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Structure & Function of the Heart: Risk factors for Coronary Artery disease: Coronary Artery Disease:
Emergency Complications of Heart Attack:
Coronary Artery Bypass Grafting (CABG):
Rheumatic Fever and Heart Valve Diseases:
Heart Transplantation and Assisted devices
Important Heart Questions and Answers
Common Drugs Used For Treatment of Heart Diseases Have your Child been diagnosed with a Congenital Heart Disease??
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Normal Heart and blood Circulation "The Cardiac Cycle" The heart is located at the center of the chest cavity and whose job it is to supply your body organs and tissues with blood. The heart starts its first beat during the 18 weeks of pregnancy and it is perhaps the most powerful and hardworking muscle of your body — it is expected to perform continuously without missing a single beat for your entire life. Think of your heart as a very efficient pump (If this pump is weakened, you can develop several heart disease symptoms such as shortness of breath). It helps convert the food you eat into mechanical energy, which is then used to pump blood first through the lungs, where it becomes oxygenated, and then throughout the rest of the body. Your heart is about the size of your fist and rests slightly to the left of center under your breastbone or sternum. It has four chambers: the two upper chambers are blood reservoirs, called atria, and the two lower chambers are powerful pumping chambers called ventricles. The right and left ventricles are separated by a common wall called the interventricular septum, and the atria are separated by the interatrial septum. These common walls, like the rest of the heart, are composed of heart muscle called myocardium and they can be deficient in some congenital heart diseases (septal defects which can lead to several heart disease symptoms such as palpitations ).
Blood begins its journey toward the heart in millions of tiny blood vessels called capillaries throughout the body. Capillaries are the smallest elements of the circulatory system and are where the transfer of oxygen and nutrients from blood to the body’s tissues occurs. After the blood gives off the oxygen in the capillaries, it turns a dark red to purple color. The red blood cells in the capillary then pick up the carbon dioxide molecules that are the byproducts of cell and tissue function. Capillaries feed into small veins, which in turn feed into larger veins as blood moves closer to the heart. The veins from the abdomen and lower body drain into the inferior vena cava. This large vein is about the same diameter as your thumb and drains directly into the right atrium. The blood returning from almost the upper half of the body drains into the superior vena cava, which in turn drains into the right atrium. When the unoxygenated blood reaches the right atrium, it flows through the tricuspid valve (narrowing of this valve can lead to several heart disease symptoms such as edema) into the right ventricle. Like the other three heart valves, the tricuspid valve is a one-way valve and does not allow blood to flow backwards. After the right ventricle fills with blood, it begins to contract, pumping blood out through the pulmonary valve and to the pulmonary artery. The pulmonary artery carries unoxygenated blood into the lungs. In the lungs, carbon dioxide molecules are given off by the red blood cells. These tiny molecules travel through the capillary wall into small air sacs called alveoli. In turn, the oxygen that we breathe in moves through the alveoli wall and is taken up by the blood. The newly oxygenated blood next passes into the pulmonary veins, which carry the oxygenated blood back to the heart. This oxygenated blood is bright red. Blood returning through the pulmonary veins empties into the left atrium. Once in the left atrium, blood flows through another one-way valve called the mitral valve (narrowing of this valve can lead to several heart disease symptoms such as shortness of breath) into the left ventricle. The left ventricle is the heart’s main pumping chamber. As the left ventricle contracts, the mitral valve closes and the aortic valve opens (narrowing of this valve can lead to several heart disease symptoms such as syncope or fainting). Blood is forced through the one-way aortic valve into the aorta, which is the main artery of the body and somewhat larger than your thumb. The aorta is divided into 3 parts. The ascending aorta which is the first part and goes up towards the neck. The second part of the aorta is called the aortic arch which makes a curve in the top of the chest and gives main arterial branches to the head and neck and upper limbs before changing its route and becoming the third part which is the descending aorta. The descending aorta runs down through the chest and into the abdomen toward the pelvis. It divides into two arteries, known as iliac arteries, which supply the pelvis and legs with oxygenated blood. In the abdomen, the aorta gives off numerous branches to supply blood to different organs, muscles, and tissues like your kidneys, liver and intestines. Blood is the fluid of life that both nourishes and cleans your body. It is the means by which oxygen, tiny food particles, and other nutrients are delivered to tissues and, on the other hand, waste products are removed and eventually discarded by the lungs, liver, and kidneys. The blood consists of plasma, which is a yellow in color, and three types of cells suspended in the plasma: red blood cells, white blood cells, and platelets (those which start a blood clot formation and initiate a heart attack) . Blood travels through a network of arteries and veins. Arteries typically carry bright red, oxygenated blood from the heart to the tissues, whereas veins carry dark purple, unoxygenated blood back to the heart. The tiniest blood vessels linking the two kinds of vessels are called capillaries. Capillaries are so small that blood cells travel through some capillaries in single file. The diameter of a capillary can be very very small and usually require a microscope to magnify and see them. Plasma is mostly water but contains hundreds of other substances, including proteins, digested food, waste products, and electrolytes, which are mainly minerals in solution. There are substances in blood that cause clotting in response to injury. There are also dissolved gases and chemical transmitters called hormones. Hormones, which originate in various glands, activate or deactivate certain bodily functions. Serum is a term often confused with plasma. Serum is plasma that has had the clotting elements removed. Each of the three formed elements in blood has a specific function. Red blood cells are produced in the bone marrow and are also called erythrocytes. One milliliter of blood contains millions of red blood cells. Their main job is to carry oxygen from the lungs to the body and to carry carbon dioxide from the tissues to the lungs. white blood cells are reponsible for your immunity and defending your body against microbes and infectios. Platelets, together with clotting factors, are responsible for stopping bleeding when a blood vessel gets injured.
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Heart disease Symptoms and signs:
NonInvasive diagnostic tests For heart disease:
Invasive Diagnostic Tests for heart disease: Cardiac Arrythmias and Pacemakers:
Aortic Aneurysms
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