Patients & Family

The heart

The heart at work


Location and main function of the heart


Your heart is an organ made of muscle and is located in the centre of your chest. It is enclosed in your rib cage, behind your chest bone and between your lungs.


The main job of your heart is to pump blood through your body. The blood contains oxygen and other important nutrients that your body needs to work properly. The other organs of your body (for example your brain, kidneys, and liver) will stop working if they don't get oxygen and nutrients from the blood.


The heart’s structure


Your heart is divided into four sections, called chambers


The top two chambers of your heart are called the atria and their function is to receive blood. There is a left atria and a right atria. The bottom two chambers of your heart are called the ventricles and their function is to pump blood. There is a left ventricle and a right ventricle.


The atria and ventricles are like separate rooms with doors between them. The doors between the atria and the ventricles are called valves. Valves make sure that the blood flows between the atria and ventricles in one direction only.


The flow of blood through the heart


Your heart is part of your circulatory system, which also includes your blood vessels and lungs. Blood flows continuously through your circulatory system to keep your body supplied with oxygen and nutrients.


When blood reaches the heart, it flows into the atria, and from the atria into the ventricles - first through the right atrium and ventricle and then through the left atrium and ventricle.


In a healthy heart, all the chambers work together in perfect time to control blood flow. During a single heartbeat (one ‘lubb-dubb’), the chambers contract and relax, the valves open and close, and the blood flows through.


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