The Hypertrophied Heart

Whenever the heart is challenged with an increased work load for a prolonged period, it responds by increasing its muscle mass--a phenomenon known as cardiac hypertrophy. Although cardiac hypertrophy is commonly seen under physiological conditions such as development and exercise, a wide variety of pathological situa tions such as hypertension (pressure overload), valvular defects (volume overload), myocardial infarction (muscle loss), and cardiomyopathy (muscle disease) are also known to result in cardiac hypertrophy. Various hormones such as catecholamines, thyroid hormones, angiotensin II, endothelin, and growth factors have also been shown to induce cardiac hypertrophy. Although the exact mechanisms underlying or pathological forrns of cardiac hypertrophy are poorly under the physiological stood, an increase in the intraventricular pressure is believed to represent the major stimulus for the development of cardiac hypertrophy. In this regard, stretching of the cardiac muscle has been shown to induce the hypertrophic response, but the role of metabolic influences in this process cannot be ruled out. Furthermore, different hormones and other interventions in the absence of stretch have been observed to stimulate protein synthesis in both isolated cardiomyocyte and vascular myocyte preparations. Nonetheless, it is becoming dear that receptor as well as phospholipid linked signal transduction pathways are activated in some specific manner depend ing upon the initial hypertrophic stimulus, and these then result in an increase in the size and mass of cardiomyocytes.

In the past two decades a number of studies have shown that abnormalities in the function and structure of coronary microcirculation can be detected in several cardiovascular diseases. On the basis of the clinical setting in which it occurs, coronary microvascular dysfunction (CMD) can be classified into four types: CMD in the absence of any other cardiac disease; CMD in myocardial diseases; CMD in obstructive epicardial coronary artery disease; and iatrogenic CMD. In some instances CMD represents an epiphenomenon, whereas in others it represents an important marker of risk or may contribute to the pathogenesis of myocardial ischemia, thus becoming a possible therapeutic target. This book provides an update on coronary physiology and a systematic assessment of microvascular abnormalities in cardiovascular diseases, in the hope that it will assist clinicians in prevention, detection and management of CMD in their everyday activity.

The Social Security Administration (SSA) uses a screening tool called the Listing of Impairments to identify claimants who are so severely impaired that they cannot work at all and thus immediately qualify for benefits. In this report, the IOM makes several recommendations for improving SSA's capacity to determine disability benefits more quickly and efficiently using the Listings.

Diagnosis and Management of Hypertrophic Cardiomyopathy is aunique, multi-authored compendium of information regarding thecomplexities of clinical and genetic diagnosis, natural history,and management of hypertrophic cardiomyopathy (HCM)—the mostcommon and important of the genetic cardiovasculardiseases—as well as related issues impacting the health oftrained athletes. Edited by Dr. Barry J. Maron, a world authority on HCM, and withmajor contributions from all of the international experts in thisfield, this book provides a single comprehensive source ofinformation concerning HCM. Recent advances in the field arediscussed, including the importance of left ventricular outflowtract obstruction, the use of implantable defibrillators for theprevention of sudden death in young people, definition of thegenetic basis for HCM and its role in clinical diagnosis and riskstratification, the development of more precise strategies forassessing the level of risk for sudden death among all patientswith HCM, and the evolution of invasive interventions for heartfailure symptoms, such as surgical management and its alternatives(alcohol septal ablation and dual-chamber pacing). Key Features: Contributions from all experts in the field,representing diverse viewpoints regarding this heterogeneousdisease and related issues in athletes Information to dispel misunderstandings regarding issuesassociated with HCM and cardiovascular disease in athletes The only comprehensive source of information available on thetopic

Heart Hypertrophy and Failure brings together leading basic scientists and clinicians, presenting improved knowledge of the pathophysiology and treatment of the condition. The result is a synthesis of state-of-the-art information on molecular biology, cellular physiology and structure-function relationships in the cardiovascular system in health and disease. The papers presented describe fundamental mechanisms underlying changes in the cellular machinery during the development of cardiac hypertrophy and heart failure. Audience: Students, scientists, clinical and experimental cardiologists who seek to understand and manage the perplexing problems of hypertrophy and heart failure.

This extensively updated edition provides a comprehensive review of hypertrophic cardiomyopathy, the most common genetic disorder of the heart characterized by dysfunctional contractility at the sarcomere level. The disease produces abnormal and oftentimes focal hypertrophy on a macroscopic level that further impairs cardiac performance and may lead to life-threatening arrhythmias. This edition provides a practical approach, establishing evidence-based best practice for all scenarios. Hypertrophic Cardiomyopathy provides readers with key points and critical clinical pearls to assist them in managing patients. New chapters have been included on managing hypertension, sleep apnea, coronary artery disease, structural and congenital disease, nutrition and pharmacotherapies. All aspects of treatment are covered – medications, pacemakers and defibrillators, and invasive septal reduction therapy (both surgical myectomy and alcohol septal ablation) – in addition to genetics, family screening, lifestyle concerns, and athletic screening. The practical approach has been reinforced with an expanded emphasis on creating a Center of Excellence, how to facilitate the multi-disciplinary approach, and on case-based reviews and discussions, with each chapter ending with a post-test. This book is an essential text for cardiology professionals from trainee to board-certified physician, and includes important information for interventional cardiologists, cardiac surgeons, cardiac imagers, critical care physicians, sports medicine physicians, genetic counsellors, and electrophysiologists.