What is the heart?

It’s about the size of a fist and is well protected by the rib cage.

It’s made of some of the cleverest muscles in your body – cardiac muscles!

Cardiac muscles are pretty tough!

Cardiac muscles contract and relax. The contracting and relaxing pushes blood all around your body.

The cells in your cardiac muscle are programmed to do this contracting and relaxing, all by themselves, over and over again without you ever thinking about it!

Did you know?

Over the average lifespan, a human heart will beat over 2.5 billion times! If you could add up the power in all those beats, it would be enough to lift a battleship!

What’s inside the heart?

Inside the heart there are four chambers.

A chamber is just like a room – there’s two on the bottom, two on the top.

The chambers on the bottom are called the ventricles. Their job is to push blood around the body.

The two chambers on top are called the atria. These chambers fill with the blood returning to the heart from around the body.

Running down the middle of the heart is a thick wall of muscle called the septum which separates the left and right side of the heart.

Can you get holes in your heart?

Yes, you can. Sometimes there are holes between the chambers of the heart.

If you’ve ever had a hole in your bike tyre or in a bottle of water, you’ll know holes can stop things from doing their job properly. Holes in the heart can cause problems like blood traveling in the wrong direction.

These holes shouldn’t be there but some people are born like this. When someone is born with a condition, it’s called congenital, so these holes are known a congenital heart condition.

Some holes are tiny and are left alone, others are much bigger and operations can help to close them to help the heart do its job.

They’ll be finding out all about the cool stuff that goes on inside your heart and how it manages to pump blood around your body all the time – even when you’re asleep!