Download or read book Recent Advances in Understanding the Basic Mechanisms of Atrial Fibrillation Using Novel Computational Approaches written by Jichao Zhao and published by Frontiers Media SA. This book was released on 2019-11-25 with total page 413 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Applying Computational Approaches to the Understanding of the Consequences and Opportunities of Ion Channel Properties in Atrial Fibrillation written by Martin Aguilar and published by . This book was released on 2019 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Cardiac arrhythmias are disorders of the electrical system of the heart and an often clinically-challenging group of disorders. Atrial fibrillation (AF) is the most common cardiac arrhythmia in the general population; it is associated with significant morbidity and mortality. Available antiarrhythmic drugs (AADs) for the treatment of AF are older molecules with sub- optimal efficacy and safety profiles. Recent advances in basic electrophysiology and the development of sophisticated mathematical modeling approaches could help in expanding our understanding of the basic mechanisms of AF and assist in the development of novel AF- selective AADs. The purpose of this thesis was to utilize computational approaches to the understanding of the consequences and opportunities of ion channel properties, with a special emphasis on AF. The cardiac action potential is the basic functional unit of the electrical system of the heart and is the manifestation of coordinated current fluxes through specialized proteins known as ion channels. Antiarrhythmic drugs act through modulation of ion channel properties. We hypothesized that mathematical modeling could be used to study and optimize the pharmacodynamic properties of AADs for the treatment of AF. We demonstrated that the pharmacodynamic properties (binding/unbinding characteristics) of a state-dependent Na+- channel blocker modulate the drug's anti-/proarrhythmic actions with inactivated-state blockers being optimally AF-selective. The optimized drug's selectivity for AF was the result of its rate- selectivity (stronger effects at fast vs slow cardiomyocyte activation rates) with relatively mild atrial-selective (stronger effects in atrial vs ventricular cardiomyocytes) actions. We found that the optimally AF-selective Na+-channel blocker had sub-optimal anti-AF efficacy, but that slightly less selective drugs had favorable AF-termination rates. We then sought to explore potential current-block combinations with synergistic AF- selective properties. Using mathematical modeling and laboratory experiments, we demonstrated that the combination of optimized state-dependent Na+-channel block and K+- channel block had synergistic effects, significantly augmenting AF termination rates for any level of AF-selectivity vs pure Na+-channel block. The mechanisms of these synergistic effects were found to be mediated by the functional interaction between the action potential prolonging- v effects of K+-channel block, the Na+-channel blocker's voltage-dependent binding/unbinding properties and the Na+ channel's inactivation characteristics, highlighting the non-linear nature of the cardiac action potential's dynamics. Traditional K+ currents targeted by AADs have significant ventricular proarrhythmic liabilities. Using recent experimental observations, we updated the mathematic formulation for the inactivation dynamics of the ultra-rapid delayed-rectifier K+ current (IKur), an atrial-specific current. Using this model, we showed that, contrary to what had been proposed in the published literature, IKur rate-dependent properties are mediated by its activation properties with minimal contribution from inactivation, under physiological conditions. We also demonstrated that the contribution of IKur to action potential repolarization is preserved, or even increased, in the setting of electrical remodeling-induced IKur downregulation. Finally, we described the mechanisms of the forward rate-dependent of IKur block, mediated by functional non-linear interactions with the rapid delayed inward-rectifier K+ current (IKr), the only K+ current with such properties. Until recently, fibroblasts were considered to be electrically inactive. More recently, experimental work demonstrated the presence of functional ionic current on the fibroblast and possible cardiomyocyte-fibroblast coupling. Here, we described a novel kind of heart failure- induced electrical remodeling involving the fibroblasts ion channels. This was characterized by downregulation of the fibroblast voltage-dependent K+ current (IKv,fb) and upregulation of the fibroblast inward-rectifier K+ current (IKir,fb). We then implemented our experimental findings into a mathematical model of cardiomyocyte-fibroblast coupling and found fibroblast electrical remodeling to have significant effects on the cardiomyocyte's electrophysiological properties. In a 2-dimension model of simulated AF, downregulation of IKv,fb had an antiarrhythmic effect whereas IKir,fb upregulation was found to be proarrhythmic. The studies presented here utilized mathematical modeling to study non-linear systems in cardiac electrophysiology to tackle questions that would have been difficult to approach with traditional laboratory-based experimentation. They also showcased how theoretical results can help orient and receive confirmation with subsequent experimental work or, conversely, novel experimental findings results be implemented into a mathematical model to investigate potential consequences. Mathematical modeling is a promising tool to help in studying the complex and vi non-linear effects of pharmacological modulation of ion channel properties and assist in the development of optimized antiarrhythmics for the treatment of AF, a major unmet need in clinical medicine. As models increase in sophistication to better represent the cardiomyocyte's electrophysiology, they will almost certainly play an ever-growing role in expanding our understanding of the mechanisms of complex arrhythmias.

