Search Results (191)

Atrial fibrillation (AF) is the most common tachyarrhythmia worldwide. Accompanying the increasing age of the general population, as well as an increase in underlying cardiovascular disease in the United States, is an explosive rise in the incidence and prevalence of this condition. We reviewed observational cohort studies, systematic reviews, meta-analyses, and randomized controlled trials (RCTs) to determine both underlying risk factors and treatment of AF, with particular focus on comorbid conditions influencing treatment success. Numerous studies have demonstrated a reciprocal relationship between maladaptive cardiac remodeling and AF, with the suggestion that aggressive management of both AF itself and resultant cardiovascular disease can lead to reversal of both conditions. Ultimately, many modifiable risk factors for AF exist, with treatment delays associated with a shift towards these conditions becoming unmodifiable. While a large area of focus for AF research has been on determining the optimal pharmacological strategy (i.e., rate versus rhythm control), results have been mixed, with emerging guidelines now pointing towards a flexible treatment strategy that allows for consideration of patient comorbid conditions, medication ease and affordability, and patient preference. Treatment of AF also includes prevention of thromboembolic events. In recent years, novel strategies for surgical or physical occlusion of the left atrial appendage (LAA) with devices such as the Watchman have arisen. Multiple large RCTs have demonstrated the safety and efficacy of these devices, but consideration must be given towards the patient’s bleeding risk, as short-term courses of blood thinners are still considered the standard of care. Finally, emerging therapies for AF include novel drug combinations, neuromodulation devices, and potentially glucagon-like peptide receptor-1 (GLP-1) agonist medications for reduction in overall metabolic disease. Full article

Short QT syndrome (SQTS) is a rare, inherited cardiac channelopathy characterized by an abnormally shortened QT interval, accelerated ventricular repolarization, and an increased risk of atrial and ventricular tachyarrhythmias, including sudden cardiac death (SCD). We report the case of a 14-year-old girl diagnosed with SQTS presenting with persistent atrial fibrillation and a complex independent neurological background. The patient, with no significant family history of cardiac disease or SCD, was incidentally found to have atrial fibrillation and a markedly shortened QT interval during a routine medical evaluation. Although she remained entirely asymptomatic from a cardiovascular perspective, her medical history was notable for maternal Toxoplasma gondii infection during pregnancy, extreme prematurity, and delayed psychomotor development. Electrocardiographic (ECG) findings consistently demonstrated a short QT interval, and genetic testing revealed a likely pathogenic variant in the KCNJ2 gene, consistent with type 3 short QT syndrome (SQTS3). Despite the initiation of antiarrhythmic therapy, atrial fibrillation persisted and the QT interval remained significantly shortened throughout the 24-month follow-up. This case highlights the diagnostic and therapeutic challenges of managing short QT syndrome in pediatric patients, particularly in those who are asymptomatic yet exhibit sustained atrial arrhythmias. It also highlights the coexistence of cardiac channelopathy and neurological comorbidities, emphasizing the importance of a multidisciplinary approach for these distinct clinical entities. Full article

Background and Clinical Significance: The crista terminalis (CT) is a physiological fibromuscular ridge in the right atrium. While benign, rare cases of CT hypertrophy present a diagnostic challenge, as it can mimic a pathological right atrial mass on cardiac imaging. The CT also presents arrhythmogenic potential and is known to be associated with right atrial tachyarrhythmias. Case Presentation: We present the case of a 58-year-old female that presented with rapid, irregular palpitations, accompanied by hypertension. Holter electrocardiography (ECG) confirmed self-limiting episodes of atrial tachycardia (max heart rate 170 bpm). Initial transthoracic echocardiography (TTE) identified an echogenic, non-mobile mass on the posterolateral right atrial wall. Transesophageal echocardiography (TEE) confirmed a 12 × 9 mm homogenous structure with a broad base of implantation and no intrinsic mobility, initially raising the suspicion of an atrial lipoma. Subsequent cardiac computed tomography angiography (CCTA) provided high-resolution tissue characterization, identifying the mass as a hypertrophied CT due to its precise anatomical orientation and its lack of contrast enhancement, also ruling out neoplastic and thrombotic aetiologies. Conclusions: CT hypertrophy is a key differential diagnosis for right atrial masses, particularly in females in their sixth decade. A multimodal imaging approach, transitioning from TTE to TEE and finally CCTA or Cardiac Magnetic Resonance Imaging (CMR), is advantageous in preventing unnecessary invasive interventions or anticoagulation. Full article

