Physiology is generally defined as the study of living organisms and their parts. Heart physiology therefore deals with the heart’s composition and functions. The human heart, which is generally the size of a clenched fist, can be considered the master of the circulatory system. Its main function is to pump blood throughout the body.
The heart has four chambers, or compartments, which work together to create two pumps. This portion of heart physiology can be simplified if the right side of the heart is viewed as the reception center. This is where blood that lacks sufficient oxygen is taken in. That blood is then sent into the lungs, where it receives oxygen. Afterward, the left side of the heart can be viewed as the shipping center, because this is where the blood is sent out.
Atrium is the name given to the upper left and right chambers. Together they are referred to as the atria. Their job is to receive blood into the heart. The lower chambers are called ventricles. Their job is pump blood away from the heart.
This process can be followed by beginning with the superior and inferior vena cava. Although there are veins throughout the body, these are considered major veins. They supply the right atrium with blood, which then passes into the right ventricle. The right ventricle empties its blood into the pulmonary artery, which is a sort of passageway to the lungs.
After being oxygenated, the blood flows from the lungs to the other reception chamber, the left atrium. Then, the blood passes into the left ventricle where it is ejected to a trunk called the aorta. This trunk then distributes the blood to the entire body, except the lungs, via a network of arteries.
A natural valve system that prevents backflow is another interesting part of heart physiology. The tricuspid valve prevents blood from flowing from the right ventricle back into the right atrium. The mitral valve is the one responsible for keeping blood that has entered the left ventricle from returning to the left atrium.
The heart is a muscle with a network of nerves that are designed to allow constant, coordinated contraction and relaxation. First, the two atria simultaneously contract. This contraction is what forces the blood into the ventricles. Then, the heart relaxes, allowing the atria to receive more blood.
Shortly after the atria contract, the ventricles contract. This contraction pushes blood out of the heart. After the blood is released, two valves called the aortic and the pulmonary close, preventing blood from returning into the ventricles. Meanwhile, the ventricles begin to refill with blood from the atria.
Outlining heart physiology can be a bit misleading. Describing how the heart functions makes it sound as though a series of timely stop and go actions take place. In reality, the functions of the heart are quick and constant, with many actions occurring simultaneously.