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Anatomy of the Heart: Blood flow through the Heart and the Heart Valves involved.
Structures of the Hearts Anatomy
The anatomy of the heart begins with the size, which is about the size of a fist. The heart is made of muscle and is located in the center of your chest right between the lungs. The area it is located is known as the mediastinum. Each time your heart beats it pumps about 5 L a minute. During exercise your heart can double that amount. The heart has protective covering called the pericardium. The heart has a muscular wall known as the septum, which separates the heart into two halves right and left. There are two upper chamber of the heart known as the atrium, and the lower two chambers of the heart knows the ventricles.
Anatomy of the heart: right atrium
The right atrium receives the blood from your body through the vena cava, from the upper (superior) and lower (inferior) portions of your body. The blood that comes through the vena cava has no oxygen, because the blood drops the oxygen off to places such as your brain, lungs, kidneys and other vital organs in your body. Without oxygen these organs would fail. The right atrium also receives blood from the heart muscle by way of the coronary sinus, which helps provide the much needed oxygen to the heart muscle. Most of the blood flows freely through the right atrium, through the open tricuspid valve and down into the right ventricle. The filling of the right ventricle is known as ventricular diastole. The remaining blood is then pushed from the right atrium into the right ventricle during atrial systole also known as the contraction. Atrial systole is the only time blood is actively pushed into the right ventricle. The rest of the time, which consists of mere milliseconds, the blood flows passively through the right atrium into the right ventricle. Learn exactly how the heart works!
Anatomy of the Heart
Anatomy of the Heart
Anatomy of the heart : Right ventricle, and left atrium
The right ventricle is located right behind your sternum and is a muscular pump. This is why during CPR, one of your landmarks is the sternum. During CPR the sternum is used during compressions to help pump blood from the right ventricle. The right ventricle builds up enough pressure to close the tricuspid valve and open the Monica valve and send the blood shooting into the pulmonary artery which leads to the lungs. The purpose of this is for the blood to go pick up more oxygen from the lungs. Once the blood gets more oxygen from the lungs, it flows freely from the four pulmonary veins into the left atrium and down into the left ventricle, this is also known as ventricular diastole. So, keep in mind the blood has just picked up fresh oxygen from the lungs and is ready to be injected from the left ventricle back into your body system.
Anatomy of the heart: left ventricle
Once your blood reaches the left ventricle is filled with oxygen. Once the left ventricle is nearly full the left atrium then contracts and pumps the remaining blood into the left ventricle. Now the left ventricle is full this is the beginning of a systolic contraction. The pressure in the systolic contraction is enough to close the mitral valve. Remember the mitral valve is allowing blood to go into the left ventricle from the left atrium. After the mitral valve closes the pressure from the left ventricle opens the aortic valve. The blood is then injected into the aorta and into the bodies arterial (oxygen) circulation system. The main purpose of this, is to provide fresh oxygen to the body's organs. This includes your skin because your skin is your largest organ.
Pictue of Human Heart
Four Valves in Heart
Anatomy of the heart: mitral and tricuspid valves
There are four cardiac valves that are in charge of moving blood through the different chambers of the heart. The valves respond to pressure the helps them to open and close in between the heart's chambers. The mitral valve connects the right atrium into the right ventricle. The tricuspid valve connects the left atrium to the left ventricle. The valves are broken into two types. You have the atrioventricular valves in the semilunar (crescent shaped) valves. As the name implies the atrioventricular valves separate the atria from the ventricles, these valves are your mitral and tricuspid valves. During ventricular diastole these valves are opened up like funnels so blood can flow down through them from the atria to the ventricles. During systole, the valves close up to prevent the blood from going back into the atria. This is known as regurgitation.
Anatomy of the heart: aortic and pulmonic valve
The semilunar valves, meaning crescent shaped, include the aortic and pulmonic valve. These valves prevent blood from going back into the ventricles. The pulmonic valve separates the right ventricle from the pulmonary artery. Remember, the right ventricle sends blood that is oxygen-poor back to the lungs for more oxygen. The aortic valve separates the left that school from the aorta. Remember, the aorta carries the oxygen rich blood back into the body system whether it be for organ tissue, muscles, or skin.
Anatomy of the heart: coronary arteries
The heart receives the blood that it needs from the coronary artery system. The coronary arteries begin to branch out from the aorta, just past the aortic valve. The left coronary artery is in charge of feeding oxygen to the left side of the heart in the right coronary artery is in charge of feeding oxygen to the right part and the lower wall of the left side of the heart. The flow of blood through the coronary artery system happens mainly during diastole. This is where mean arterial pressure comes into play. Mean arterial pressure basically means the blood flow needed to provide oxygen to the major body organs such as kidneys and brain. The normal value for mean arterial pressure is between 70 and 110. The mathematical equation for mean arterial pressure is MAP = [(2 x diastolic)+systolic] / 3. The left main coronary artery divides into two branches the left anterior descending the left circumflex coronary artery. The left anterior descending artery provides blood flow to parts of the left ventricle, the ventricular septum, chordae tendineae, papillary muscle, and a little bit of the right ventricle. The left circumflex coronary artery goes down to the lateral wall of the left ventricle and the apex of the heart it provides blood to the left atrium, the lateral and posterior surfaces of the left ventricle, and also some portions of the inner ventricular septum. For some reason, about half of people have their sinoatrial node supplied by the left circumflex coronary artery. In the very minute portion of people coronary artery supplies AV node. The right coronary artery starts from the right sinus of the Valsalva goes around the heart and down into the apex of the right ventricle. The right coronary artery is especially important because it supplies blood flow with oxygen to the right atria) triple a and the lower portions of the left ventricle. However in some people the right coronary artery supplies the SA node and everyone else right coronary artery supplies AV node. I will publish another article on AV nodes specifically to go over these check back often for new updates.