Certain cancer treatments may increase your risk of developing different heart problems in the future. But many people who have these drugs or treatments do not develop any effects.

Treatments that can effect the heart include:

Chemotherapy

• types of anthracyclines: doxorubicin, epirubicin, idarubicin and mitoxantrone
• 5FU (5-flourouracil)
• high dose cyclophosphamide
• capecitabine
• cisplatin
• cytarabine
• paclitaxel and docetaxel.

Radiotherapy

Having radiotherapy to the chest or the mid to upper back (thoracic spine) can sometimes cause heart problems. Total body irradiation (TBI) can also cause heart problems.

Targeted therapies

Targeted therapies are drugs that target certain proteins on the surface of cancer cells.

Monoclonal antibodies are a type of targeted therapy that can affect the heart. The most common ones used to treat young people are rituximab and trastuzumab (also known as Herceptin®). There are other targeted therapy drugs that do not affect the heart. It is best to read the information about the individual drugs you’ve had.

Most young people treated for cancer will not develop heart problems.. If you have had treatment that could affect your heart, your doctor would have told you about this before you started treatment. Sometimes, a heart problem can develop many years after finishing treatment.

Even when your treatment has finished, you might still need to have some tests. This means they can find any problems and treat them early.

The symptoms of a heart problem can vary from mild to severe. They can affect people in different ways.

Tell your hospital doctor or GP straight away if you have any of the following symptoms:

• shortness of breath
• dizziness, light-headedness or fainting
• feeling or being sick
• swollen feet and ankles
• feeling like your heart’s racing or skipping a beat
• coughing or wheezing that doesn’t go away
• pain in your chest that might spread to your arm
• a sharp pain on the left side of your chest that’s often worse when taking a deep breath.

Possible heart problems

Remember, a lot of these problems are rare and can vary from mild to severe. Here are some of the heart problems that can happen after cancer treatment:

• Damage to the muscle cells around the heart might mean the heart can’t relax and contract normally (cardiomyopathy or left ventricular dysfunction).
• The protective covering around the heart might become inflamed (pericarditis). It can also get scarred.
• The valves in the heart can become stiff or leaky (valvular stenosis or insufficiency).
• Damage to the heart’s electrical pathways can cause abnormal heart rhythms (arrhythmias), such as a fast, slow or irregular heart rate.
• If the heart’s blood vessels become scarred or blocked, it can be harder for oxygen and other nutrients to get to the heart and other organs (coronary heart disease).

Tests for heart problems

Your doctor will tell you exactly what follow-up you need. The most common heart test is an echocardiogram (an ultrasound scan of your heart).

Sometimes, you may have other tests, including:

• An electrocardiogram (ECG)
• a MUGA scan
• blood tests.

If you have any questions about these tests, ask your doctor or nurse. They can tell you what tests you might need, and how long after your treatment you will need them for. It is important that you get the right follow-up.

How often you need these tests depends on what the heart problem is and how severe it is. It also depends on what else is happening in your life. For example, if you're pregnant or planning to have a baby, the doctor might do them more often. This is because of the extra strain pregnancy can cause.

It’s important to know which cancer treatments you’ve had, because some heart problems can happen years later. Your doctor will write them down in your medical records, but it’s helpful if you keep a note of them, too.

Looking after your heart

It can be worrying to read about things going wrong with your heart. But remember, heart problems after cancer treatment are rare. There are things you can help reduce the chance of heart problems.

If you smoke, it’s a good idea to quit. There is lots of help and support for you. You can ask your GP or pharmacy for advice. You can also have a look at the NHS Better Health website.

You can help keep your heart healthy by having a healthy diet and keeping to a healthy weight. Exercising regularly also helps. But if you’ve had certain chemotherapy drugs, your doctor may advise avoiding heavy weight lifting for the rest of your life. This is because it can put too much strain on your heart. These drugs include doxorubicin, idarubicin and epirubicin, which all belong to a group of drugs called anthracyclines.

For more information on the effects on the heart, please follow the below links:

Heart problems | CCLG - The Children & Young People's Cancer Association

Late effects - Heart issues | CCLG - The Children & Young People's Cancer Association

Understanding the late effects of cancer treatment | Macmillan Cancer Support