ABOUT THE HEART
Anatomy
The heart is located between the lungs in the middle of your chest, behind and slightly to the left of the breastbone (sternum).
The heart has 4 chambers. The upper chambers are called the left and right atria, and the lower chambers are called the left and right ventricles. A wall of muscle called the septum separates the left and right atria and the left and right ventricles.
The heart’s job is to supply the body with oxygen-rich blood. First it sends blood without any oxygen to the lungs to get oxygen. It then returns it to the heart where the blood containing oxygen will be pumped to the rest of the body.
Blood Flow Through the Heart
On the Right Side:
Oxygen poor blood (blue) is pumped into the right upper chamber (right atrium) of the heart, where it is then pumped into the right lower chamber (right ventricle) and taken to the lungs to be oxygenated.
On the Left Side:
Oxygen-rich blood (red) then travels back from your lungs into the left upper chamber (left atrium). It is then pumped into the left lower chamber (left ventricle) where it is pumped out to travel around the body.