("ECG" OR "EKG") AND ("Block")

The anatomy of the His-Purkinje system has been studied, yet there remains a knowledge gap regarding the impact of His bundle pacing and its electrocardiographic implications. This case report highlights the presence of His-Purkinje system pathology without apparent clues on the surface electrocardiogram (EKG). By observing identical QRS morphology with varying HV intervals resulting from different pacing outputs, we demonstrate the presence of an electrical propagation block within the His bundle.

BACKGROUND: Dilated cardiomyopathy (DCM) commonly leads to heart failure (HF) and represents the most common indication for cardiac transplantation in the pediatric population. Clinical manifestations of DCM are mainly the symptoms of heart failure; it is diagnosed by EKG, chest x-ray and echocardiography. For the idiopathic and familial diseases cases of DCM, there are no definite guidelines for treatment in children as they are treated for prognostic improvement. CASE PRESENTATION: We report the case of a 2-year-old girl diagnosed with dilated cardiomyopathy associated with homozygous mutation in the Myosin Light Chain 3 gene admitted for edema in lower extremities, muscle weakness, lethargy and vomiting, and she was found to be in cardiogenic shock...

Heart rate variability analyses using Poincaré plots can be useful for evaluating the autonomic nervous system function. However, the interpretation of the quantitative indicators of Poincaré plots remains controversial. Thus, few studies have verified the effectiveness of the quantitative indicators in veterinary medicine. This study aimed to verify the reliability of Poincaré plot indicators using pharmacological models in dogs. Four healthy beagles were used in this study...

The adoption of Industry 4.0 technologies in manufacturing systems has accelerated in recent years, with a shift towards understanding operators' well-being and resilience within the context of creating a human-centric manufacturing environment. In addition to measuring physical workload, monitoring operators' cognitive workload is becoming a key element in maintaining a healthy and high-performing working environment in future digitalized manufacturing systems. The current approaches to the measurement of cognitive workload may be inadequate when human operators are faced with a series of new digitalized technologies, where their impact on operators' mental workload and performance needs to be better understood...

Defined as systemic hypotension caused by intense vasodilation due to the loss of systemic vascular resistance, vasoplegic syndrome (VS) is associated with elevated morbidity and mortality in humans. Although vasopressors such as norepinephrine and vasopressin are the first-choice drugs for VS treatment, several other drugs such as methylene blue (MB) can be used as adjuvant therapy including rescue therapy. To develop new pharmacological strategies to reduce the risk of VS, we investigated the effects of treatments with MB (2 mg/kg/IV), omeprazole (OME, 10 mg/kg/IV), and their combination in an animal model of cardiac ischemia-reperfusion (CIR)...

IMPORTANCE: Current left bundle branch block (LBBB) criteria are based on animal experiments or mathematical models of cardiac tissue conduction and may misclassify patients. Improved criteria would impact referral decisions and device type for cardiac resynchronization therapy. OBJECTIVE: To develop a simple new criterion for LBBB based on electrophysiological studies of human patients, and then to validate this criterion in an independent population. DESIGN, SETTING, AND PARTICIPANTS: In this diagnostic study, the derivation cohort was from a single-center, prospective study of patients undergoing electrophysiological study from March 2016 through November 2019...

3DQRSarea is a strong marker for cardiac resynchronization therapy and can be obtained by taking the (i) summation or the (ii) difference of the areas subtended by positive and negative deflections in X, Y, Z vectorcardiographic electrocardiogram (ECG) leads. We correlated both methods with the instantaneous-absolute-3D-voltage-time-integral (VTIQRS-3D ). 3DQRSarea consistently underestimated the VTIQRS -3D , but the summation method was a closer and more reliable approximation. The dissimilarity was less apparent in left bundle branch block (r2 summation ...

Objective: To summarize the clinical manifestations, experiences in diagnosis and treatment of arrhythmogenic cardiomyopathy (ACM) in children. Methods: A retrospective analysis of the clinical manifestations, laboratory tests, radiological features, treatment and follow-up results was conducted in 11 children diagnosed with ACM at the center of congenital heart disease, Beijing anzhen hospital from May 2010 to March 2022. Results: A total of 11 patients aged 2 to 16 years, including 5 males and 6 females were diagnosed with ACM...

BACKGROUND: Refractory secondary hyperparathyroidism (SHPT) is a common complication observed in patients with end-stage renal disease and can result in ectopic calcification. Metastatic calcification involving the heart valves and the conduction system can easily lead to arrhythmias, including atrioventricular block. This case report describes a maintenance hemodialysis patient with refractory SHPT resulting in a complete atrioventricular block (CAVB), which was eventually reversed to a first-degree atrioventricular block...

Bradycardia, renal failure, atrioventricular (AV) block, shock, and hyperkalemia (BRASH) syndrome is a rare clinical entity that poses challenges for healthcare practitioners. It is characterized by bradycardia, renal failure, atrioventricular (AV) obstruction, shock, and hyperkalemia. This case is an interesting instance of BRASH syndrome in the setting of COVID-19 infection and end-stage renal disease (ESRD). Initial laboratory results revealed macrocytic anemia, renal dysfunction, acidosis, and mild hyponatremia, along with hyperkalemia...