Background/Objectives: Palpitations are among the most common reasons for cardiology referrals. Despite widespread use of ambulatory cardiac monitoring, contemporary data from the Middle East are scarce. Extended Holter monitoring provides detailed evaluation of arrhythmia burden, autonomic regulation, and symptom–rhythm correlation in routine clinical practice. Methods: We conducted a prospective observational study of consecutive patients presenting with palpitations who underwent 24–96 h ambulatory Holter monitoring at a cardiology outpatient clinic in Saudi Arabia in 2025. Demographic and clinical characteristics, comorbidities, medication use, echocardiographic parameters, heart rate variability (HRV), ventricular and supraventricular ectopy, tachyarrhythmias, and symptom diary activations were systematically evaluated. Results: Among 251 patients (mean age 41.9 ± 16.4 years; 35.5% male), Holter monitoring showed excellent recording quality (mean analyzable time 98.7 ± 9.5%). Premature ventricular contractions (PVCs) were detected in 53.4% of patients, but burden was low (median 0.0%, IQR 0–0.1%), with only 4.4% exceeding 10%. Atrial premature contractions (APCs) were common (92.0%), though usually low-burden (median burden 0.0%, IQR 0–0.1%); atrial fibrillation and supraventricular tachycardia were rare (0.8% each). Symptom diary activation occurred in 116 patients (46.2%), with 996 events; most (87.9%) correlated with sinus tachycardia, while only 8.6% correlated with PVCs and 2.6% with APCs. In the remaining 53.8% of patients, no symptom–rhythm correlation was documented during monitoring. Heart rate variability showed expected age-related changes. Conclusions: In this predominantly young cohort, Holter monitoring revealed frequent low-burden atrial and ventricular ectopy, whereas clinically significant tachyarrhythmias were uncommon. Holter monitoring up to 96 h provided a diagnostic yield in approximately 50% of patients and should be considered a first-line screening tool. Patients without diagnostic findings may require prolonged monitoring using external or implantable devices. Full article

The global spread of COVID-19 led to the rapid authorization of remdesivir as the first antiviral therapy. However, accumulating clinical evidence has linked its use to cardiac adverse effects. Understanding the mechanisms underlying remdesivir-induced cardiotoxicity is critical for optimizing its clinical use and ensuring patient safety. This study investigates the electrophysiological and molecular features underlying remdesivir-induced cardiac toxicity in male and female guinea pigs, aiming to elucidate the sex-dependent differences in cardiac dysfunction and the role of mitochondria in mediating these effects. A cardiac injury model was established via intraperitoneal administration of remdesivir. In vivo telemetry and ex vivo electrocardiography were used for continuous monitoring of cardiac electrical activity, while optical mapping enabled the assessment of action potential parameters and conduction properties. The histopathological alterations and mitochondrial ultrastructure were examined by hematoxylin–eosin staining and transmission electron microscopy. ELISA and Western blot analyses were performed to explore the inflammatory signaling, apoptosis, and mitochondrial dynamics. Remdesivir induced distinct sex-specific patterns of cardiac toxicity. Compared with female guinea pigs, male guinea pigs had significantly more severe myocardial injury, which was characterized by extensive inflammatory cell infiltration, marked mitochondrial disruption, and a higher incidence of sustained ventricular tachyarrhythmia. Overall, remdesivir was associated with sex-dependent cardiac toxicity, accompanied by mitochondrial impairment and inflammatory activation. Male guinea pigs were more susceptible to electrophysiological instability and mitochondrial dysfunction. These findings highlight the importance of carefully evaluating remdesivir’s cardiac effects and support the need for individualized, sex-specific considerations in its clinical administration. Full article

