3-1. WHAT IS A PULSE?

A pulse is when the left ventricle of the heart contracts. When this happens, blood is suddenly pushed from the ventricle to the main artery (aorta). This sudden forcing of blood from the heart into the arteries causes two things to happen.

a. Artery Expansion. The sudden rush of blood increases the volume of blood in the arteries. In order to accept this increased volume, the arteries expand (stretch). As the arteries quickly contract (go back to normal size), blood is forced from the arteries, through the capillaries, and into the veins.

b. Pulse. In addition to the expansion of the arteries, a "wave" travels through the arteries. This wave is the pulse. All arteries have a pulse, but the pulse is easier to feel (palpate) when the artery is near the surface of the body.