The Left Ventricle of the Heart

Both the right and left atrium contract causing blood to flow though the two valves, and then into the left ventricle. The left ventricle pumps blood into the systemic circulation through the aorta. This systemic circulation system is much bigger than the pulmonary circulation system, which is why the left ventricle is so big. The blood on the left side of the heart is oxygenated. It becomes oxygenated when the deoxygenated blood passes through the right atrium and then flows into the left ventricle. It is then pumped along the pulmonary artery into the lungs where it is oxygenated. It then travels through the pulmonary veins back into the heart. It enters through the left atrium and then travels to the left ventricle. This process is repeated over and over again, to make blood continuously flow through the heart, lungs and body. This process ensures that there is always enough oxygen for the body to work

When the left atrium is filled with blood, the heart contracts and the blood passes through the bicuspid valve and into the left ventricle.

The heart’s moves oxygen-rich blood from the lungs to the left atrium onto the left ventricle which then pumps it to the rest of the body. The left ventricle generates the heart’s pumping power therefore it is larger than the other chambers. In left-sided heart failure, the left side of the heart works harder to pump the same amount of blood that is normally pumped. There are two types of left-sided heart failure- the systolic and the diastolic. In systolic failure, the left ventricle is not able to normally contract and the heart cannot push enough blood into the circulation. In systolic failure, the left ventricle is not able to relax because the muscle has become stiff. As a result, the heart cannot properly fill with blood during resting period between each beat. Right-sided heart failure is another type of heart failure that results from the failure of the left-side. The heart’s pumping action moves blood that returns to the heart though the veins through the right atrium and then onto the right ventricle which pumps the blood back out of the heart into the lungs to be replenished with oxygen. When the left ventricle

The cardiovascular system uses blood to transport oxygen, nutrients, and other materials throughout the body. The heart is made of cardiac muscle and is composed of 4 distinct chambers. The right side of your heart collects blood on its return from the rest of our body. The blood entering the right side of your heart is low in oxygen. Your heart pumps the blood from the right side of your heart to your lungs so it can receive more oxygen. Once it has received oxygen, the blood returns directly to the left side of your heart, which then pumps it out again to all parts of your body through arteries (the aorta).

Its function is to close off the lower left chamber that holds oxygenated blood before it is pumped out to the body through the aorta. Another function of the aortic valve is to open to allow blood to leave the heart. These semilunar valves are controlled by changes in pressure. They open when the ventricles are releasing blood into the arteries and close when the pumping action is complete. The right AV valve also known as the tricuspid valve because of the three cusps that extend into the ventricular chamber. It is located between the right atrium and right ventricle and its function is to close off the right atrium that holds blood coming in from the body and opens to allow blood to flow from the top right atrium to the right ventricle. The left AV valve also referred to as the bicuspid or mitral valve is located between the left atrium and left ventricle. The function of this valve is to close off the left atrium

The heart’s function is to move oxygenated blood from the lungs to the left atrium, then on to the left ventricle, pumps it to the rest of the body. The left ventricle supplies most of the heart 's pumping power; therefore, the left ventricle is larger than the other chambers and essential for normal function. In left-sided or left ventricular (LV) heart failure, the left side of the heart must work harder to pump the same amount of blood (American Heart Association -AHA, 2016).

The heart is divided into four chambers. The top two chambers are the atria and the bottom two chambers are the ventricles. Two of the chambers, together make up the right heart and pump blood to your lungs, where it picks up oxygen. Blood that is carrying oxygen then travels to the two chambers on the left side of your heart, which then pumps the blood to the rest of your body. The ventricles (the bottom chambers) are powerful pumping chambers, which push the blood out of the heart when they contract. The smaller and less powerful top chambers of the heart (the atria), help to fill the ventricles with blood for the next contraction. The regulation and coordinated pumping action of the heart is provided by a network of electrical connections, which deliver electrical signals to the heart