Transient left bundle branch block occurring during a nuclear stress test in the setting of myocardial bridging is a relatively rare finding. We report a case of a 75-year-old male who presented with typical stable angina. Serial troponins were negative, and the electrocardiogram revealed normal sinus rhythm with left ventricular hypertrophy and T-wave inversions in the lateral leads. The nuclear stress test was non-ischemic but showed a transient left bundle branch block associated with chest pain and shortness of breath that occurred right after the administration of regadenoson...

BACKGROUND: Myocardial infarction (MI) is one of the most deadly diseases in the world. Hyperoside (Hyp) has been shown to have a protective effect on cardiovascular function through various signaling pathways, but whether it can protect myocardial infarction by regulating JAK2/STAT3 signaling pathway is unknown. AIM OF THE STUDY: To investigate whether Hyp could protect the heart against myocardial infarction injury in mice by modulating JAK2/STAT3 signaling pathway and its potential mechanism...

BACKGROUND: The ability to perform transvenous temporary cardiac pacing (TV-TP) is critical to stabilize horses with symptomatic bradyarrhythmias. Reports of successful TV-TP in horses are limited, and only briefly describe short-term pacing. OBJECTIVE: To describe temporary, medium-term (24 h) transvenous right ventricular pacing in awake horses using a bipolar torque-directed pacing catheter. ANIMALS: Six healthy adult institutional teaching horses...

BACKGROUND: Implantable loop recorders (ILR) are increasingly used to evaluate patients with unexplained syncope. Identification of all predictors of bradycardic syncope and consequent permanent pacemaker (PPM) insertion is of substantial clinical interest, as patients in the highest-risk category may benefit from upfront pacemaker insertion. OBJECTIVES: We performed a systematic review and meta-analysis to identify risk predictors for PPM insertion in ILR recipients with unexplained syncope...

BACKGROUND AND OBJECTIVES: Although a single-lead electrocardiogram (ECG) patch may provide advantages for detecting arrhythmias in outpatient settings owing to user convenience, its comparative effectiveness for real-time telemonitoring in inpatient settings remains unclear. We aimed to compare a novel telemonitoring system using a single-lead ECG patch with a conventional telemonitoring system in an inpatient setting. METHODS: This was a single-center, prospective cohort study...

Torsades de Pointes (TdP) refers to a polymorphic ventricular tachycardia (VT) with undulating QRS axis that occurs in long QT syndrome (LQTS), although the term has been used to describe polymorphic ventricular tachyarrhythmias in which QT intervals are not prolonged, such as short-coupled variant of TdP currently known as short-coupled ventricular fibrillation (VF) and Brugada syndrome. Extensive works on LQTS-related TdP over more than 50 years since it was first recognized by Dessertennes who coined the French term meaning "twisting of the points", have led to current understanding of the electrophysiological mechanism that TdP is initiated by triggered activity due to early afterdepolarization (EAD) and maintained by reentry within a substrate of inhomogeneous repolarization...

BACKGROUND: We assessed the prevalence and diagnostic value of ECG abnormalities for cardiomyopathy surveillance in childhood cancer survivors. METHODS: In this cross-sectional study, 1381 survivors (≥5 years) from the Dutch Childhood Cancer Survivor Study part 2 and 272 siblings underwent a long-term follow-up ECG and echocardiography. We compared ECG abnormality prevalences using the Minnesota Code between survivors and siblings, and within biplane left ventricular ejection fraction (LVEF) categories...

OBJECTIVES: To examine the relationship of QRS voltages and left ventricular (LV) mass across the spectrum of individuals with different LV mass. METHODS: Twenty QRS voltage measurements or combinations were determined in a consecutive series of 159 adults with an ECG and echocardiogram without previous myocardial infarction, left or right bundle branch block, pre-excitation, or electronic pacemaker. RESULTS: The four strongest and significant correlations between QRS and LV mass were S in V4, deepest S wave in any precordial lead plus S in V4, S in V3, and S in V3 plus R in AVL times QRS duration...

Intermittent left bundle branch block (LBBB) is an unusual phenomenon, with very few cases documented in the literature. It is often considered a reflection of underlying conditions known to increase the risk of cardiovascular morbidity and death, including coronary artery disease (CAD), cardiomyopathy, hypertensive heart disease, and aortic valve disease. In rare instances, coronary vasospasm is the sole underlying condition. It is typically diagnosed by ECG and managed according to the underlying cause. We describe a case of intermittent LBBB presenting with chest pain...

OBJECTIVE: To explore the application of serum cardiac troponin T (cTnT), brain natriuretic peptide (BNP) levels, and electrocardiogram changes in the treatment and prognosis evaluation of severe pneumonia in children. METHODS: 120 children with severe pneumonia (severe group) admitted to our hospital from June 2020 to December 2022 were selected as the study subjects with prospective study. They were divided into survival group (n=78) and death group (n=42) based on their survival status; 120 children with mild pneumonia were selected as the control group...