Heart Failure - In- Depth Report. In- Depth From A. D. A. M. Background. To understand what occurs in heart failure, it helps to be familiar with the anatomy of the heart and how it works. The heart is composed of two independent pumping systems, one on the right side, and the other on the left. Each has two chambers, an atrium and a ventricle. PRS10 Rubidium Oscillator. The PRS10 is an ultra-low phase noise, 10 MHz rubidium-disciplined crystal oscillator. The device fulfills a variety of communication. MSN Health and Fitness has fitness, nutrition and medical information for men and women that will help you get active, eat right and improve your overall wellbeing. A B C D E F G H I K L M N O P R S T U V W X Z. Aerated Autoclaved Concrete (AAC) Precast concrete that is cured by steam pressure inside a kiln called autoclave. The ventricles are the major pumps in the heart. The external structures of the heart include the ventricles, atria, arteries, and veins. Arteries carry blood away from the heart while veins carry blood into the heart. The vessels colored blue indicate the transport of blood with relatively low content of oxygen and high content of carbon dioxide. Data loss prevention (DLP) is a strategy for making sure that end users do not send sensitive or critical information outside of the corporate network.Figure 1 Relationships between Changes in Food and Beverage Consumption and Weight Changes Every 4 Years, According to Study Cohort. Study participants included. The MAUDE database houses medical device reports submitted to the FDA by mandatory reporters 1 (manufacturers, importers and device user facilities) and voluntary. Most steroid users are not athletes. Between 1 million and 3 million people (1% of the population) are thought to have misused AAS in the United States. TEXAS MODEL NUMBER CONFIGURATOR & OPTIONS Voltage Code for Electrical System Surge Current Rating Options TE ll XAS ll ll l. Common North American Systems. The vessels colored red indicate the transport of blood with relatively high content of oxygen and low content of carbon dioxide. The Right Side of the Heart. The right system receives blood from the veins of the whole body. Its function is to pump the blood into the lungs. The lungs restore oxygen to the blood and exchange it with carbon dioxide, which is exhaled. The Left Side of the Heart. The left system receives blood from the lungs. This blood is now rich in oxygen. The oxygen- rich blood returns through veins coming from the lungs (pulmonary veins) to the heart. The heart receives the oxygen- rich blood from the lungs in the left atrium, the first chamber on the left side. Here, it moves to the left ventricle, a powerful muscular chamber that pumps the blood back out to the body. The left ventricle is the strongest of the heart's pumps. Its thicker muscles need to perform contractions powerful enough to force the blood to all parts of the body. This strong contraction produces systolic blood pressure (the first and higher number in blood pressure measurement). The lower number (diastolic blood pressure) is measured when the left ventricle relaxes to refill with blood between beats. Blood leaves the heart through the aorta, the major artery that feeds blood to the entire body. The Valves. Valves are muscular flaps that open and close so blood will flow in the right direction. There are four valves in the heart: The tricuspid regulates blood flow between the right atrium and the right ventricle. The pulmonary valve opens to allow blood to flow from the right ventricle to the lungs. The mitral valve regulates blood flow between the left atrium and the left ventricle. The aortic valve allows blood to flow from the left ventricle to the aorta. The Heart's Electrical System. The heartbeats are triggered and regulated by the conducting system, a network of specialized muscle cells that form an independent electrical system in the heart muscles. These cells are connected by channels that pass chemically- triggered electrical impulses. Description of Heart Failure. Heart failure is not a disease. It is a condition or process in which the heart is unable to pump enough blood to meet the needs of the body's tissues. Rather, it weakens, usually over the course of months or years, so that it is unable to pump out all the blood that enters its chambers. As a result, fluids tend to build up in the lungs and tissues, causing congestion. This condition used to be called . Heart failure can occur in several ways: The muscles of the heart pumps (ventricles) become thin and weakened. They stretch (dilate) and cannot pump the blood with enough force to reach all the body's tissues. The heart muscles stiffen or thicken. Here, they lose elasticity and cannot relax. Insufficient blood enters the chamber, so not enough blood is pumped out into the body to serve its needs. Sometimes the valves of the heart are abnormal. They may narrow, such as in aortic stenosis, causing a back up of blood, or they may close improperly so that blood leaks back into the heart. The mitral valve (which regulates blood flow between the two chambers on the left side of the heart) often becomes leaky in severe heart failure - - a condition called mitral regurgitation. The very mechanisms that the body uses to compensate for inefficient heart pumping can, over time, change the architecture of the heart (called remodeling) and finally lead to irreversible problems. The specific effects of heart failure on the body depend on whether it occurs on the left or right sides of the heart. Over time, however, in either form of heart failure, the organs in the body do not receive enough oxygen and nutrients, and