What do you call the pressure of the blood coming out from the heart?

The heart has two pumps inside of it and each has two chambers and two valves. The left side of the heart has the biggest chambers, and the one that pumps the blood to your body is called the left ventricle, When it contracts (squeezes together), the first valve closes shut (that's the "lupp" sound of a heart beat) and the contraction pushes the blood up past the second valve and into aorta, which is the main artery that distributes the blood to the regular arteries that carry the blood throughout the body. When the blood goes into the aorta, the second valve shuts so the blood doesn't go backwards into the heart and that is the "dubb" sound of a heart beat.