Download or read book Exploring Mechanisms of Cardiac Rhythm Disturbances Using Novel Computational Methods Prediction Classification and Therapy written by Xin Li and published by Frontiers Media SA. This book was released on 2023-03-16 with total page 232 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Diagnosis Monitoring and Treatment of Heart Rhythm New Insights and Novel Computational Methods written by Jieyun Bai and published by Frontiers Media SA. This book was released on 2023-09-13 with total page 379 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Atrial Fibrillation Technology for Diagnosis Monitoring and Treatment written by Jose F. Rodriguez Matas and published by Frontiers Media SA. This book was released on 2022-03-15 with total page 537 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Electrocardiographic Imaging written by Maria S. Guillem and published by Frontiers Media SA. This book was released on 2020-04-17 with total page 178 pages. Available in PDF, EPUB and Kindle. Book excerpt: Electrical activity in the myocardium coordinates the contraction of the heart, and its knowledge could lead to a better understanding, diagnosis, and treatment of cardiac diseases. This electrical activity generates an electromagnetic field that propagates outside the heart and reaches the human torso surface, where it can be easily measured. Classical electrocardiography aims to interpret the 12-lead electrocardiogram (ECG) to determine cardiac activity and support the diagnosis of cardiac pathologies such as arrhythmias, altered activations, and ischemia. More recently, a higher number of leads is used to reconstruct a more detailed quantitative description of the electrical activity in the heart by solving the so-called inverse problem of electrocardiography. This technique is known as ECG imaging. Today, clinical applications of ECG imaging are showing promising results in guiding a variety of electrophysiological interventions such as catheter ablation of atrial fibrillation and ventricular tachycardia. However, in order to promote the adoption of ECG imaging in the routine clinical practice, further research is required regarding more accurate mathematical methods, further scientific validation under different preclinical scenarios and a more extensive clinical validation

Download or read book Molecular Mechanism of Congenital Heart Disease and Pulmonary Hypertension written by Toshio Nakanishi and published by Springer Nature. This book was released on 2020-02-28 with total page 374 pages. Available in PDF, EPUB and Kindle. Book excerpt: This open access book focuses on the molecular mechanism of congenital heart disease and pulmonary hypertension, offering new insights into the development of pulmonary circulation and the ductus arteriosus. It describes in detail the molecular mechanisms involved in the development and morphogenesis of the heart, lungs and ductus arteriosus, covering a range of topics such as gene functions, growth factors, transcription factors and cellular interactions, as well as stem cell engineering technologies. The book also presents recent advances in our understanding of the molecular mechanism of lung development, pulmonary hypertension and molecular regulation of the ductus arteriosus. As such, it is an ideal resource for physicians, scientists and investigators interested in the latest findings on the origins of congenital heart disease and potential future therapies involving pulmonary circulation/hypertension and the ductus arteriosus.

Download or read book The ESC Textbook of Cardiovascular Medicine written by European Society of Cardiology and published by Oxford University Press, USA. This book was released on 2009-08-27 with total page 1423 pages. Available in PDF, EPUB and Kindle. Book excerpt: Following the structure and format of the ESC core syllabus, this text introduces key concepts in the field of cardiovascular medicine.

