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Cardiac electrophysiology

Nagendra Madan Singh, T N Sathyaprabha, Kashyap Malthish, Jagadisha Thirthalli, Chittaranjan Andrade
BACKGROUND: Studies have examined the effects of electroconvulsive therapy (ECT) on human cardiac electrophysiology. However, no study has so far examined whether these effects vary with the magnitude of the electrical dose used to elicit the seizure. Because the benefits and adverse effects of the ECT seizure are dose-dependent, we examined the effects of different electrical doses of electroconvulsive shocks (ECS) on cardiac electrophysiology in an animal model with a view to determine whether cardiac electrophysiology could be a useful proxy to evaluate the quality of the ECT seizure...
March 2, 2018: Asian Journal of Psychiatry
Barbara Wiśniowska, Sebastian Polak
The current study is an example of drug-disease interaction modeling where a drug induces a condition which can affect the pharmacodynamics of other concomitantly taken drugs. The electrophysiological effects of hypokaliemia and heart rate changes induced by the antiasthmatic drugs were simulated with the use of the cardiac safety simulator. Biophysically detailed model of the human cardiac physiology-ten Tusscher ventricular cardiomyocyte cell model-was employed to generate pseudo-ECG signals and QTc intervals for 44 patients from four clinical studies...
March 15, 2018: Journal of Pharmacokinetics and Pharmacodynamics
Ibrahim El-Battrawy, Zhihan Zhao, Huan Lan, Xin Li, Gökhan Yücel, Siegfried Lang, Katherine Sattler, Jan-Dierk Schünemann, Wolfram-Hubertus Zimmermann, Lukas Cyganek, Jochen Utikal, Thomas Wieland, Karen Bieback, Ralf Bauer, Antonius Ratte, Regina Pribe-Wolferts, Kleopatra Rapti, Daniel Nowak, Janina Wittig, Dierk Thomas, Patrick Most, Hugo A Katus, Ursula Ravens, Constanze Schmidt, Martin Borggrefe, Xiao-Bo Zhou, Oliver J Müller, Ibrahim Akin
BACKGROUND: Limb-Girdle muscular dystrophies (LGMD) are a heritable group of genetically determined disorders with a primary involvement of the pelvic or shoulder girdle musculature with partially cardiac manifestation, such as dilated cardiomyopathy (DCM) and life-threatening tachyarrhythmia. We report here that human induced pluripotent stem cell (hiPSC)-derived cardiomyocytes from a patient with LGMD2I and DCM associated with recurrent ventricular tachycardia displayed ion channel dysfunction and abnormality of calcium homeostasis...
March 2018: Circ Genom Precis Med
Lucie Angel, Badiâa Bouazzaoui, Michel Isingrini, Séverine Fay, Laurence Taconnat, Sandrine Vanneste, Moïse Ledoux, Valérie Gissot, Caroline Hommet, Fréderic Andersson, Laurent Barantin, Jean-Philippe Cottier, Jérémy Pasco, Thomas Desmidt, Frédéric Patat, Vincent Camus, Jean-Pierre Remenieras
Aging is characterized by a cognitive decline of fluid abilities and is also associated with electrophysiological changes. The vascular hypothesis proposes that brain is sensitive to vascular dysfunction which may accelerate age-related brain modifications and thus explain age-related neurocognitive decline. To test this hypothesis, cognitive performance was measured in 39 healthy participants from 20 to 80 years, using tests assessing inhibition, fluid intelligence, attention and crystallized abilities. Brain functioning associated with attentional abilities was assessed by measuring the P3b ERP component elicited through an auditory oddball paradigm...
March 12, 2018: Brain and Cognition
Sha Yan, Pengfei Huang, Ying Wang, Xiongzhi Zeng, Yiya Zhang
Spider venoms are known to contain various toxins that are used as an effective means to capture their prey or to defend themselves against predators. An investigation of the properties of Ornithoctonus huwena (O.huwena) crude venom found that the venom can block neuromuscular transmission of isolated mouse phrenic nerve-diaphragm and sciatic nerve-sartorius preparations. However, little is known about its electrophysiological effects on cardiac myocytes. In this study, electrophysiological activities of ventricular myocytes were detected by 100 μg/mL venom of O...
March 13, 2018: Channels
Bence Hegyi, Julie Bossuyt, Leigh G Griffiths, Rafael Shimkunas, Zana Coulibaly, Zhong Jian, Kristin N Grimsrud, Claus S Sondergaard, Kenneth S Ginsburg, Nipavan Chiamvimonvat, Luiz Belardinelli, András Varró, Julius G Papp, Piero Pollesello, Jouko Levijoki, Leighton T Izu, W Douglas Boyd, Tamás Bányász, Donald M Bers, Ye Chen-Izu
Heart failure (HF) following myocardial infarction (MI) is associated with high incidence of cardiac arrhythmias. Development of therapeutic strategy requires detailed understanding of electrophysiological remodeling. However, changes of ionic currents in ischemic HF remain incompletely understood, especially in translational large-animal models. Here, we systematically measure the major ionic currents in ventricular myocytes from the infarct border and remote zones in a porcine model of post-MI HF. We recorded eight ionic currents during the cell's action potential (AP) under physiologically relevant conditions usingself AP-clamp sequential dissection...
