Open Access Medical Books



Edited by Richard M. Millis .

340 pages .
Open Access . 

A number of heart diseases in humans are rooted in the structure-function relationships of the lower animal hearts. These relations are observable during human embryonic organogenesis. The hearts of invertebrates and lower vertebrates are similar to the embryonic tubular hearts of higher vertebrates. These primitive ancestral hearts possess cardiac myocytes that are electrically coupled by gap junctions such as those in mammalian and human hearts. The highest pacemaker activity occurs at the receiving end of the primitive ancestral heart, thereby, resulting in waves of peristaltic contractions similar to those in gastrointestinal tracts. This tubular arrangement gives rise to atrial and ventricular chambers with well-developed and well-coupled cardiac myocytes with low pacemaker activity, producing the rapid conduction and contraction of mammalian and human hearts. The forming chambers are made up of rapidly proliferating myocytes with a surrounding area of slowly proliferating trabecular myocardium. This slowly proliferating trabecular myocardium does not differentiate into normal myocardium of the heart chambers because it remains poorly developed. The tightly coupled electrically by highly organized gap junctions and intercalated discs give rise to the ventricular conduction system. Thus, the human ventricular conduction system arises from the embryonic myocardium, and permits rapid conduction of cardiac excitation, and subsequent contraction of the pumping chambers of the heart.
In contrast, to vertebrates, many invertebrates lack an autonomic nervous system for organizing cardiac signaling and insuring responsiveness to a wide variety of complex physiological stimuli. In lower vertebrates, the vagus nerve arises from the brain as a cranial nerve and innervates the pacemaker cells of the heart. When stimulated, the vagus slows the rate at which the cardiac phases of depolarization and repolarization are produced. In higher vertebrates with well- developed heart chambers, specialized for receiving (atria) and pumping (ventricles), the atrial pacemaker cells are innervated by vagal parasympathetic, as well as by sympathetic nerve fibers. This arrangement appears to subserve sophisticated tuning of the heart rate, and pumping activity (contractility) to immediate changes in the physiological state of the animal, insuring adequate flow of nutrients to the various tissue compartments, especially to the complex brains and other vital organs of mammals. In mammals, vagal innervation of pacemaker cells in the sinoatrial node appears to arise from two main sources, the dorsal vagal nucleus in the dorsal brainstem and the nucleus ambiguous in the ventral brainstem. The vagal fibers from the dorsal vagal nucleus appear to be driven mainly by baroreceptor and other cardiovascular inputs. The signaling of these vagal fibers produces variability in the rate of sinoatrial node depolarization associated mainly with changes in blood pressure. The vagal fibers,which arise from the nucleus ambiguous, appear to be driven mainly by respiratory inputs and produces variability in the rate of the sinus node depolarization - known as heart rate variability or respiratory sinus arrhythmia.

The measurement and analysis of heart rate variability has been introduced trough Advances in Electrocardiogram - Methods and Analysis. In the present book, Advances in Electrocardiograms - Clinical Applications, the reader will be presented with clinical applications of heart rate variability, as well as a wide range of pathophysiological conditions associated with abnormal electrocardiograms. From electrolyte disturbances to toxic exposures; from hypertension and myocardial infarction to cardiomyopathies; from sleep apneas to heart failures. Being mindful that the roots of many electrocardiographic abnormalities develop during embryonic organogenesis of the heart, will lead to improved recognition, diagnosis and treatment of cardiac diseases.

Richard M. Millis, PhD
Dept. of Physiology & Biophysics
The Howard University College of Medicine



Part 1 Cardiac Arrhythmias .

 1 The Prognostic Role of ECG in Arterial Hypertension 3 Stavros Dimopoulos, Christos Manetos, Eleni Koroboki, John Terrovitis and Serafim Nanas

 2 Electrocardiographic QT Interval Prolongation in Subjects With and Without Type 2 Diabetes – Risk Factors and Clinical Implications 13 Jimenez-Corona Aida, Jimenez-Corona Maria Eugenia and Gonzalez-Villalpando Clicerio

 3 The Prevalence and Prognostic Value of Rest Premature Ventricular Contractions 27 Matthew D. Solomon and Victor Froelicher

 4 Arrhythmias in Children and Young Adults 41 Harinder R. Singh

 5 Paced ECG Morphology – Reveals More than What It Conceals 77 Ajay Bahl

 6 Electrocardiograms in Acute Pericarditis 83 Anita Radhakrishnan and Jerome E. Granato

 7 The Remodeling of Connexins Localized at Pulmonary Vein – Left Atria in Triggering and Maintenance of Atrial Fibrillation 95 Guo-qiang Zhong, Ri-xin Xiong, Hong-xing Song, Yun Ling, Jing-chang Zhang and Zhe Wei

Part 2 Myocardial Infarction .

 8 ECG in Acute Myocardial Infarction in the Reperfusion Era 113 Massimo Napodano and Catia Paganelli

 9 Mechanisms of Postinfarction Electrophysiological Abnormality: Sympathetic Neural Remodeling, Electrical Remodeling and Gap Junction Remodeling 133 Guoqiang Zhong, Jinyi Li, Honghong Ke, Yan He, Weiyan Xu and Yanmei Zhao

 10 Novel Porcine Models of Myocardial Ischemia/Infarction – Technical Progress, Modified Electrocardiograms Validating, and Future Application 175 Jianxun Liu and Xinzhi Li

Part 3 Autonomic Dysregulation .

 11 The Emergence and Development of Physiological Regulatory Systems of Newborn Infants in a Neonatal Intensive Care Unit 193 Motoki Bonno, Esmot Ara Begum and Hatsumi Yamamoto

 12 Automated Detection and Classification of Sleep Apnea Types Using Electrocardiogram (ECG) and Electroencephalogram (EEG) Features 211 Onur Kocak, Tuncay Bayrak, Aykut Erdamar, Levent Ozparlak, Ziya Telatar and Osman Erogul

 13 Low Heart Rate Variability in Healthy Young Adult Males 231 Richard M. Millis, Stanley P. Carlyle, Mark D. Hatcher and Vernon Bond

 14 The Role of Exercise Test After Percutaneous Coronary Intervention 245 Iveta Mintale, Milana Zabunova, Dace Lurina, Inga Narbute, Sanda Jegere, Ilja Zakke, Vilnis Taluts Dzerve and Andrejs Erglis

Part 4 Cardiotoxicology .

 15 Toxic and Drug-Induced Changes of the Electrocardiogram 271 Catalina Lionte, Cristina Bologa and Laurentiu Sorodoc

 16 Electrocardiogram (ECG) Abnormality Among Residents in Arseniasis-Endemic and Non Endemic Areas of Southwestern Taiwan – A Study of Gene-Gene and Gene-Environment Interactions 297 Ya-Tang Liao, Wan-Fen Li, Chien-Jen Chen, Wei J. Chen, Hsiao-Yen Chen and Shu-Li Wang

 17 Abnormal Electrocardiogram in Patients with Acute Aluminum Phosphide Poisoning 319 Amine Ali Zeggwagh and Maha Louriz

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Published by: younes younes - Tuesday, May 7, 2013


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