Download or read book Recent Advances in Cardiotoxicity Testing written by Tamer M. A. Mohamed and published by Frontiers Media SA. This book was released on 2022-01-05 with total page 142 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Methods and Applications Computational Genomics written by Guanglin Li and published by Frontiers Media SA. This book was released on 2022-07-28 with total page 489 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Encyclopedia of Cell Biology written by and published by Academic Press. This book was released on 2015-08-07 with total page 2972 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Encyclopedia of Cell Biology, Four Volume Set offers a broad overview of cell biology, offering reputable, foundational content for researchers and students across the biological and medical sciences. This important work includes 285 articles from domain experts covering every aspect of cell biology, with fully annotated figures, abundant illustrations, videos, and references for further reading. Each entry is built with a layered approach to the content, providing basic information for those new to the area and more detailed material for the more experienced researcher. With authored contributions by experts in the field, the Encyclopedia of Cell Biology provides a fully cross-referenced, one-stop resource for students, researchers, and teaching faculty across the biological and medical sciences. Fully annotated color images and videos for full comprehension of concepts, with layered content for readers from different levels of experience Includes information on cytokinesis, cell biology, cell mechanics, cytoskeleton dynamics, stem cells, prokaryotic cell biology, RNA biology, aging, cell growth, cell Injury, and more In-depth linking to Academic Press/Elsevier content and additional links to outside websites and resources for further reading A one-stop resource for students, researchers, and teaching faculty across the biological and medical sciences

Download or read book Cardiac Electrophysiology Methods and Models written by Daniel C. Sigg and published by Springer Science & Business Media. This book was released on 2010-09-11 with total page 490 pages. Available in PDF, EPUB and Kindle. Book excerpt: Cardiovascular disease is the major cause of mortality and morbidity in the Western Hemisphere. While significant progress has been made in treating a major sub-category of cardiac disease, arrhythmias, significant unmet needs remain. In particular, every day, thousands of patients die because of arrhythmias in the US alone, and atrial fibrillation is the most common arrhythmia affecting millions of patients in the US alone at a given time. Therefore, there is a public need to continue to develop new and better therapies for arrhythmias. Accordingly, an ever increasing number of biomedical, pharmaceutical, and medical personnel is interested in studying various aspects of arrhythmias at a basic, translational, and applied level, both in industry (ie Biotech, Pharmaceutical and device), and in academia. Not only has our overall understanding of molecular bases of disease dramatically increased, but so has the number of available and emerging molecular, pharmacological or device treatment based therapies. This practical, state-of-the art handbook will summarize and review key research methods and protocols, their advantages and pitfalls, with a focus on practical implementation, and collaborative cross-functional research. The volume will include visual and easy-to-use graphics, bulleted summaries, boxed summary paragraphs, links to reference websites, equipment manufacturers where appropriate, photographs of typical experimental setups and so forth, to keep this book very focused on practical methods and implementation, and yet, provide enough theory that the principles are clearly understood and can be easily applied.

Download or read book Goldman Cecil Medicine E Book written by Lee Goldman and published by Elsevier Health Sciences. This book was released on 2015-04-21 with total page 4123 pages. Available in PDF, EPUB and Kindle. Book excerpt: Since 1927, Goldman-Cecil Medicine has been the world’s most influential internal medicine resource. In the ground-breaking 25th edition, your original purchase ensures you will be up-to-date without the need for a subscription. Through the new, more powerful Expert Consult eBook platform, this "living text" provides continuous updates that will integrate the latest research, guidelines, and treatments into each chapter, ensuring that the content is as current as the day this edition was first published. Goldman-Cecil Medicine offers definitive, unbiased guidance on the evaluation and management of every medical condition, presented by a veritable "Who's Who" of modern medicine. A practical, straightforward style; templated organization; evidence-based references; and robust interactive content combine to make this dynamic resource quite simply the fastest and best place to find all of the authoritative, state-of-the-art clinical answers you need. Expert Consult eBook version included with print purchase: Access continuous updates from Editor Lee Goldman, MD, who thoroughly reviews internal medicine and specialty journals, updating online content to reflect the latest guidelines and translating that evidence into treatment. Interactive Q&A section features over 1,500 board-style questions and answers to aid in preparing for certification or recertification exams. Outstanding supplementary tools include figures, tables, videos, heart and lung sounds, treatment and management algorithms, fully integrated references, and thousands of illustrations and full-color photos. Search all of the text, figures, supplementary material, and references from the book on a variety of devices and at no additional cost — Expert Consult access is included with this title! Practical, bulleted, highly templated text with easy-to-use features including flow charts and treatment boxes. New chapters on global health, cancer biology and genetics, and the human microbiome in health and disease keep you on the cutting edge of medicine. Today's most current evidence-based medicine guidelines help you form a definitive diagnosis and create the best treatment plans possible. Focused coverage of the latest developments in biology includes the specifics of current diagnosis, therapy, and medication doses. The reference of choice for every stage of your career! Goldman-Cecil Medicine is an ideal learning tool for residents, physicians, and students as well as a valuable go-to resource for experienced healthcare professionals.