March 12, 2018: Proceedings of the National Academy of Sciences of the United States of America
Naoko Yamaguchi, Kentaro Yamakawa, Pradeep S Rajendran, Tatsuo Takamiya, Marmar Vaseghi
BACKGROUND: Neuraxial modulation with cardiac sympathetic denervation (CSD) can potentially reduce burden of ventricular tachy-arryhthmias (VT). Despite catheter ablation and CSD, however, VT can recur in patients with cardiomyopathy and the role of vagal nerve stimulation (VNS) in this setting is unclear. OBJECTIVE: The purpose of this study was to evaluate electrophysiological effects of VNS after CSD in normal and infarcted hearts. METHODS: In 10 normal and 6 infarcted pigs, electrophysiological and hemodynamic parameters were evaluated before and during intermittent VNS pre-CSD (bilateral stellectomy and T2-T4 thoracic ganglia removal) as well as post-CSD...
March 9, 2018: Heart Rhythm: the Official Journal of the Heart Rhythm Society
Mengye Li, Karan R Chadda, Gareth D K Matthews, Celia M Marr, Christopher L-H Huang, Kamalan Jeevaratnam
Exercising horses uniquely accommodate 7-8-fold increases in heart rate (HR). The present experiments for the first time analysed the related adaptations in action potential (AP) restitution properties recorded by in vivo telemetric electrocardiography from Thoroughbred horses. The horses were subjected to a period of acceleration from walk to canter. The QRS durations, and QT and TQ intervals yielded AP conduction velocities, AP durations (APDs) and diastolic intervals respectively. From these, indices of active, λ = QT/(QRS duration), and resting, λ0 = TQ/(QRS duration), AP wavelengths were calculated...
2018: PloS One
Catherine E Lipovsky, Brittany D Brumback, Aditi Khandekar, Stacey L Rentschler
The left and right ventricles of the four-chambered heart have distinct developmental origins and functions. Chamber-specific developmental programming underlies the differential gene expression of ion channel subunits regulating cardiac electrophysiology that persists into adulthood. Here, we discuss regional specific electrical responses to genetic mutations and cardiac stressors, their clinical correlations, and describe many of the multi-scale techniques commonly used to analyze electrophysiological regional heterogeneity...
March 8, 2018: Journal of Cardiovascular Development and Disease
Hussein Nafakhi, Abdulameer A Al-Mosawi, Mohammed Alareedh, Hasan A Al-Nafakh
AIM: To assess the possible relationship between coronary atherosclerosis markers, pericardial fat volume (PFV) and coronary artery calcification, With ECG markers of index of the cardiac electrophysiological balance (iCEB) and transmural dispersion of the repolarization in patients with suspected coronary artery disease. METHODOLOGY: One hundred patients who underwent 64-slice multidetector computed tomography angiography were found to be eligible and were enrolled in the study...
March 8, 2018: Biomarkers in Medicine
Julia Dahlmann, George Awad, Carsten Dolny, Sönke Weinert, Karin Richter, Klaus-Dieter Fischer, Thomas Munsch, Volkmar Leßmann, Marianne Volleth, Martin Zenker, Yaoyao Chen, Claudia Merkl, Angelika Schnieke, Hassina Baraki, Ingo Kutschka, George Kensah
The possibility to generate cardiomyocytes from pluripotent stem cells in vitro has enormous significance for basic research, disease modeling, drug development and heart repair. The concept of heart muscle reconstruction has been studied and optimized in the rat model using rat primary cardiovascular cells or xenogeneic pluripotent stem cell derived-cardiomyocytes for years. However, the lack of rat pluripotent stem cells (rPSCs) and their cardiovascular derivatives prevented the establishment of an authentic clinically relevant syngeneic or allogeneic rat heart regeneration model...
2018: PloS One
Richard A Gray, Pras Pathmanathan
Patient-specific computer models have been developed representing a variety of aspects of the cardiovascular system spanning the disciplines of electrophysiology, electromechanics, solid mechanics, and fluid dynamics. These physiological mechanistic models predict macroscopic phenomena such as electrical impulse propagation and contraction throughout the entire heart as well as flow and pressure dynamics occurring in the ventricular chambers, aorta, and coronary arteries during each heartbeat. Such models have been used to study a variety of clinical scenarios including aortic aneurysms, coronary stenosis, cardiac valvular disease, left ventricular assist devices, cardiac resynchronization therapy, ablation therapy, and risk stratification...