Background/Objectives: Transcatheter ablation assisted by three-dimensional (3D) electroanatomical mapping (EAM) is the elective treatment for atrioventricular nodal reentrant tachycardia (AVNRT) in children and adolescents. In this population of patients, the most frequently employed EAM strategies are the low-voltage bridge (LVB) strategy and sinus rhythm propagation mapping (SRPM). However, the exact pathophysiology and anatomy of the AVNRT reentrant circuits are still poorly understood. The aim of this study was to investigate the relationship between SRPM and LVB and to shed light on nodal physiology in children and adolescents affected by AVNRT. Methods: We retrospectively collected data on pediatric patients who underwent cryoablation for AVNRT assisted by high-density 3D EAM by using the LVB strategy; maps were reviewed by two independent electrophysiologists and the SRPM was described. SRPM was defined as typical when only one collision area was identified and atypical whenever either no or ≥ two collision areas were localized. Results: Twenty-eight consecutive patients (11.3 ± 3.3 years) were enrolled. All procedures were acutely successful. Overall, atypical SRPM was present in 10 patients (35.7%), and it did not correlate with the presence of multiple SPs or electrophysiological data. Moreover, we observed an imperfect concordance between SRPM and LVB (only in 10/18 patients). When SRPM and LVB were assessed in different locations, the LVB identified the effective cryoablation site in more cases than SRPM (4/8 vs. 1/8). Lastly, in cases of double collision, one collision area co-localized with the LVB and the effective cryoablation spot, whereas the other was located superiorly, closer to the His bundle. Conclusions: Atypical sinus rhythm propagation in the Koch’s triangle is a frequent finding in pediatric AVNRT patients. In this series, LVB showed closer concordance with the successful cryolesion site than retrospectively reconstructed SRPM. Full article

Background and Clinical Significance: Patients with a left ventricular assist device (LVAD) are at risk of ventricular arrhythmias, which are generally hemodynamically tolerated if they occur. In such cases, patients may experience painful implantable cardioverter-defibrillator (ICD) shocks. Case Presentation: A 71-year-old patient with a history of dilated cardiomyopathy caused by a phospholamban (PLN) gain-of-function mutation, with a primary prevention ICD and an LVAD, presented with multiple ICD shocks which she experienced as painful and traumatic. She was found to have ongoing ventricular fibrillation with apparent hemodynamic stability. Conversion to sinus rhythm was achieved through intravenous administration of antiarrhythmic drugs followed by external defibrillation using stacked shocks. Due to the traumatic nature of the shocks, the shock function of the ICD was turned off. Nearly two months later, the patient presented for a second time and was again found to have ventricular fibrillation which had been present for at least six weeks. Conversion to sinus rhythm was unsuccessful and the patient was discharged to her home with an advanced care plan and her LVAD was deactivated. The patient died two months later. Conclusions: Patients with an LVAD can remain hemodynamically stable for prolonged periods of time during ventricular arrhythmias. ICD shocks are therefore mostly experienced as painful and even traumatic. Therefore, the routine use of ICD shock therapy in patients with an LVAD should be reconsidered. Adjustment of ICD programming to higher rates and longer detection may be warranted. Further investigation is warranted regarding a switch to devices with an alarm function rather than therapies for tachyarrhythmias. Full article