Download or read book Risk Stratification Strategies for Cardiac Rhythm Abnormalities written by N A and published by Frontiers Media SA. This book was released on 2022-05-23 with total page 483 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Clinical Cardiac Pacing Defibrillation and Resynchronization Therapy E Book written by Kenneth A. Ellenbogen and published by Elsevier Health Sciences. This book was released on 2016-03-30 with total page 1200 pages. Available in PDF, EPUB and Kindle. Book excerpt: Your must-have bench reference for cardiac electrophysiology is now better than ever! This globally recognized gold standard text provides a complete overview of clinical EP, with in-depth, expert information that helps you deliver superior clinical outcomes. In this updated 5th Edition, you’ll find all-new material on devices, techniques, trials, and much more – all designed to help you strengthen your skills in this fast-changing area and stay on the cutting edge of today’s most successful cardiac EP techniques. Expert guidance from world authorities who contribute fresh perspectives on the challenging clinical area of cardiac electrophysiology. New focus on clinical relevance throughout, with reorganized content and 15 new chapters. New coverage of balloons, snares, venoplasty, spinal and neural stimulation, subcutaneous ICDs and leadless pacing, non-CS lead implantation, His bundle pacing, and much more. New sections on cardiac anatomy and physiology and imaging of the heart, a new chapter covering radiography of devices, and thought-provoking new information on the basic science of device implantation. State-of-the-art guidance on pacing for spinal and neural stimulation, computer simulation and modeling, biological pacemakers, perioperative and pre-procedural management of device patients, and much more.

Download or read book Cardiac Arrhythmias written by Wilbert S. Aronow and published by BoD – Books on Demand. This book was released on 2014-02-12 with total page 164 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book is useful for physicians taking care of patients with cardiac arrhythmias and includes six chapters written by experts in their field. Chapter 1 discusses basic mechanisms of cardiac arrhythmias. Chapter 2 discusses the chronobiological aspects of the impact of apnoic episodes on ventricular arrhythmias. Chapter 3 discusses navigation, detection, and tracking during cardiac ablation interventions. Chapter 4 discusses epidemiology and pathophysiology of ventricular arrhythmias in several noncardiac diseases, methods used to assess arrhythmia risk, and their association with long-term outcomes. Chapter 5 discusses the treatment of ventricular arrhythmias including indications for implantation of an AICD for primary and for secondary prevention in patients with and without congestive heart failure. Chapter 6 discusses surgical management of atrial fibrillation.

Download or read book Cardiac Electrophysiology From Cell to Bedside E Book written by Douglas P. Zipes and published by Elsevier Health Sciences. This book was released on 2013-10-11 with total page 1397 pages. Available in PDF, EPUB and Kindle. Book excerpt: Cardiac Electrophysiology: From Cell to Bedside puts the latest knowledge in this subspecialty at your fingertips, giving you a well-rounded, expert grasp of every cardiac electrophysiology issue that affects your patient management. Drs. Zipes, Jalife, and a host of other world leaders in cardiac electrophysiology use a comprehensive, multidisciplinary approach to guide you through all of the most recent cardiac drugs, techniques, and technologies. Consult this title on your favorite e-reader, conduct rapid searches, and adjust font sizes for optimal readability. Compatible with Kindle®, nook®, and other popular devices. Get well-rounded, expert views of every cardiac electrophysiology issue that affects your patient management from preeminent authorities in cardiology, physiology, pharmacology, pediatrics, biophysics, pathology, cardiothoracic surgery, and biomedical engineering from around the world. Visually grasp and easily absorb complex concepts through an attractive full-color design featuring color photos, tables, flow charts, ECGs, and more! Integrate the latest scientific understanding of arrhythmias with the newest clinical applications, to select the right treatment and management options for each patient. Stay current on the latest advancements and developments with sweeping updates and 52 NEW chapters - written by many new authors - on some of the hottest cardiology topics, such as new technologies for the study of the molecular structure of ion channels, molecular genetics, and the development of new imaging, mapping and ablation techniques. Get expert advice from Dr. Douglas P. Zipes - a leading authority in electrophysiology and editor of Braunwald’s Heart Disease and the Heart Rhythm Journal - and Dr. Jose Jalife - a world-renowned leader and researcher in basic and translational cardiac electrophysiology. Access the full text online at Expert Consult, including supplemental text, figures, tables, and video clips.