Possible late effects of breast cancer treatment on the heart

You will have been monitored closely during and after treatment to reduce the risk of this happening. And most women won’t ever experience any effects on the heart. But it may help to understand more about it and how you can help look after your heart. 

Treatments Back to top

Chemotherapy|, radiotherapy|, hormonal treatments|, trastuzumab (Herceptin)| and early menopause| can change the way the heart works.

The standard chemotherapy for early breast cancer usually includes drugs known as anthracyclines (epirubicin| or doxorubicin|). This is an effective treatment for breast cancer as evidence shows that these drugs are better at reducing the risk of it coming back. 

In some women, treatment with anthracyclines may result in an increased risk of heart problems, usually much later in life. Women are carefully monitored before and during their treatment to find out if they’re at more risk so that their treatment can be changed. And many women who have these drugs won’t ever experience heart problems.

Radiotherapy is now very carefully planned to avoid including the heart in the treatment area. So it rarely causes heart problems and only women who have cancer in their left breast are at risk.

Having an early menopause due to your treatment may also increase the risk of heart problems. This is because oestrogen and progesterone help protect the heart. Hormonal drugs, called aromatase inhibitors, may also increase the risk of heart problems.

Trastuzumab (Herceptin) can damage the heart, so it’s not given to women with heart conditions. Tests are done before treatment and women are checked regularly throughout and after treatment.

Symptoms Back to top

We’ve included a list of symptoms that can be linked with heart problems. But they can be caused by lots of other things. As problems can occur many years after treatment, you may need to remind your doctor of the cancer treatments you had in the past.

Let your doctor know if you have any of these symptoms:   

• feeling your heart beating fast, hard or irregularly
• pain or discomfort in your chest
• getting breathless, for example when climbing stairs
• feeling weak or dizzy
• getting tired very easily
• swelling of your feet and lower legs.

If you have heart problems, your doctor will refer you to a heart specialist (cardiologist).

What you can do Back to top

Making small changes to your lifestyle can reduce your risk of developing heart problems. And even if you already have problems, small changes can help to reduce your risk of further problems.

Look after yourself

Take enough exercise, eat a healthy diet, reduce your stress and be aware of dangers such as smoking and drinking too much. The British Heart Foundation| has lots of information and advice on keeping your heart healthy.

Exercise Regular exercise can help keep your heart healthy and has other benefits too. It helps you to keep to a healthy weight and reduces your risk of bone thinning (osteoporosis). It can help reduce stress and improve fatigue and you’ll look and feel better.

There’s also some evidence that regular exercise may help to reduce the risk of breast cancer coming back and your risk of getting some other cancers.  

Eat healthily and cut down on alcohol

Eating healthily helps to protect your heart and keeps your weight healthy as well. Try to eat five portions of fruit and veg a day, eat more chicken and fish (especially oily fish) and high fibre foods. Eat less saturated fats (pastries, cakes, cheese), less red processed meat and cut down on salt.

After breast cancer, some women want to know if they should avoid dairy foods or if there’s a particular diet they should follow. Studies have looked for a link between diets that are high in dairy products and breast cancer but haven’t shown a clear link. So cancer experts don’t recommend following a dairy-free diet.

There’s also a lot of publicity about alternative diets for treating cancer, but there is no evidence that these diets increase a person’s chance of survival. Some of these diets may lack important nutrients or be unbalanced in other ways and may even be harmful.

Doctors and specialist nurses recommend a healthy, well-balanced diet and one that you enjoy.

Our section on eating well| after cancer treatment has more information.

Too much alcohol can cause heart problems and it’s high in calories. There’s some evidence that drinking small amounts of alcohol might help to reduce the risk of heart disease, at least in middle-aged people. Stick to sensible drinking. Current guidelines recommend that men drink less than 3 units of alcohol per day, or 21 per week and women drink less than 2 units per day, or 14 per week.

Stop smoking

If you’re a smoker, giving up is the healthiest decision you can make. It’s one of the major risk factors for heart disease. Stopping smoking also reduces your risk of lung disease, bone thinning (osteoporosis) and smoking related cancers. You’ll also feel and look better.

Giving up smoking isn’t easy but you can increase your chance of success by preparing for possible problems in advance, and making sure that you have support in place to help you overcome them. Using a treatment to reduce cravings can double your chances of success. There’s a range of treatments that can be prescribed. Your GP can tell you about them and help you choose the one which is best for you.

Our section about stopping smoking| has more advice and tips to help you succeed.