Your heart is a vitally important pump which beats every second of everyday pumping blood around your body. Since you only have one heart, you really need look after it as best you can.

Its design is incredibly complex with many different parts some moving, some muscular, and some electrical – let’s try to simplify these elements and give an overview of your hearts structure and function.


A normal heart is made up on four rooms or chambers each of which has a specific role.

The top chambers are called the Right Atrium and Left Atrium; these collect the blood returning from the body and lungs (blood freshly refilled with oxygen) respectively.

The bottom chambers are called the Right Ventricle and Left Ventricle; these are the two pumping chambers, pumping blood to the lungs (blood to be topped up with oxygen) and around the body respectively.

Separating the heart chambers are valves made of tough flexible tissue which open and close in response to pressure changes within the heart chambers. These are the doors controlling the smooth flow of blood through your heart ensuring it is working as efficiently as possible.


The Left Ventricle is usually the largest and most muscular heart chamber as its primary function is to pump blood (freshly topped up with oxygen by the lungs) out of the heart and around your body delivering oxygen and nutrients to your brain, organs, muscles and tissue. 

During each heartbeat, the Left Ventricle contracts and squeezes, forcing blood out of the heart along blood vessels called arteries. In doing so it generates and maintains pressure within the arteries to keep your blood flowing.

The volume of blood being forced out of your Left Ventricle generates an increased pressure within the arteries which reaches a peak pressure called Systolic Blood Pressure.

Soon the Left Ventricle finishes contracting and starts to relax again. As the muscular walls relax, the Left Ventricle refills with blood from the Left Atrium getting ready for the next contraction.

This relaxation between heatbeats causes the blood pressure in the arteries to drop to its resting level called Diastolic Blood Pressure.

The pressure wave of blood travelling along the inside of the arteries is the pulse you feel when you check to see how fast your heart is beating.


Very little would happen in your body without a small bit of electricity? This is especially true of muscles, which need a small electrical stimulation to trigger them to contract. Since your heart is a muscular pump, every heartbeat is immediately preceded by a small electrical stimulation.

The hearts electrical stimulation starts high up in the Left Atrium and spreads across the two top chambers (the Atria) before reaching the mid-point between the top and bottom chambers. Here, there is a short delay as the electrical signal can only travel along one nerve fibre from the atria to the ventricles.

Once through, the electrical stimulation travels fast along nerve fibres within the muscular walls of the ventricles causing them to contract.

After a short recharge time, another electrical stimulation starts following the same pathway.