Quality assessment (QualSyst), publication bias (Egger’s test, trim-and-fill), subgroup analyses, and meta-regression (follow-up duration) were performed. The review was registered in the INPLASY database (INPLASY202540050). Results: 28 studies (8777 patients, 47 comparisons) were included. CSP significantly improved LVEF (SMD = 1.16; 95%CI: 0.94–1.38), shortened QRS duration (SMD = 0.75; 95%CI: 0.24–1.26), and reduced NYHA class (SMD = 1.94; 95%CI: 1.59–2.29), NT-proBNP levels (SMD = 1.27; 95%CI:0.85–1.69), LVEDV (SMD = 0.90; 95%CI: 0.42–1.38), and LVESV (SMD = 1.31; 95%CI: 0.81–1.81). In head-to-head comparisons, LBBAP and HBP showed similar efficacy, both superior to conventional pacing. Improvement in LVEF significantly correlated with longer follow-up (p = 0.004). Publication bias was non-significant (Egger p = 0.15), despite high heterogeneity (I² > 90%). Conclusions: CSP demonstrated superior clinical and echocardiographic outcomes compared to conventional pacing. Limitations include the predominance of non-randomized studies, high heterogeneity, and variability in follow-up duration, supporting the need for high-quality randomized trials. Full article

Background and Objectives: Major depressive disorder (MDD) is a prevalent psychiatric illness increasingly recognized as a systemic condition with implications for cardiovascular diseases. Growing evidence indicates that individuals with MDD have an elevated risk of cardiovascular mortality, underscoring the need for reliable, non-invasive biomarkers to assess cardiac risk. While underlying mechanisms remain unclear, electrocardiogram (ECG)-based markers offer a promising, non-invasive means of evaluation. Among these, the electrical risk score (ERS), a composite derived from specific ECG parameters, has emerged as a predictor of adverse cardiac outcomes. This study aimed to investigate the association between ERS and MDD, and whether ERS correlates with depression severity and illness duration. Materials and Methods: In this retrospective cross-sectional study, 12-lead ECGs were evaluated to calculate the ERS based on six ECG parameters: heart rate, corrected QT interval, Tp-e interval, frontal QRS-T angle, QRS transition zone, and presence of left ventricular hypertrophy according to Sokolow–Lyon criteria. The Hamilton Depression Rating Scale (HAM-D) was utilized. Results: The study included 102 patients with MDD and 62 healthy controls. No significant differences were observed in baseline or laboratory parameters between the groups. However, heart rate, Tp-e interval, frontal QRS-T angle, and ERS were significantly higher in the depression group. ROC analysis identified ERS as the strongest predictor of depression. ERS was significantly higher in patients with severe depression compared to those with mild symptoms and showed a positive correlation with both disease duration and HAM-D score. Conclusions: Here, we show that the ECG-derived ERS is significantly elevated in patients with MDD and is associated with increased cardiac risk. ERS outperformed conventional ECG parameters in identifying individuals with depression and demonstrated positive associations with both illness duration and symptom severity. These findings suggest that ERS may serve as a practical, non-invasive biomarker for assessing cardiovascular vulnerability in this population. Full article

Background and Objectives: Post-term pregnancies are associated with increased risks of perinatal complications. This study aimed to evaluate potential cardiac electrophysiological changes in pregnant women by comparing the QRS duration, interval of corrected QT (QTc), and frontal QRS-T angle [f(QRS-T)] between term and post-term pregnancies. Materials and Methods: In this observational prospective study, 120 pregnant women were enrolled—60 term (37–41 weeks) and 60 post-term (≥42 weeks). All participants underwent standard 12-lead electrocardiography (ECG) and caesarean section with spinal anaesthesia. The QTc interval, QRS duration, and frontal QRS-T angle were measured. Demographic parameters such as age, gestational week, height, and weight were recorded. The SPSS software was used to analyse the data with p < 0.05 as the threshold for significance. Results: Post-operative QTc interval (417.3 ± 20.5 vs. 410.2 ± 14.5, p = 0.032) and f(QRS-T) (28 [16–55] vs. 22 [14–34], p = 0.042) were significantly higher in the post-term group than in the term group. When the change in the f(QRS-T) angle was analysed, there was a significant widening of this angle in the post-term group (from 21 [11–37] to 28 [16–55], p = 0.002). The increased f(QRS-T) angle reflects greater heterogeneity in ventricular depolarisation and repolarisation, which may indicate sub-clinical myocardial stress or altered autonomic regulation in the post-term period. Although no overt arrhythmias were observed, subtle changes in P-wave morphology and QT dispersion were more prevalent in the post-term group. Conclusions: Prolonged QRS duration and an increased f(QRS-T) angle in post-term pregnancies can reflect the underlying changes in cardiac electrophysiology related to prolonged gestation. These ECG parameters may serve as non-invasive indicators of sub-clinical cardiac stress, which could be relevant for anaesthetic risk assessment and perinatal management. Full article

