Cancer treatment helps patients survive longer, amounting to over 18 million cancer survivors (or more than 1 in 20 people) alive today. These numbers are expected to grow rapidly over the next few years, with a projected 24.4% increase in survivors — to 22.5 million by 2035. 

While this is a clear indicator of the benefits of cancer treatment, there are still some side effects that can occur, such as heart damage. 

Heart damage that occurs from cancer treatment is called cardiotoxicity. Treatments such as chemotherapy, radiation therapy, and targeted therapy drugs can cause problems like abnormal heart rhythms, high blood pressure, and heart failure. 

Here’s an overview of cardiotoxicity and how it might play a role in your or a loved one’s cancer care. 

Cancer Treatment and the Heart

Cancer treatment can affect many parts of the body, including your organs. For instance, chemotherapy and radiation are designed to destroy cancer cells while keeping healthy tissue safe. But in some cases, it can cause damage to healthy cells in the process. 

Certain cancer treatments can make it harder for the heart to do its job of pumping blood throughout the body. This can cause long-term effects, some of which may not show up for years or decades after treatment has ended. 

Cardiotoxicity can lead to heart problems including: 

• Low or high blood pressure 
• Arrhythmia (irregular heartbeat) 
• Blood clots
• Cardiomyopathy (when your heart can’t pump blood to your body efficiently) 
• Coronary artery disease (when your blood vessels aren’t able to send enough blood to the heart) 
• Heart valve disease (when the valves in your heart don’t work properly) 
• Heart attack
• Heart failure

Cardiotoxicity Risk Factors 

While cardiotoxicity can affect anyone who has gone through cancer treatment, your risk of developing heart problems depends on many factors, such as what kind of treatment you have and what dosage you’re given. 

Cardiotoxicity is more likely to occur in those who: 

• Have taken certain medications, such as immunotherapy medications 
• Had radiation to the chest
• Had cancer treatment as a child 
• Had heart problems prior to cancer treatment 

Preventing and Monitoring For Cardiotoxicity 

If your cancer treatment puts you at risk of heart damage, your provider may recommend heart testing before beginning treatment. By discussing your health history with your cancer care team before beginning treatments, you can review the risks and benefits of treatment options. 

While there’s no way to prevent heart damage from certain cancer treatments, you can be monitored for effects. Regular heart imaging (such as echocardiogram and cardiac MRI) can detect signs of cardiotoxicity early, when they’re easier to treat. 

You can also be on the lookout for symptoms of cardiotoxicity, such as: 

• Chest pain
• Heart palpitations (which can feel like pounding or flip-flopping heartbeats) 
• Increased coughing
• Shortness of breath
• Dizziness
• Enlargement of the abdomen
• Swelling in the legs 

Your Cardiotoxicity Treatment Plan

Treating cardiotoxicity depends on your cancer care plan. In some cases, your provider might decrease the dosage of some medications or stop them altogether. You may also be given medications to treat heart damage, such as ACE inhibitors, beta-blockers, or vasodilators. 

Your oncologist may work with a heart specialist (cardiologist) to determine the best treatment approach for your situation. 

Cardiotoxicity can be reversed, depending on what kind of cancer treatment you’ve had. For instance, reversing heart damage from certain medications is often more successful than when it occurs from radiation to the chest. 

Continued Research on the Effects of Cancer Treatment on the Heart

Researchers are still learning more about how certain cancer treatments can damage your heart as well as cause other long-term side effects. Their research will continue to make advancements in this field to better care for patients, their heart health, and their overall well-being. 

Meanwhile, being aware of your own heart health as you undergo cancer treatment is key. By talking to your cancer care team and other healthcare providers, you can ensure you make the most informed decisions to keep you and your heart healthy.