scholarly journals MEASUREMENT OF QRS AND QTC DURATION AND DISPERSION PREDICTS VENTRICULAR ARRHYTHMIAS IN THE EARLY STAGE OF ACUTE MYOCARDIAL INFRACTION

2021 ◽  
Vol 11 (3) ◽  
pp. 309-316
Author(s):  
Aram J. Mirza ◽  
◽  
Farman J. Ahmed ◽  
Hemn H. Mohammad ◽  
◽  
...  
Keyword(s):  
Ventricular Arrhythmias ◽  
Early Stage ◽  
Myocardial Infraction

scholarly journals Ion Channel Impairment and Myofilament Ca2+ Sensitization: Two Parallel Mechanisms Underlying Arrhythmogenesis in Hypertrophic Cardiomyopathy

Cells ◽  
2021 ◽  
Vol 10 (10) ◽  
pp. 2789
Author(s):  
Lorenzo Santini ◽  
Raffaele Coppini ◽  
Elisabetta Cerbai
Keyword(s):  
Hypertrophic Cardiomyopathy ◽  
Ventricular Arrhythmias ◽  
Early Stage ◽  
Sodium Current ◽  
Young Patients ◽  
Early Observation ◽  
Parallel Mechanisms ◽  
Cellular Mechanisms ◽  
Increased Risk ◽  
Repolarization Reserve

Life-threatening ventricular arrhythmias are the main clinical burden in patients with hypertrophic cardiomyopathy (HCM), and frequently occur in young patients with mild structural disease. While massive hypertrophy, fibrosis and microvascular ischemia are the main mechanisms underlying sustained reentry-based ventricular arrhythmias in advanced HCM, cardiomyocyte-based functional arrhythmogenic mechanisms are likely prevalent at earlier stages of the disease. In this review, we will describe studies conducted in human surgical samples from HCM patients, transgenic animal models and human cultured cell lines derived from induced pluripotent stem cells. Current pieces of evidence concur to attribute the increased risk of ventricular arrhythmias in early HCM to different cellular mechanisms. The increase of late sodium current and L-type calcium current is an early observation in HCM, which follows post-translation channel modifications and increases the occurrence of early and delayed afterdepolarizations. Increased myofilament Ca2+ sensitivity, commonly observed in HCM, may promote afterdepolarizations and reentry arrhythmias with direct mechanisms. Decrease of K+-currents due to transcriptional regulation occurs in the advanced disease and contributes to reducing the repolarization-reserve and increasing the early afterdepolarizations (EADs). The presented evidence supports the idea that patients with early-stage HCM should be considered and managed as subjects with an acquired channelopathy rather than with a structural cardiac disease.

scholarly journals Evidence of Ventricular Arrhythmogenicity and Cardiac Sympathetic Hyperinnervation in Early Cirrhotic Cardiomyopathy

2021 ◽  
Vol 12 ◽  
Author(s):  
Shin-Huei Liu ◽  
Li-Wei Lo ◽  
Yu-Hui Chou ◽  
Wei-Lun Lin ◽  
Tsung-Ying Tsai ◽  
...  
Keyword(s):  
Ventricular Arrhythmias ◽  
Sham Group ◽  
Early Stage ◽  
Sympathetic Innervation ◽  
Rabbit Model ◽  
Sympathetic Nerves ◽  
Structural Heterogeneity ◽  
Close Monitoring ◽  
Cirrhotic Cardiomyopathy ◽  
The Common

Cirrhotic cardiomyopathy (CMP) is associated with altered cardiac electrophysiological (EP) properties, which leads to the risk of ventricular arrhythmias (VAs). We aimed to evaluate the EP properties, autonomic, and structural remodeling in a rabbit model with early liver cirrhosis (LC). Twelve rabbits were assigned to the sham and LC groups. The early-stage LC was induced by the ligation of the common bile duct. All rabbits received an EP study, VA inducibility test, myocardial, and liver histology staining. Western blot analyses of protein expression and tyrosine hydroxylase stain for sympathetic nerves were performed. The effective refractory period the LC group was significantly longer than the sham group [i.e., left ventricle (LV) 205.56 ± 40.30 vs. 131.36 ± 7.94 ms; right ventricle (RV) 206.78 ± 33.07 vs. 136.79 ± 15.15 ms; left atrium (LA) 140.56 ± 28.75 vs. 67.71 ± 14.29 ms; and right atrium (RA) 133.78 ± 40.58 vs. 65.43 ± 19.49 ms, all p < 0.01], respectively. The VA inducibility was elevated in the LC group when compared with the sham group (i.e., 21.53 ± 7.71 vs. 7.76 ± 2.44%, p = 0.013). Sympathetic innervation (102/μm2/mm2) was increased in all cardiac chambers of the LC group compared with the sham group (i.e., LV 9.11 ± 4.86 vs. 0.17 ± 0.15, p < 0.01; RV 4.36 ± 4.95 vs. 0.18 ± 0.12, p = 0.026; LA 6.79 ± 1.02 vs. 0.44 ± 0.20, p = 0.018; and RA 15.18 ± 5.12 vs. 0.10 ± 0.07, p = 0.014), respectively. Early LC is presented with an increased ventricular vulnerability, structural heterogeneity, and sympathetic innervation. Close monitoring for fatal arrhythmias is warranted in patients with early stages of LC.