Conduction system pacing started with His bundle pacing (HBP) and then rapidly switched gears into left bundle branch pacing (LBBP). We describe our center’s experience with LBBP using either lumenless leads (LLLs) or stylet-driven leads (SDLs). Patients who were admitted to two tertiary centers between 1 April 2021 and 30 June 2024 and met the guidelines for pacing were recruited and prospectively followed up. A total of 124 patients underwent permanent pacemaker (PPM) implantation using the LBBP technique with a mean follow-up of 19.7 ± 13.3 months. In total, 90 patients were implanted with LLLs and 34 with SDLs. There was no significant difference in the procedural time and final paced QRS duration, but fluoroscopy time was significantly longer in the SDLs (26.2 ± 17.7 min vs. 17.5 ± 13.0 min, respectively, p = 0.026). The on-table impedance values were also significantly higher in the LLLs, and this persisted throughout the follow-up. There were no differences in the rates of complications. The success of conduction system pacing implantation with SDLs and LLLs is comparable with reasonable safety and reliable outcomes. Good pre-implant patient selection will contribute to improved outcomes. Full article

Background/Objectives: Electrocardiogram data are widely used to diagnose cardiovascular diseases, a leading cause of death globally. Traditional interpretation methods are manual, time-consuming, and prone to error. Machine learning offers a promising alternative for automating the classification of electrocardiogram abnormalities. This study explores the use of machine learning models to classify electrocardiogram abnormalities using a dataset that combines clinical features (e.g., age, weight, smoking status) with key electrocardiogram measurements, without relying on time-series data. Methods: The dataset included demographic and electrocardiogram-related biometric data. Preprocessing steps addressed class imbalance, outliers, feature scaling, and the encoding of categorical variables. Five machine learning models—Gaussian Naive Bayes, support vector machines, random forest trees, extremely randomized trees, gradient boosted trees, and an ensemble of top-performing classifiers—were trained and optimized using stratified k-fold cross-validation. Model performance was evaluated on a reserved testing set using metrics such as accuracy, precision, recall, and F1-score. Results: The extremely randomized trees model achieved the best performance, with a testing accuracy of 66.79%, recall of 66.79%, and F1-score of 62.93%. Ventricular rate, QRS duration, and QTC (Bezet) were identified as the most important features. Challenges in classifying borderline cases were noted due to class imbalance and overlapping features. Conclusions: This study demonstrates the potential of machine learning models, particularly extremely randomized trees, in classifying electrocardiogram abnormalities using demographic and biometric data. While promising, the absence of time-series data limits diagnostic accuracy. Future work incorporating time-series signals and advanced deep learning techniques could further improve performance and clinical relevance. Full article

Background: This study investigates the application of machine learning models to classify electrocardiogram signals, addressing challenges such as class imbalances and inter-class overlap. In this study, “normal” and “abnormal” refer to electrocardiogram findings that either align with or deviate from a standard electrocardiogram, warranting further evaluation. “Borderline” indicates an electrocardiogram that requires additional assessment to distinguish benign variations from pathology. Methods: A hierarchical framework reformulated the multi-class problem into two binary classification tasks—distinguishing “Abnormal” from “Non-Abnormal” and “Normal” from “Non-Normal”—to enhance performance and interpretability. Convolutional neural networks, deep neural networks, and tree-based models, including Gradient Boosting Classifier and Random Forest, were trained and evaluated using standard metrics (accuracy, precision, recall, and F1 score) and learning curve convergence analysis. Results: Results showed that convolutional neural networks achieved the best balance between generalization and performance, effectively adapting to unseen data and variations without overfitting. They exhibit strong convergence and robust feature importance rankings, with ventricular rate, QRS duration, and P-R interval identified as key predictors. Tree-based models, despite their high performance metrics, demonstrated poor convergence, raising concerns about their reliability on unseen data. Deep neural networks achieved high sensitivity but suffered from overfitting, limiting their generalizability. Conclusions: The hierarchical binary classification approach demonstrated clinical relevance, enabling nuanced diagnostic insights. Furthermore, the study emphasizes the critical role of learning curve analysis in evaluating model reliability, beyond performance metrics alone. Future work should focus on optimizing model convergence and exploring hybrid approaches to improve clinical applicability in electrocardiogram signal classification. Full article

