The Cardiovascular System - Your Heart

By: Alere Staff

The heart is a unique type of muscle in our bodies. It is the “pump” which beats 70 to 80 times per minute, sending oxygen-rich blood to all of our vital organs.2 Over a lifetime, our hearts beat over 2.5 billion times without ever stopping to rest.1

Our heart muscle is in the shape of a pear, which is approximately the size of a clenched adult fist.3 Your heart is located in the middle of the chest behind the breast bone and in between the lungs.1 

The heart muscle, made of cardiac muscle, surrounds four chambers, open spaces inside which collect blood. The chambers are separated by valves or “gates”.3

Each time the heart beats, blood moves through each of the four chambers. There are two chambers on the right side of the heart which pump blood to our lungs where it picks up oxygen. It returns to the two chambers on the left side of the heart which pumps blood out to all of our arteries feeding all of our cells and vital organs. The two upper chambers on each side are called atria and the two bottom chambers are called ventricles.

The wall in between the chambers on the right and left sides is called the septum. The septum is where the electrical impulses are automatically generated and sent down the pathways or “wires” to make the heartbeat. This is the only muscle in the body that is able to generate an electrical impulse. The overall structure of the heart makes it an efficient and never ending pump so this muscle in your body needs to be strong.1

Interested in learning more about your Cardiovascular System? Check out these related articles:


  1. The Franklin Institute. The Human Heart: Structure of the Human Heart. 2015.
  2. Yale-New Haven Hospital. How the Heart Works. 2015.
  3. National Geographic Society. Heart. 2015.