scholarly journals Development of a specific troponin I detection system with enhanced immune sensitivity using a single monoclonal antibody

2020 ◽  
Vol 7 (10) ◽  
pp. 200871
Author(s):  
Anıl Bozdogan ◽  
Reham F. El-Kased ◽  
Vanessa Jungbluth ◽  
Wolfgang Knoll ◽  
Jakub Dostalek ◽  
...  
Keyword(s):  
Monoclonal Antibody ◽  
Surface Plasmon ◽  
Troponin I ◽  
Limit Of Detection ◽  
Detection System ◽  
Early Stage ◽  
Complex Form ◽  
Heart Attacks ◽  
Myocardial Infraction ◽  
20 Nm

Using an immunoassay in combination with surface plasmon fluorescence spectroscopy (SPFS), we report the rapid detection of troponin I, a valuable biomarker for diagnosis of myocardial infarction. We discuss the implementation of (i) direct, (ii) sandwich, and (iii) competitive assay formats, based on surface plasmon resonance and SPFS. To elucidate the results, we relate the experiments to orientation-dependent interaction of troponin I epitopes with respective immunoglobulin G antibodies. A limit of detection (LoD) of 19 pM, with 45 min readout time, was achieved using single monoclonal antibody that is specific for one epitope. The borderline between normal people and patients is 20 pM to 83 pM cTnI concentration, and upon the outbreak of acute myocardial infraction it can raise to 2 nM and levels at 20 nM for 6–8 days, therefore the achieved LoD covers most of the clinically relevant range. In addition, this system allows for the detection of troponin I using a single specific monoclonal antibody, which is highly beneficial in case of detection in real samples, where the protein has a complex form leading to hidden epitopes, thus paving the way towards a system that can improve early-stage screening of heart attacks.

scholarly journals Vagus Nerve Stimulation in Early Stage of Acute Myocardial Infarction Prevent Ventricular Arrhythmias and Cardiac Remodeling

2021 ◽  
Vol 8 ◽  
Author(s):  
Shuang Zhao ◽  
Yan Dai ◽  
Xiaohui Ning ◽  
Min Tang ◽  
Yunzi Zhao ◽  
...  
Keyword(s):  
Gene Expression ◽  
Myocardial Infarction ◽  
Left Ventricular Function ◽  
Ventricular Function ◽  
Nerve Stimulation ◽  
Vagus Nerve Stimulation ◽  
Ventricular Arrhythmias ◽  
Early Stage ◽  
Left Ventricular ◽  
Nerve Sprouting

Aims: To evaluate whether low level left vagus nerve stimulation (LLVNS) in early stage of myocardial infarction (MI) could effectively prevent ventricular arrhythmias (VAs) and protect cardiac function, and explore the underlying mechanisms.Methods and Results: After undergoing implantable cardioverter defibrillators (ICD) and left cervical vagal stimulators implantation and MI creation, 16 dogs were randomly divided into three groups: the MI (n = 6), MI+LLVNS (n = 5), and sham operation (n = 5) groups. LLVNS was performed for 3 weeks. VAs, the left ventricular function, the density of the nerve fibers in the infarction area and gene expression profiles were analyzed. Compared with the MI group, dogs in the MI+LLVNS group had a lower VAs incidence (p < 0.05) and better left ventricular function. LLVNS significantly inhibited excessive sympathetic nerve sprouting with the evidences of decreased density of TH, GAP43 and NF positive nerves (p < 0.05). The gene expression profiling found a total of 206 genes differentially expressed between MI+LLVNS and MI dogs, mainly involved in cardiac tissue remodeling, cardiac neural remodeling, immune response and apoptosis. These genes, including 55 up-regulated genes and 151 down-regulated genes, showed more protective expressions under LLVNS.Conclusions: This study suggests that LLVNS was delivered without altering heart rate, contributing to reduced incidences of VAs and improved left ventricular function. The potential mechanisms included suppressing cardiac neuronal sprouting, inhibiting excessive sympathetic nerve sprouting and subduing pro-inflammatory responses by regulating gene expressions from a canine experimental study.