Background/Objectives: Portable and wearable ECG technologies are increasingly used in adult cardiac monitoring. However, evidence supporting their feasibility and diagnostic performance in pediatric populations remains limited. This systematic review evaluates the diagnostic accuracy, usability, artifact susceptibility, and user acceptance of mobile ECG technologies in pediatric cardiology. Methods: A systematic literature search was performed in the Embase, PubMed, Scopus, and Web of Science databases. The review was conducted in accordance with the PRISMA 2020 guidelines and was registered in the PROSPERO database. Results: A total of 30 publications were included in the final analysis. Portable ECG devices demonstrated good feasibility diagnostic utility in children. Handheld systems provided high-quality tracings with strong agreement with standard 12-lead ECGs and higher adherence, as well as user satisfaction compared with conventional event recorders. However, automated rhythm classification frequently misidentified pediatric arrhythmias. Smartwatch-based ECG recordings showed high diagnostic accuracy when manually interpreted, but automated algorithms were unreliable, particularly for tachyarrhythmias and conduction abnormalities. Alternative electrode placement strategies improved smartwatch performance, and patient acceptance was consistently high. ECG patch monitoring, particularly with extended-wear devices, achieved the highest diagnostic yield, detecting arrhythmias often missed by short-duration Holter monitoring while maintaining comparable signal quality. Conclusions: Mobile ECG technologies represent a promising adjunct for pediatric rhythm surveillance, offering diagnostic performance comparable to standard modalities when interpreted by clinicians and improved usability and patient acceptance. Persistent limitations include the poor reliability of adult-oriented automated algorithms and the underrepresentation of younger children and the predominantly off-label use of these devices in pediatric populations, underscoring the need for pediatric-specific algorithm development and age-adapted device design. Full article

Severe cases of heart failure (HF), both new onsets of HF and acute exacerbations of chronic HF, are frequently observed during infections. A potentially lethal complication of HF with very low left ventricular ejection fraction is thrombus formation within the heart chambers. A 67-year-old male was admitted to our hospital with shortness of breath after a COVID-19 infection. He was diagnosed with severe acute heart failure and a massive thrombus in the left ventricle. While the thrombus subsided quickly without any observable embolic events, the patient had a lengthy hospitalization stay complicated by tachyarrhythmias and secondary infections. Eventually, his heart failure improved, and he continued to recover post-hospital discharge. We present a case of severe heart failure and intraventricular thrombosis following COVID-19 infection. The patient required potent anti-inflammatory medication in addition to conventional heart failure medication to recover from his HF. Full article

Objective and Background: With the increasing use of catheter ablation for tachyarrhythmias, continuous evaluation of in-hospital complications is essential. This study aimed at analyzing complications associated with catheter ablation for atrial fibrillation (AF), atrial flutter (AFL), and ventricular tachycardia (VT) using nationwide administrative data. Methods: We conducted a retrospective multicentric data analysis from large German ablation centers between 2018 and 2023. Patients were identified using ICD and OPS codes for AF, AFL, and VT regarding predefined in-hospital complications: mortality, stroke, pericardial tamponade, pulmonary embolism, and vascular complications requiring intervention. Results: Among 19,258 ablation procedures from 11 centers, AF was most common (n = 12,241), followed by AFL (n = 5582) and VT (n = 1435). Major complications occurred in 2.2% (n = 433) of cases. VT ablations had the highest complication rate (9.8%), followed by AF (1.6%) and AFL (1.7%). Pericardial tamponade occurred in 0.9% patients, most commonly in VT ablations (4.0%). Vascular complications requiring intervention were reported in 1.1%, while stroke (0.3%) and pulmonary embolism (0.05%) were rare. In-hospital mortality was highest in VT patients (2.4%), compared to AF (0.08%) and AFL (0.13%). Higher AFL mortality as compared to AF was associated with older age and more comorbidities. Upon exploratory analysis, no statistical association between hospital volume and complication rates could be seen. Conclusions: In this multicenter analysis, catheter ablation was associated with a low overall complication rate. VT ablations carried the highest risk, highlighting the impact of structural heart disease and comorbidities. Full article

