How to Protect Your Heart During Breast Cancer Treatment: Top Strategies and FAQs for Cardiotoxicity Prevention

Like all types of medical care, treatment for breast cancer comes with both benefits and risks. Although a number of studies have found an association between some types of breast cancer treatments and an increased the risk of heart failure and other types of heart disease, known as cardiotoxicity, there are steps women can take to mitigate those risks. The first step is to talk with your oncologist, primary care physician, and a cardio-oncologist (a specialist who focuses on helping people with cancer prevent and manage heart disease) about steps you should take to mitigate the risk, what symptoms could mean you were experiencing heart problems, and what lifestyle changes you can make to manage pre-existing heart disease or lower the risk of developing heart disease during and after treatment.

What breast cancer treatments are associated with an increased heart disease risk?

Certain chemotherapy drugs, radiation therapy, especially to the left breast, and targeted therapies and immunotherapies can have a negative effect on the tissue of the heart.

• Chemotherapy: Some drugs in the anthracycline and taxane classes of chemotherapies, including Adriamycin (doxorubicin), Doxil (doxorubicin), and Ellence (epirubicin), can damage heart muscle cells, increasing the risk of cardiomyopathy (weakening of the heart muscle) and heart failure.
• Targeted therapy and immunotherapy: Herceptin (trastuzumab) and Perjeta (pertuzumab), which are monoclonal antibodies used to treat HER-2 positive breast cancers, increase the risk of cardiomyopathy and heart failure in some women. They may also cause arrythmias, blood clots, and enlargement of the heart. These side effects also occurred in women who took medications that contained Herceptin and another drug, including Herceptin Hylecta, Kadcyla, and Phesgo. Other medications that have been associated with cardiotoxicity include Tykerb (lapatinib), while Kisqali (ribociclib) has been associated with a risk of long QT syndrome, which causes fast, irregular heartbeats. Researchers found the risk of heart problems to be highest in women who received both anthraclyclines and trastuzumab.
• Radiation therapy: Radiation therapy can scar heart tissue and damage the major blood vessels around the heart, which many increase the risk of heart valve disorders and coronary artery disease. This is an issue particularly for women with cancer in the left breast due to the heart’s location.
• Hormonal therapy: These medications, which fall into the category of aromatase inhibitors, can increase the risk of developing high cholesterol, which in turn can cause heart problems like heart attack and stroke.

In addition to affecting the heart, targeted therapy, immunotherapy, and radiation therapy can all cause lung problems, so be aware of new symptoms like shortness of breath, dry cough, wheezing, and chest pain and let your treatment team know if you experience any of these symptoms.

Strategies to protect the health of your heart

To manage the potential heart-related risks of breast cancer treatment, build a multidisciplinary care team that can help you manage any existing heart disease, recommend strategies to lower your risk of developing treatment-related heart problems, and monitor your heart health before, during, and after treatment for the long term. In addition to the medical specialists on the team (oncologist, cardio-oncologist, cardiologist, and primary care provider), your health advisor can also be a valuable resource. Your advisor can help connect you with specialists, ensure your complete medical record is delivered to all the providers who treat you, and provide you with evidence-based information about your condition, treatment options, and clinical trials.

These steps can help you protect the health of your heart during and after breast cancer treatment:

• Get your heart health assessed: If possible, before starting treatment, see a cardiologist or cardio-oncologist to find out if you have undiagnosed heart disease or factors such as high blood pressure, cholesterol, or blood sugar that increase your risk for heart disease and to develop a plan to lower your risk. If you’ve already been diagnosed with heart disease, talk with your cardiologist and primary care provider about whether your cancer treatment may affect how you manage your heart disease.
• Talk to your oncologist: Ask what potential risks your treatments present, if there are ways to lower those risks—such as taking beta blockers, statins, or ACE inhibitors, which have been found to decrease the risk of heart damage from some types of breast cancer treatment—and how your heart health will be monitored during and after treatment. If radiation therapy is part of your treatment plan, ask if there are therapy options that can reduce your risk of post-treatment heart issues, such as more targeted forms of radiation like proton beam therapy, intensity-modulated radiation therapy, and intra-operative radiation, prone positioning (laying face down with the breast suspended away from the body during treatment), and deep inspiration breath-hold (a breath holding technique that temporarily moves your heart away from the radiation target area.
• Learn the symptoms to watch for: Ask your doctor to outline the symptoms of treatment-related heart disease. For example, people with heart failure may have shortness or breath, swelling in the legs, feet, and ankles, fatigue and weakness, rapid or irregular heartbeat, and rapid weight gain from fluid retention. People with cardiomyopathy have many of the same symptoms plus stomach bloating, dry cough, chest pain, dizziness, and fainting. Stroke symptoms can include drooping of one side of the face, weakness or numbness in one arm, slurred speech, confusion, trouble seeing, loss of balance or coordination, and a severe headache.
• Make sure your medical record includes the specifics of your breast cancer treatment: If you have to seek emergency treatment for symptoms that could be caused by cardiovascular disease or damage, it’s important for all the physicians treating you to know what types of breast cancer treatment you’re undergoing or have undergone.
• Make heart healthy lifestyle changes: Studies have found that regular physical activity both improves survival and reduces the risk of heart injury from breast cancer treatment, so strive to get at least 30 minutes of aerobic exercise 5 or more days a week. Eating a healthy diet can also lower your risk of heart disease, as can reaching and maintaining a healthy weight. Don’t smoke, avoid or limit alcohol, and work with your doctor to keep your blood pressure, cholesterol, and blood sugar levels under control.

Connect with PinnacleCare

For more information about how PinnacleCare could support you and your heart health during breast cancer treatment, connect with us today.

PinnacleCare is a member of the Sun Life Financial Inc. (“Sun Life”) family of companies. PinnacleCare and its employees do not diagnose medical conditions, recommend treatment options or provide medical care, and any information or services provided should not be considered medical advice. Any medical decisions should be made only after consultation with and at the direction of your medical provider. Any person or entity who provides health care services following a referral or other service provided does so independently and not as an agent or representative of PinnacleCare.

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