What are the Four Chambers of the Heart?

The heart is a muscular organ responsible for pumping blood around the body. The heart has a four-chamber system to enable oxygenated blood and deoxygenated blood to be kept separate from each other. The heart pumps oxygenated blood from the lungs to the body and deoxygenated from the body to the lungs to enable re-oxygenation.

In this first aid blog post we will look at the four chambers of the heart in more detail and how blood moves through these chambers.

What are the Four Chambers of the Heart?

The four chambers of the heart are the: left atrium, left ventricle, right atrium and right ventricle.

The four chambers of the heart

The ventricles have the responsibility of creating a force big enough to push the blood around the body. Therefore, the ventricle muscular tissue is much thicker than that of the atria. Because the left ventricle is responsible for pushing oxygenated blood around the whole body, it has even more muscular tissue compared to the right ventricle which is only transporting deoxygenated blood a relatively short distance to the lungs.

Blood flow through the heart is in a particular direction; a cycle. Oxygenated blood from the lungs arrives into the left atrium from the pulmonary vein. This then passes into the left ventricle which contracts strongly to push the blood into the aorta which will transport the blood around the body.

After collection from the body tissues, the now deoxygenated blood enters the right atrium from the superior and inferior vena cava. The blood then enters the right ventricle which contracts to push the blood into the pulmonary artery, transferring the blood back to the lungs for re-oxygenation.

Like a boiler or engine system, the heart requires valves to prevent backflow of blood in the wrong direction. There are four valves in the heart, which separate the atria from the ventricles and the ventricles from the aorta and pulmonary artery. There are four heart valves:

  • Mitral valve – Separates the left atrium from the left ventricle
  • Aortic valve – Separates the left ventricle from the aorta
  • Tricuspid valve – Right atrium into the right ventricle
  • Pulmonary valve – Separating the right ventricle and the pulmonary artery.

Damage to the valves can cause backflow of blood if they are not able to close properly. This is called regurgitation. Patients with regurgitation develop dilated ventricles and atria at they have to work harder to push blood out of them. If the valves become stiff or narrowed (called stenosis), the blood flow through them gets restricted and therefore not as much blood is ending up where it should be and the heart has to work harder to push blood out

John Furst

JOHN FURST is an experienced emergency medical technician and qualified first aid and CPR instructor. John is passionate about first aid and believes everyone should have the skills and confidence to take action in an emergency situation.

You may also like...

First aid links

3 Responses

  1. Andrew Kandia Carlo says:

    Very helpful training.

  2. mchemwalocardia@gmail.com says:

    Thank you so much for your classes really appreciate your good work

Leave a Reply