scholarly journals Malignant Ventricular Arrhythmias After Surgery for Uncomplicated Congenital Atrial Septal Defect-Case Report

2020 ◽  
Author(s):  
Ying Liang ◽  
Yulong Guan
Keyword(s):  
Congenital Heart Disease ◽  
Heart Disease ◽  
Case Report ◽  
Atrial Septal Defect ◽  
Ventricular Arrhythmias ◽  
Congenital Heart ◽  
Septal Defect ◽  
Early Stage ◽  
Uneventful Recovery ◽  
Case Presentation

Abstract Background:Malignant ventricular arrhythmias (MVA) occurring subsequent to a repair of uncomplicated congenital heart disease is scarcely described in literature.Case presentation:One adult patient following congenital atrial septal defect (ASD) repair underwent immediate postoperative refractory MAV and ventricular fibrillation. The recurrent episodes of shocks cannot be suppressed by drugs. Emergent re-exploration was performed and repeated closure of ASD and DeVega's annuloplasty were completed. The patient had uneventful recovery and no occurrence of arrhythmia.Conclusion: Malignant ventricular arrhythmias are rare and should never be overemphasized even during the repair of uncomplicated congenital heart defect. Re-exploration should be taken into consideration when MVA occurred in the early stage postoperatively.

Alterations in the number of motoneurons containing immunoreactive calcitonin gene-related peptide(CGRP)& choline acetyltransferase(ChAT) in the cervical spinal cord of the wobbler mouse during the development of the motoneuron disease

1995 ◽  
Vol 53 ◽  
pp. 970-971
Author(s):  
L. Vacca-Galloway ◽  
Y.Q. Zhang ◽  
P. Bose ◽  
S.H. Zhang
Keyword(s):  
Spinal Cord ◽  
Early Stage ◽  
Cervical Spinal Cord ◽  
Wild Type Mouse ◽  
Reflex Response ◽  
Mouse Strains ◽  
Behavioral Tests ◽  
Wobbler Mouse ◽  
Stage 4 ◽  
Stage 1

The Wobbler mouse (wr) has been studied as a model for inherited human motoneuron diseases (MNDs). Using behavioral tests for forelimb power, walking, climbing, and the “clasp-like reflex” response, the progress of the MND can be categorized into early (Stage 1, age 21 days) and late (Stage 4, age 3 months) stages. Age-and sex-matched normal phenotype littermates (NFR/wr) were used as controls (Stage 0), as well as mice from two related wild-type mouse strains: NFR/N and a C57BI/6N. Using behavioral tests, we also detected pre-symptomatic Wobblers at postnatal ages 7 and 14 days. The mice were anesthetized and perfusion-fixed for immunocytochemical (ICC) of CGRP and ChAT in the spinal cord (C3 to C5).Using computerized morphomety (Vidas, Zeiss), the numbers of IR-CGRP labelled motoneurons were significantly lower in 14 day old Wobbler specimens compared with the controls (Fig. 1). The same trend was observed at 21 days (Stage 1) and 3 months (Stage 4). The IR-CGRP-containing motoneurons in the Wobbler specimens declined progressively with age.

Automated high-resolution microscopy: the approaches so far

1987 ◽  
Vol 45 ◽  
pp. 58-61
Author(s):  
W. O. Saxton
Keyword(s):  
High Resolution ◽  
Early Stage ◽  
Automatic Recording ◽  
Microprocessor Control ◽  
Alternative Systems ◽  
Electron Image ◽  
Complete Automation ◽  
Analysis System ◽  
High Resolution Microscopy

Recent commercial microscopes with internal microprocessor control of all major functions have already demonstrated some of the benefits anticipated from such systems, such as continuous magnification, rotation-free diffraction and magnification, automatic recording of mutually registered focal series, and fewer control knobs. Complete automation of the focusing, stigmating and alignment of a high resolution microscope, allowing focal series to be recorded at preselected focus values as well, is still imminent rather than accomplished, however; some kind of image pick-up and analysis system, fed with the electron image via a TV camera, is clearly essential for this, but several alternative systems and algorithms are still being explored. This paper reviews the options critically in turn, and stresses the need to consider alignment and focusing at an early stage, and not merely as an optional extension to a basic proposal.

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