Understanding Cardiology (from Greek: καρδιά (cardia) which means the heart) is the branch of medicine devoted to learning the heart and blood vessel disease. Anatomy and Physiology The heart is the most vital organs, because the heart is part of the blood peeredaran system. Peredarah our blood system consists of the heart, blood vessels and lymph vessels that play a role in the pump or circulate blood throughout the body. The heart is a vital organ that acts as the central circulation. If an interruption occurs just a little on the heart will cause disruption of the body as a whole. And if the heart stops working, then that's when the end of human life occurred. Anatomy Based on the study of anatomy, the structure of the human heart can be described as follows: 1. Heart valve Adah heart valves or lining membrane that play a role in the regulation of blood flow in heart valves. Working heart valves are automatic, ie the valve will only open in a certain direction (the direction of blood flow) and closed in the other direction. Heart valve berjummlah four sheets. Two of them known as the atrioventricular valves (antrioventricular valve). Both valves are located between the indoor atrium and ventricle of the heart. Meanwhile, two other valves known as the semilunar valves (semilunar valve). These valves are between the ventricles and arteries (blood vessels carrying blood to the heart). Semilunar valve is located between the ventricles kana kana and pulmonary artery (the artery that connects to the lungs) called the pulmonary valve (pulmonary valve), while the left semilunar valve is located between the left ventricle and the aorta (main artery) is called the aortic valve (aortic valve) . 2. Myocardium (heart muscle) Myocardium or heart muscle is the muscle tissue surrounding the heart and form the heart wall. Heart wall is formed by the myocardium has a different thickness on each part. The walls of the atrium space to accommodate functions from outside the heart blood thinner walls than the ventricles that serves to pump blood out of heart. 3. Pericardium The pericardium is a sac that the heart has two layers. The first layer on the inside of the pericardium is called epicardium. This layer is part of the pericardium in direct contact with the heart muscle. Meanwhile, the outer layer of the pericardium is the layer in direct contact with the breastbone and other structures inside the chest cavity. This layer serves to maintain the heart remains in place. 4. Endocardium Endocardium is a thin membrane in the form of shiny white tissue that protects the inside of the heart cavity. Endocardium was also instrumental help blood flow smoothly and prevents attachment of blood on the walls of the heart. 5. Coronary arteries (coronary artery) Coronary arteries are blood vessels that play a role arteries supplying blood to the heart muscle. Physiology In the circulatory system, the heart not only served to pump blood throughout the body, but more than that, the heart can also mmemberikan response to changing oxygen levels in the blood. Human circulatory system that involves the activity of the heart is a double circulatory system. Ha this is because the blood through the heart as much as 2 times. The blood circulation is divided into two, a small circulation and a large circulation. 1. Small circulation is peeredaran blood from the heart to the lungs and back to janutng. 2. Peredarah large blood is the blood circulation from the heart throughout the body and back again to the heart. Circulatory mechanisms are in fact can be explained as follows: 1. Blood is pumped from the heart to the lungs contains a lot of carbon dioxide. In the lung (alveoli) in exchange (diffusion) between the carbon dioxide with oxygen. Oxygenated blood is then channeled back to the heart and then flows through the body. 2. The blood that contains oxygen is pumped by the heart throughout the body. Oxygen in the blood is used for the respiration of body cells that produce carbon dioxide, which will then be channeled back to the heart and lungs to be excreted through the respiratory process.