Background/Objectives: Secundum-type atrial septal defect (ASD) is one of the most common congenital heart defects, with an incidence of 5.64 per 10,000 live births worldwide. In our study, long-term follow-up results of children who underwent percutaneous ASD closure and patients who underwent surgical treatment were evaluated using right ventricular strain echocardiography and electrocardiography. Methods: 30 patients who underwent transcatheter ASD closure and 30 patients provided with surgical ASD closure were prospectively compared with 50 healthy children with similar demographic characteristics. ECG and transthoracic echocardiography were performed for all patients. The evaluated echocardiography variables are Tricuspid annular plane systolic excursion (TAPSE), 2D right ventricle (RV) and right atrium (RA) dimensions, right ventricular segmental longitudinal strain, and global longitudinal strain. ECG evaluation was performed especially in terms of QRS duration and its correlation with strain echo measurements. Results: The surgical treatment group has statistically significant ASD size compared to patients who underwent transcatheter closure (20 ± 3.6 and 14.87 ± 3.7 mm, p < 0.001). Patients who had surgical treatment have increased RA and RV diameters, and a statistically significant decrease was observed in right ventricular free-wall longitudinal strain and right ventricular four-chamber longitudinal strain compared to patients in transcatheter and the control group (p < 0.001). QRS durations were similarly normal in electrocardiography in the transcatheter and the control groups, and the QRS duration was observed as statistically significantly increased in the patients in the surgical treatment group (p < 0.001). Conclusions: Strain values of the patients who underwent surgical closure were lower, and the QRS values on the ECG were longer, compared to the transcatheter group, which is an indicator that a large ASD diameter has a negative effect on long-term right ventricular function. With this in mind, we argue that early surgical closure is an appropriate treatment option for children whose ASD is large for their age and who are not suitable candidates for transcatheter treatment. Full article

Objective: This study evaluates the short-term cardiovascular effects of guanfacine treatment in children and adolescents with attention deficit/hyperactivity disorder (ADHD). The treatment’s impact on novel electrocardiographic parameters was also investigated. Methods: In a retrospective study conducted between January 2023 and June 2024, 37 patients aged 6–18 years with ADHD underwent baseline and follow-up cardiac evaluations including electrocardiography (ECG) and blood pressure measurements. Novel ECG markers (QRS-T angle, QT dispersion, QTc dispersion, Tp-e interval, Tp-e dispersion, Tp-e/QT ratio, and Tp-e/QTc ratio) were analyzed alongside standard parameters such as heart rate, QT, and corrected QT (QTc) intervals. Guanfacine was initiated at 1 mg and titrated weekly until an optimal clinical response was achieved. Results: Guanfacine treatment led to a significant reduction in heart rate (−12.3 bpm; p < 0.001) and P wave axis (−12.3°; p = 0.038) and an increase in QT interval (+16.8 ms; p = 0.014). However, no significant changes were observed in blood pressure, QTc duration, or the novel ECG parameters. Importantly, the absence of any changes in these advanced markers supports the cardiovascular safety of guanfacine. Two patients experienced side effects (bradycardia and hypotension), leading to treatment discontinuation. ANCOVA analysis indicated that the duration between ECG evaluations significantly influenced the QT interval changes, emphasizing the importance of timing when monitoring cardiovascular effects. Conclusions: Guanfacine demonstrated minor, statistically significant effects on the selected cardiac parameters without clinically meaningful changes to or adverse impacts on the novel ECG markers investigated. As extended-release guanfacine has only been available in Türkiye for the management of ADHD for approximately two years, studies evaluating its clinical efficacy and side effects are critical for clinicians working in this field. Full article