As the heart muscle contracts and relaxes, the valves open and shut. This lets blood flow into the ventricles and atria at alternate times. Here is a step-by-step description of how the valves work normally in the left ventricle:. When the left ventricle relaxes, the aortic valve closes and the mitral valve opens.
This lets blood flow from the left atrium into the left ventricle. The left atrium contracts. This lets even more blood to flow into the left ventricle. When the left ventricle contracts, the mitral valve closes and the aortic valve opens. This is so blood flows into the aorta and out to the rest of the body.
While the left ventricle is relaxing, the right ventricle also relaxes. This causes the pulmonary valve to close and the tricuspid valve to open. This lets blood flow into the right ventricle that was returned to the right atrium from the body. When the left ventricle contracts, the right ventricle also contracts. This causes the pulmonary valve to open and the tricuspid valve to close. Blood flows out from the right ventricle to the lungs before it is returned to the left atrium as fresh, oxygenated blood.
Regurgitation is a leaky valve. This means the valve doesn't fully close and the blood flows backward through the valve. This results in leakage of blood back into the atria from the ventricles in the case of the mitral and tricuspid valves.
Or it leaks back into the ventricles in the case of the aortic and pulmonary valves. This can cause the chambers to be overworked because they have repump the extra blood that was returned. Each chamber has a one-way valve at its exit that prevents blood from flowing backwards. When each chamber receives an electrical pulse, it contracts, and the valve at its exit opens pumping blood through it and when it is finished contracting the valve closes. As the lower chambers fill with blood, the electrical signal travels along special conduction tissues to the AV node, where it pauses for a few seconds, allowing the chambers to finish filling.
There are four valves in the heart including the Tricuspid Valve , which is at the exit of the Right Atrium, the Pulmonary Valve , which is at the exit of the Right Ventricle, the Mitral Valve , which is at the exit of the Left Atrium and the Aortic Valve , which is at the exit of the Left Ventricle.
When the heart muscle contracts or beats it pumps blood out of the lower chambers of the heart. The heart contracts in two stages. In the first stage the Right and Left Atria contract at the same time, pumping blood to the Right and Left Ventricles. Then the Ventricles contract together called systole to propel blood out of the heart.
After this second stage, the heart muscle relaxes called diastole before the next heartbeat. During this time, the muscle resets itself for contraction and blood fills the atria. The right side of the heart collects oxygen-poor blood from the body and pumps it to the lungs where it picks up oxygen and releases carbon dioxide while the left side collects oxygen rich blood from the lungs and pumps it to the body so that the cells throughout your body have the oxygen they need to function properly.
All blood enters the right side of the heart through two veins, the Superior Vena Cava SVC , which collects blood from the upper half of the body and the Inferior Vena Cava IVC , which collects blood from the lower half of the body. There, the blood picks up oxygen and drops off carbon dioxide in the lungs, and then flows from the lungs through the Pulmonary Veins to the Left Atrium through Mitral Valve to the Left Ventricle through the Aortic Valve to the Aorta through the two main coronary arteries -- the Left Coronary Artery which divides into two - the Left Anterior Descending Artery and the Circumflex Artery and the Right Coronary Artery.
From here blood flows the arterial system to the body. The heart, just like any other organ, requires blood to supply it with oxygen and other nutrients so that it can do its work. The heart does not extract oxygen and other nutrients from the blood flowing inside it. The heart gets its blood from coronary arteries, located on the outside surface of the heart, that eventually carry blood within the heart muscle through a network of branches.
It means that the heartbeat is not sufficient to supply an adequate volume of blood and oxygen to the brain and other parts of the body. When this occurs, a variety of compensatory changes will take place in an effort to pump an adequate amount of blood:.
Over time, these compensatory mechanisms will not be adequate to maintain sufficient circulation. Posted on March 1st, The right atrium receives blood from the veins that has already circulated through the body and pumps it over to the right ventricle.
The right ventricle passes the blood on to the pulmonary artery, which sends it to the lungs to pick up oxygen. The left atrium receives the now oxygen-rich blood from the lungs and pumps it into the left ventricle.
The left ventricle pumps the oxygen-rich blood to the body through a large network of arteries. The contractions of the left ventricle, the strongest of the four chambers, are what create blood pressure in the body. A series of four valves open and close to allow blood to move through the heart. The tricuspid valve that controls blood flow from the right atrium to the right ventricle.
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