The heart is able to do this thanks to the specialized cardiac muscle it contains. The contraction of the heart displays excitatory- contraction coupling (EC coupling) similar to skeletal muscles except the action potential in the heart originates spontaneously at the peace maker of the heart (Silverthorn, 2013). Contraction happens when a rapid depolarization occurs due to the influx and opening of sodium voltage gated channels to raise the membrane potential toward the threshold value causing a firing of action potential. The conduction and cardiac cycle starts at a resting distol state for both ventricles and atriums and is initiated with the depolarization at the SA node (Silverthorn, 2013). This causes an action potential which moves rapidly towards the AV node where the signal gets slowed down (Silverthorn, 2013).When the signal reaches this point it causes a contraction/systole stage of the right and left atriums. This causes blood to be pumped into the ventricles through the AV valves (Silverthorn, 2013). The action potential then travels to the ventricles down the bundle branches out towards the Purkinje fibers (Silverthorn, 2013). In terms of the cardiac cycle an isovolumetric contraction occurs during the pause of the signal at the AV node allowing the AV valves to close, followed by ventricular systole where the ventricles expel blood into circulation (Silverthorn, 2013). The final stage in the cardiac cycle occurs between stimulations of action potential when the ventricles and atriums are in diastole and the chambers fill with blood once again (Silverthorn,

In the systemic circuit blood returns from the lungs into the left atrium. Once in the left atrium blood flows though the left atrioventricular valve into the left ventricle. The left ventricle then contracts and the aortic valve opens because of the contraction. Blood then flows through he aortic valve into the ascending aorta and then once in the aorta it is then sent to every organ in the body where it excretes oxygen and intakes carbon dioxide. Finally, the carbon dioxide rich blood returns itself to the heart for the process to reoccur again. Both circuits must always maintain circulation so that blood can be constantly disbursed throughout the body (The Heart, Slide 11

The heart is divided into four chambers; the superior chambers (atria) receive blood and are connected to the inferior chambers (ventricle), through the atrioventricular valves. Once in the ventricles, blood is ejected to the vasculature through the semilunar valves. These valves, similar to the ones in the veins, ensure the unidirectionality of blood flow.

stimulates the atrium to contract forcing blood through the valves to the ventricles. The AV

The left chamber, lower at the heart, takes in oxygenated blood through the mitral valve from the left atrium while it contracts. The aortic valve leading to the aorta is closed while this occurs. At the same time, the aortic valve leading to the aorta is closed giving the ventricle the opportunity to fill with blood. The ventricles contract as both ventricles are full. When the left ventricles contract, the aortic valve opens as the mitral valve closes. When the mitral valve closes it prevents blood from coming back into the left atrium and the opening of the aortic valve giving way for the blood to flow into the aorta. From there it goes throughout the body. The left and right ventricles also contract together, but when the left ventricle

The inside of the heart is separated into four chambers, the left and right atria and the left and right ventricles. The ventricles hold responsibility for pumping blood around the body and they are the thickest muscle of the heart. The two atria form the curved top of the heart and the ventricles join at the bottom of the heart to create a pointed base which is directed towards the left side of the chest. The left ventricle contracts most forcefully, in order for the heart beat to be felt most strongly on the left side of the chest. A wall, known as the septum, divides the right and left sides of the heart and a valve connects each atrium to the ventricle below it. The mitral or bicuspid valve connects the left atrium with the left ventricle. The tricuspid valve connects the right atrium with the right ventricle.

In a sweeping fashion, the right atrium contracts and forces the final volume of blood into the right ventricle. The left atrium contracts and contributes the final 20% of volume to the left ventricle.

When blood enters through the inferior and superior vena cava, into the right atrium, from the pulmonary veins into the left atrium. The right atrium contracts slightly before the left because it is first to receive the signal. During this contraction, diastole is occurring, the ventricles expand, and their pressure drops below the atria, which causes the AV valves to open and blood flows into the ventricles, causing pressure to rise and atrial pressure to fall.