the body's wastes are removed slowly. Eventually, vital systems break down. Failure on the Left Side (Left- Ventricular Heart Failure). Failure on the left side of the heart is more common than failure on the right side. The failure can be a result of abnormal systolic (contraction) or diastolic (relaxation) action: Systolic. Systolic heart failure is a pumping problem. In systolic failure, the heart muscles weaken and cannot pump enough blood throughout the body. The left ventricle is usually stretched (dilated). Fluid backs up and accumulates in the lungs (pulmonary edema). Systolic heart failure typically occurs in men between the ages of 5. Diastolic. Diastolic heart failure is a filling problem. When the left ventricle muscle becomes stiff and cannot relax properly between heartbeats, the heart cannot fill fully with blood. When this happens, fluid entering the heart backs up. This causes the veins in the body and tissues surrounding the heart to swell and become congested. Patients with diastolic failure are typically women, overweight, and elderly, and have high blood pressure and diabetes. Failure on the Right Side (Right- Ventricular Heart Failure). Failure on the right side of the heart is most often a result of failure on the left. Because the right ventricle receives blood from the veins, failure here causes the blood to back up. As a result, the veins in the body and tissues surrounding the heart to swell. This causes swelling in the feet, ankles, legs, and abdomen. Pulmonary hypertension (increase in pressure in the lung's pulmonary artery) and lung disease may also cause right- sided heart failure. Ejection Fraction. To help determine the severity of left- sided heart failure, doctors use an ejection fraction (EF) calculation, also called a left- ventricular ejection fraction (LVEF). This is the percentage of the blood pumped out from the left ventricle during each heartbeat. An ejection fraction of 5. Patients with left- ventricular heart failure are classified as either having a preserved ejection fraction (greater than 5. Patients with preserved LVEF heart failure are more likely to be female and older, and have a history of high blood pressure and atrial fibrillation (a disturbance in heart rhythm). In- Depth From A. D. A. M. Causes. Heart failure has many causes and can evolve in different ways. It can be a direct, last- stage result of heart damage from one or more of several heart or circulation diseases. It can occur over time as the heart tries to compensate for abnormalities caused by these conditions, a condition called remodeling. In all cases, the weaker pumping action of the heart means that less blood is sent to the kidneys. The kidneys respond by retaining water and salt. This in turn increases edema (fluid buildup) in the body, which causes widespread damage. High Blood Pressure. Uncontrolled high blood pressure (hypertension) is a major cause of heart failure even in the absence of a heart attack. In fact, about 7. It generally develops as follows: The heart muscles thicken to make up for increased blood pressure. The force of the heart muscle contractions weaken over time, and the muscles have difficulty relaxing. This prevents the normal filling of the heart with blood. Hypertension is a disorder characterized by consistently high blood pressure. Generally, high blood pressure consists of systolic blood pressure (the . It is the most common cause of heart attack and involves the build- up of unhealthy cholesterol in the arteries, with inflammation and injury in the cells of the blood vessels. The arteries narrow and become brittle. Heart failure in such cases most often results from a pumping defect in the left side of the heart. People now often survive heart attacks, but eventually many develop heart failure from the physical damage the attack does to the heart muscles. Ironically, heart attack recovery is probably one of the major factors in the dramatic increase in heart failure cases over the past decade. Valvular Heart Disease. The valves of the heart control the flow of blood leaving and entering the heart. Abnormalities can cause blood to back up or leak back into the heart. In the past, rheumatic fever, which scars the heart valves and prevents them from closing, was a major cause of death from heart failure. Fortunately, antibiotics have relegated this disease to a minor cause of heart failure. Birth defects may also cause abnormal valvular development. Although more children born with heart defects are now living to adulthood, they still face a higher than average risk for heart failure as they age. Cardiomyopathy. Cardiomyopathy is disease that damages the heart muscles and leads to heart failure. There are several different types. Injury to the heart muscles may cause the heart muscles to thin out (dilate) or become too thick (become hypertrophic). In either case, the heart doesn't pump correctly. Viral myocarditis is a rare viral infection that involves the heart muscle and can produce either temporary or permanent heart muscle damage. Dilated Cardiomyopathy. Dilated cardiomyopathy involves an enlarged heart ventricle. The muscles thin out, reducing the pumping action, usually on the left side. Although this condition is associated with genetic factors, the direct cause often is not known. Researchers think that an autoimmune response occurs in which infection- fighting antibodies attack a person's own proteins in the heart, mistaking them for foreign substances. Chronic alcohol abuse can damage the heart muscles, can cause hypertension, and may be one cause of idiopathic dilated cardiomyopathy.
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