Overview
Heart problems such as blood clots, heart failure and heart attack may develop or get worse during or after some types of cancer treatment.
Symptoms of heart problems to look out for include chest pain or tightness, shortness of breath, swelling in the legs and feeling faint or dizzy. Your heart health may be checked before you start cancer treatment.
What's on this page
Common heart problems linked to cancer and its treatment
Heart problems may develop or worsen during or after some types of cancer treatment.
Angina and heart attack
Angina and heart attack
What it means
When fats or other substances build up in the blood, blood vessels can become blocked (atherosclerosis). This can reduce the amount of blood flowing through the heart. It may cause:
- angina – pain or tightness in the chest when not enough blood is flowing to the heart. This needs to be checked because it may also be a symptom of a heart attack
- heart attack – pain in the chest due to permanent damage to the heart. This needs emergency treatment.
Risk may increase with some types of:
- chemotherapy
- immunotherapy
- radiation therapy to the chest for certain cancers
Blood clots
Blood clots
What it means
Blood clots are clumps of blood that can block blood vessels.They may cause serious conditions including:
- stroke – when the blocked blood vessel restricts blood flow to the brain (called an ischaemic stroke). Strokes can also be caused by bleeding in the brain if an artery leaks or splits (called a haemorrhagic stroke)
- pulmonary embolism (PE) – when a blood clot blocks the supply of blood to the lungs; this can be life-threatening
- deep vein thrombosis (DVT) – when a blood clot forms in a deep vein, often in the leg; can lead to pulmonary embolism.
Risk may increase with some types of:
- cancer
- chemotherapy
- hormone therapy
- immunotherapy
- ports, etc.
- radiation therapy to the chest for certain cancers (may increase stroke risk, not PE or DVT)
- surgery
- targeted therapy
Heart failure
Heart failure
What it means
Damage or weakening of the heart muscle (cardiomyopathy) may mean the heart becomes too weak to pump blood around the body properly. This can cause shortness of breath and fatigue. Cardiomyopathy must be treated quickly to prevent it becoming permanent.
Risk may increase with some types of:
- chemotherapy
- immunotherapy
- radiation therapy to the chest for certain cancers
- targeted therapy
Heart inflammation (myocarditis)
Heart inflammation (myocarditis)
What it means
When the heart muscle (myocardium) becomes inflamed (swollen or irritated) it can affect the heart’s ability to pump blood. This may cause chest pain, shortness of breath and rapid or irregular heartbeats, and can be life-threatening if not treated early.
Risk may increase with some types of:
- immunotherapy
- radiation therapy to the chest for certain cancers
Irregular heartbeats (arrhythmia)
Irregular heartbeats (arrhythmia)
What it means
The heart has an electrical system that tells it to beat. If this system is not working properly, it can lead to a heartbeat that is irregular (beating too fast or too slow). This is called arrhythmia. For example, atrial fibrillation (AF) is an irregular heartbeat that is often faster than usual. Arrhythmia can cause you to be light-headed or dizzy and, in some cases, to faint. It may also be a sign of heart attack, heart failure or heart inflammation (myocarditis, see above).
Risk may increase with some types of:
- chemotherapy
- immunotherapy
- radiation therapy to the chest for certain cancers
- targeted therapy
Other cardiovascular concerns
Other cardiovascular concerns
What it means
Cancer treatments may also affect the heart by causing:
- high blood pressure (hypertension) – when the force of the blood pushing against the artery walls is too high for a long time or the arteries become stiff, the heart has to work harder to pump blood. This increases the risk of heart attack and stroke
- high cholesterol (hyperlipidaemia) – a build-up of fats (lipids) in the blood. This increases the risk of heart attack, stroke and kidney damage
- high blood sugars (hyperglycaemia) – when there is too much glucose (sugar) in your blood. This increases the risk of heart attack, angina and stroke.
See your GP for regular check-ups for these issues.
Risk may increase with some types of:
- chemotherapy
- hormone therapy (e.g. androgen deprivation therapy)
- immunotherapy
- targeted therapy
Symptoms to look out for
Watch for early signs that something may be wrong with your cardiovascular system. Some symptoms may not be related to the cancer or its treatment; your doctor will consider other possible causes.
Chest pain or tightness
Chest pain or tightness
This may feel like heavy, crushing pain or pressure in your chest, back, neck or jaw. It may also feel like sharp, stabbing pain.
Shortness of breath
Shortness of breath
This is when you feel that you cannot get enough air into your lungs. It’s normal to feel this way after exercise or physical work, but if it feels worse than usual or happens for no reason, this may be a sign of heart problems.
Swelling in the legs
Swelling in the legs
If your heart is not pumping blood around the body as well as it should, blood and other fluids can build up in your legs, ankles and feet. This is called oedema. It can also be a side effect of some cancer treatments.
For more information, see Lymphoedema.
Fatigue
Fatigue
This is extreme tiredness and lack of energy that usually does not go away with rest.
For more information, see Fatigue.
Feeling faint or dizzy
Feeling faint or dizzy
You may feel light-headed, unsteady on your feet, or notice changes in your vision.
Abnormal heartbeat
Abnormal heartbeat
Your heart may beat faster than usual (heart palpitations) or in an abnormal way (irregular heartbeat). This may happen when the heart’s electrical signals aren’t working properly.
Other symptoms
Other symptoms
These may include:
- pain in the arms or shoulders
- indigestion
- unexplained perspiration (feeling sweaty)
- or unexplained nausea (feeling sick)
- vomiting.
These symptoms are more common in women, but can also affect men. For more information about heart health for women, visit Her Heart.
If symptoms are severe or come on suddenly, call Triple Zero (000) or go to your nearest emergency department. Be sure to tell the emergency doctors about your cancer treatment.
Prevention and monitoring
Before treatment
Your heart health may be checked before you start cancer treatment. It’s important that your treatment team knows about any existing heart problems or risk factors (e.g. high blood pressure, high cholesterol, diabetes) so they can recommend the safest and most effective cancer treatment for you.
The doctor may ask you about your risk factors for developing heart problems and any previous heart issues or cancers you’ve had. They may also suggest changes you can make to improve your heart health.
To work out your overall risk of heart problems, your doctors will consider:
- your heart health before treatment
- any risk factors you have
- if the cancer treatments could affect your heart.
If you don’t have heart concerns and your treatment plan does not include treatments that might affect your heart, you may not need to have any heart tests.
If you have risk factors for cardiovascular disease or are receiving cancer treatment that may affect your cardiovascular system, then you may need some tests. You may have these before cancer treatment starts (called baseline tests). Any further tests can then be compared with the results of baseline tests to check for any changes in your heart during and after treatment.
During and after cancer treatment
After having some of the tests, your risk of developing heart problems will be assessed as low, moderate, or high and very high. This helps your doctors work out a treatment plan, and how closely to monitor your heart during and after your treatment.
Your heart risk may change over time. It’s important to tell your GP or cancer treatment team if you notice any symptoms that could be related to your heart. When found early, heart problems can usually be managed and are less likely to become serious.
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