Exercise stress testing remains one of the most widely used and cost-effective diagnostic tools in clinical cardiology. Beyond the traditional evaluation of induced ischemia, it provides valuable information on functional capacity, blood pressure response and arrhythmic behavior during exercise. In particular, the test plays a crucial role in assessing and interpreting exercise-induced arrhythmias, including tachyarrhythmias, such as premature ventricular beats (PVBs) and bradyarrhythmias, as well as corroborating the suspicion of some ion channel diseases. The usefulness of exercise testing is also highlighted in patients with devices, where it can help evaluate their function and exercise adaptation, as well as in specific conduction disorders, such as Wolff–Parkinson–White syndrome. This practical guide summarizes the key aspects of performing and interpreting the exercise stress test, focusing on hemodynamic and arrhythmic findings and their clinical implications, and includes several illustrative clinical cases. Full article

Background: Radiofrequency catheter ablation for atrial fibrillation (AF) restores sinus rhythm, but late recurrence is common. Left atrial (LA) size is a known predictor of AF recurrence, but the prognostic value of early post-ablation LA remodeling remains underexplored. Objective: We aimed to evaluate whether pre-ablation and early post-ablation LA volume index (LAVI) predict late atrial tachyarrhythmia recurrence after AF ablation. Methods: This is a retrospective single-center study of adults undergoing their first radiofrequency ablation for AF between January 2013 and December 2021. LA volume was measured by transthoracic echocardiography and indexed to body surface area to derive LAVI within one week before ablation and at 6 and 12 months after the procedure. The 6-month echocardiographic assessment was prespecified as the primary early post-ablation time point because it occurs beyond the 3-month blanking period and captures early structural remodeling during routine follow-up. Early recurrence was defined as atrial tachyarrhythmia occurring within 3 months after ablation, and late recurrence (LR) as any atrial tachyarrhythmic event thereafter. Multivariable Cox proportional hazards models were used to identify independent predictors of LR. Results: Among 408 patients with at least one year of follow-up, 157 (38.5%) experienced LR. Age and sex were similar between recurrence and non-recurrence groups (60.7 ± 9.8 vs. 59.9 ± 0.8 years; 56.1% vs. 64.1% male). Recurrence was associated with a higher prevalence of atrial flutter and persistent AF, higher pre-ablation and post-ablation LAVI, and lower post-ablation left ventricular ejection fraction. In multivariable analysis, atrial flutter, persistent AF, and LAVI, measured both before and after ablation, were independent predictors of LR. In receiver operating characteristic analysis, pre-ablation LAVI demonstrated modest discrimination for LR (AUC = 0.622; 95% CI 0.563–0.681; p < 0.001), with an optimal cut-off of 41.6 mL/m², while post-ablation LAVI showed similar performance (AUC = 0.597; 95% CI 0.532–0.662; p = 0.003), with a cut-off of 38.6 mL/m². Overall, discrimination was modest (AUC < 0.65), limiting LAVI as a standalone predictor. Conclusions: Elevated LAVI measured before and early after AF ablation independently predicts LR. Limited post-ablation LA reverse remodeling, reflected by persistently increased LAVI, is associated with unfavorable long-term rhythm outcomes. Serial assessment of LAVI may enhance post-ablation risk stratification. Full article

Obstructive Sleep Apnea (OSA) is a highly prevalent yet frequently underdiagnosed disorder strongly associated with cardiovascular morbidity and mortality. It is characterized by recurrent episodes of intermittent hypoxia, intrathoracic pressure swings, and sleep fragmentation that trigger sympathetic hyperactivation, oxidative stress, systemic inflammation, and progressive structural cardiac remodeling. These mechanisms translate into a wide range of electrocardiographic (ECG) abnormalities, including both nocturnal brady- and tachyarrhythmias, as well as daytime conduction and repolarization changes. This narrative review synthesizes current knowledge on ECG manifestations of OSA, encompassing atrial and ventricular ECG characteristics and the burden of supraventricular and ventricular arrhythmias. Emerging evidence suggests that several daytime ECG markers may represent accessible, low-cost indicators of subclinical cardiac remodeling and autonomic imbalance, with potential clinical implications. In addition, there is a rapidly evolving landscape of artificial intelligence applications and wearable-based ECG monitoring for OSA detection and risk stratification. Standardization of ECG-derived markers, validation across diverse populations, and integration into clinical workflows represent key priorities for future research. Recognizing ECG alterations associated with OSA may support earlier diagnosis, improved arrhythmic risk stratification, and more effective multidisciplinary management. Full article

