Video: Left ventricle

Hey, everyone! It’s Matt from Kenhub, and in this tutorial, we will discuss the left ventricle. The cardiac ventricles are the two lower chambers of the heart quadrants. They are larger than the atria but narrow as they approach the apex. They function by collecting the blood that flows into them from the atria and then contract in order to expel the accumulated blood volume into the peripheral tissues using the major vessels to carry it to the extremities.

The left ventricle as you can now see highlighted in green from the diaphragmatic surface of the heart receives blood from the left atrium of the heart via the relaxation of the mitral valve. When it contracts, it pushes the blood volume through the aortic valve and into the aorta. In comparison to the right ventricle, the left one is both shorter in length and is transversely circular in a concave manner. It forms the lesser part of the sternocostal surface of the heart anterosuperiorly, the larger part of the diaphragmatic surface inferiorly as well as the apex of the heart.

The left ventricle is 3 to 6 times thicker than the right. The reason for the increased thickness of the left ventricular wall is that it has to be able to withstand the 5 times stronger contraction forces and blood pressure needed to propel the blood around the entire body without having it stall or collect anywhere.

The left ventricle collects oxygenated blood returning from the lungs at approximately 80 mm/Hg and expels it into the aorta at around 120 mm/Hg during every heartbeat. The typical blood volume that can be pumped out of the heart per minute at rest which is also known as the cardiac output is about 5 liters/minute and this numerical evaluation can increase to between 25 and even 45 liters/minute in athletes during exercise.