March 6, 2018: Journal of Cardiovascular Translational Research
Prabhpreet Singh, Amit Noheria
Invasive electrophysiology (EP) mapping and catheter ablation has increasingly become the standard of care for many cardiac arrhythmias like supraventricular tachycardias, atrial fibrillation, premature ventricular complexes (PVC), and monomorphic ventricular tachycardia. In this review, we discuss the recent progress made in the mapping and ablation of ventricular fibrillation (VF). Ventricular activation during VF is apparently disorganized, making mapping and interpretation difficult. Prolonged mapping during VF would require mechanical circulatory support as VF causes complete hemodynamic collapse...
March 6, 2018: Current Treatment Options in Cardiovascular Medicine
Diana A Monteiro, Edwin W Taylor, Marina R Sartori, André L Cruz, Francisco T Rantin, Cleo A C Leite
The present study has revealed that the lungfish has both structural and functional features of its system for physiological control of heart rate, previously considered solely mammalian, that together generate variability (HRV). Ultrastructural and electrophysiological investigation revealed that the nerves connecting the brain to the heart are myelinated, conferring rapid conduction velocities, comparable to mammalian fibers that generate instantaneous changes in heart rate at the onset of each air breath...
February 2018: Science Advances
Jingqi Q X Gong, Eric A Sobie
Quantitative mismatches between human physiology and experimental models can be problematic for the development of effective therapeutics. When the effects of drugs on human adult cardiac electrophysiology are of interest, phenotypic differences with animal cells, and more recently stem cell-derived models, can present serious limitations. We addressed this issue through a combination of mechanistic mathematical modeling and statistical analyses. Physiological metrics were simulated in heterogeneous populations of models describing cardiac myocytes from adult ventricles and those derived from induced pluripotent stem cells (iPSC-CMs)...
2018: NPJ Systems Biology and Applications
Kirstine Calloe, Anders K Broendberg, Alex H Christensen, Lisbeth N Pedersen, Morten S Olesen, Maria de Los Angeles Tejada, Soren Friis, Morten B Thomsen, Henning Bundgaard, Henrik K Jensen
BACKGROUND: SCN5A mutations can lead to different cardiac diseases. Recently, SCN5A mutations have been linked to the clinical entity multifocal ectopic Purkinje-related premature contractions (MEPPC) characterized by ventricular ectopy and dilated cardiomyopathy. METHODS & RESULTS: A family with a uniform MEPPC-like phenotype, associated with complex atrial and ventricular arrhythmias and dilated cardiomyopathy caused by a high frequency of ventricular ectopy was clinically assessed...
April 15, 2018: International Journal of Cardiology
Pras Pathmanathan, Richard A Gray
Computational models of cardiac electrophysiology have a long history in basic science applications and device design and evaluation, but have significant potential for clinical applications in all areas of cardiovascular medicine, including functional imaging and mapping, drug safety evaluation, disease diagnosis, patient selection, and therapy optimisation or personalisation. For all stakeholders to be confident in model-based clinical decisions, cardiac electrophysiological (CEP) models must be demonstrated to be trustworthy and reliable...
2018: Frontiers in Physiology
Xi Yang, Thomas Papoian
Drug-induced cardiotoxicity is a potentially severe side effect that can adversely affect myocardial contractility through structural or electrophysiological changes in cardiomyocytes. Human-induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs) are a promising human cardiac in vitro model system to assess both proarrhythmic and non-proarrhythmic cardiotoxicity of new drug candidates. The scalable differentiation of hiPSCs into cardiomyocytes provides a renewable cell source that overcomes species differences present in current animal models of drug toxicity testing...
February 27, 2018: Journal of Applied Toxicology: JAT
Abraham Sonny, Brett J Wakefield, Shiva Sale, Stephanie Mick, Bruce L Wilkoff, Anand R Mehta
With increasing use of cardiovascular implantable electronic devices, the need for lead extractions has increased to an annual volume of more than 10,000 extractions worldwide. This article provides a focused clinical commentary on the perioperative management, identification, and treatment of life-threatening complications associated with lead extractions. In addition, a summary of indications, techniques, and lead extraction complications is provided. Although uncommon, lead extractions are associated with a consistent rate of major procedure-related complications and mortality...
January 10, 2018: Journal of Cardiothoracic and Vascular Anesthesia
Guang Yang, Xiahai Zhuang, Habib Khan, Shouvik Haldar, Eva Nyktari, Lei Li, Ricardo Wage, Xujiong Ye, Greg Slabaugh, Raad Mohiaddin, Tom Wong, Jennifer Keegan, David Firmin
PURPOSE: Atrial fibrillation (AF) is the most common heart rhythm disorder and causes considerable morbidity and mortality, resulting in a large public health burden that is increasing as the population ages. It is associated with atrial fibrosis, the amount and distribution of which can be used to stratify patients and to guide subsequent electrophysiology ablation treatment. Atrial fibrosis may be assessed non-invasively using late gadolinium-enhanced (LGE) magnetic resonance imaging (MRI) where scar tissue is visualised as a region of signal enhancement...
February 26, 2018: Medical Physics
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