Background: In the population of patients with ischemic cardiomyopathy (IC) and reduced left ventricular ejection fraction, the benefits of prophylactic implantable cardioverter-defibrillator (ICD) therapy are not uniform. Identifying predictors of ventricular arrhythmias to estimate the risk of appropriate therapy is crucial. Methods: Patients with IC and an ICD for primary prevention implanted between 2006 and 2019 were retrospectively analyzed for appropriate therapy (ATh). The primary objective was to assess predictors of ATh development. The secondary objective was to assess the impact of ATh on survival. Results: Overall, 260 patients (age 67.3 ± 9.4 years, 15.4% female) were analyzed with a follow-up of 4.47 ± 3.02 years. ATh occurred in 79 patients (30.4% of the study group). Independent risk factors for ATh were as follows: non-sustained ventricular tachyarrhythmias (nsVTs) detected before ICD implantation, extensive area of ischemic left ventricular damage on echocardiographic assessment, left ventricular end-diastolic dimension (LVEDd) ≥ 68 mm, history of coronary artery bypass grafting (CABG), and presence of chronic total occlusion (CTO). A multiparameter logit model was created to estimate the probability of ATh. Patients with a score ≥ 0.6 had more than a six-fold higher risk of developing ATh compared with patients with a score < 0.6. Patients after ATh had significantly lower survival compared to patients without intervention (HR 1.69, p = 0.008). Conclusions: Patients with the independent risk factors listed above are at higher risk for ATh. A multiparameter logit model based on these risk factors is effective in estimating the risk of ATh. The occurrence of ATh was associated with a significantly higher risk of all-cause mortality. Full article

Background/Objectives: Ankylosing spondylitis (AS) has been associated with various comorbidities, including cardiovascular morbidity. Recent studies suggest that certain arrhythmias may be more frequent in AS patients than in the general population. The aim of this study was to analyze the prevalence of electric heart disorders (EHD) in patients with AS in real-world conditions and compare them with those reported in the general population. Methods: Descriptive cross-sectional study aiming to determine the prevalence of EHD in AS in pre-COVID-19 period. EHD were analyzed in a resting ECG and 24 h Holter monitoring. Additionally, the association between clinical and demographic variables was analyzed. Results: Among 121 patients with AS (62% men; mean ± SD age 54.6 ± 15.6 years; median [IQR] disease duration 14 (8–20) years), 18.2% presented any EHD, including 9.1% with supraventricular tachyarrhythmias (SVT) (5% atrial fibrillation [AF]) and 7.4% with atrioventricular block (AVB). Clinically relevant disorders (≥2nd-degree AVB or SVT) were observed in 9.9% of patients. In adjusted analyses, SVT was independently associated with older age and higher BMI, while any conduction delay and clinically relevant EHD were associated with age, hypertension, and disease-modifying antirheumatic-drug treatment duration. Comparisons with previous population-based studies showed similar data, with a non-significant trend toward higher AF prevalence in AS patients. Conclusions: There appears to be a trend toward a higher prevalence of arrhythmias in patients with AS in real-world conditions, which could have clinical and therapeutic implications. An association between EHD and pro-inflammatory conditions such as age and BMI was observed, supporting the hypothesis that underlying inflammation might contribute to increased arrhythmogenicity. Full article