Heart disease

Problems with the heart include:

  • Coronary heart disease – The blood vessels that supply the heart with oxygen can be narrowed by fatty deposits. If this happens, less blood and oxygen reach the heart muscle. Symptoms include chest pain and breathlessness. A heart attack may happen if the blood flow to the heart is blocked. Symptoms of a heart attack can include chest pain or tightness which may spread to your arms, neck, jaw, stomach or back. You may also feel dizzy or short of breath.
  • Heart muscle damage and heart failure – If the heart is damaged, it becomes weaker and can’t pump blood very well. Symptoms of heart failure can include shortness of breath, tiredness and swollen ankles.
  • Heart valve disease – The valves in the heart may not be able to open or close properly. This can affect the flow of blood through the heart. This may cause symptoms of heart failure.
  • Electrical heart disease (arrhythmia) – This is a fault in the system that keeps the heart beating properly. It can cause it to beat too quickly or too slowly.

Coronary heart disease

The blood vessels (see our information on the heart) that supply the heart muscle with oxygen can become narrowed by a gradual build-up of fatty deposits (atheroma) within their walls. This is called coronary heart disease or coronary artery disease. When this happens, less blood and oxygen reach the heart muscle.

Symptoms of coronary heart disease (angina) include:

  • chest discomfort or pain, and tightness
  • pain that spreads to your shoulders, neck or arms
  • shortness of breath, especially when you are exerting yourself.

A normal artery and a narrowed artery
A normal artery and a narrowed artery

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Sometimes the fatty deposit can split. If it does, a blood clot can form inside the artery. This can block the flow of blood completely and stop parts of the heart muscle getting enough blood. This causes a heart attack and can result in permanent damage to the heart muscle.

Symptoms of a heart attack vary from person to person, but can include:

  • severe, central chest pain
  • mild chest discomfort, ache or heaviness
  • feeling generally unwell
  • pain that spreads to the arms, neck, jaw, stomach or back
  • shortness of breath
  • feeling dizzy and sick (nausea)
  • being sick (vomiting).

Smoking and having high levels of cholesterol in your blood (see Risk factors and your heart) can increase your risk of coronary heart disease. The risk can also be increased by some cancer treatments.


Heart muscle damage and heart failure

Damage to the heart muscle weakens it. This makes it harder for the heart to pump blood efficiently.

The heart muscle can be damaged by:

  • a heart attack
  • high blood pressure over a long period of time
  • some infections
  • problems with the heart valves or heart rhythm
  • coronary heart disease
  • diabetes
  • heavy alcohol consumption
  • some cancer treatments.

You may hear doctors talk about heart failure. This is when a person’s heart can’t pump blood around the body as well as it used to. Heart failure doesn’t mean that the heart stops working, just that it becomes weaker. Symptoms of heart failure can include:

  • feeling short of breath (breathless), especially during activities such as walking up stairs, and when lying flat at night
  • increasing fatigue (extreme tiredness) – for some people the fatigue may be overwhelming
  • swollen ankles.


Heart valve disease

The heart valves can become damaged or diseased. They may become too stiff and can’t open properly. Or they may not close tightly enough and become leaky. This causes blood to leak backwards through them. This affects the flow of blood through the heart and puts strain on the heart muscle to work harder. Over time, if not treated, it can cause the symptoms of heart failure.

Problems with the heart valves can develop as you get older. They may be caused by coronary heart disease, infection, high blood pressure over a long period of time, and radiotherapy (when it includes the heart area – see our information on radiotherapy and how it affects the heart).

Some people are born with an abnormal valve. This is known as congenital heart valve disease.


Electrical heart disease (arrhythmia)

A fault in the electrical system that keeps the heart beating can cause the heart to beat either too quickly, too slowly or irregularly. This can lead to the sensation of a racing heart beat (palpitations) or dizzy spells. Rarely, a person may blackout (lose consciousness or faint).

An abnormal heartbeat is more common in people who are older or who have coronary heart disease or heart valve disease. Some cancer treatments can also affect the electrical system and how the heart beats.


Working together to create information for you

We worked with British Heart Foundation to write our content on heart health.

Thank you to all of the people affected by cancer who reviewed what you're reading and have helped our information to develop.

You could help us too when you join our Cancer Voices Network.

Back to Looking after your heart

The heart

The heart is a large muscle. It pumps blood around your body to deliver oxygen and nutrients.

Risk factors and your heart

Some factors can increase your risk of developing heart problems. Improving your lifestyle can lower your risk.

Keeping your heart healthy

You can help keep your heart healthy by eating well, keeping active, controlling stress and giving up smoking.

Top ten tips for heart health

Try following these 10 tips to keep your heart healthy. You can try these before, during and after cancer treatment.