Breast Cancer Treatment and Your Heart

Breast cancer treatments may increase the risk of heart disease.

For the 3 million U.S. women who are survivors of breast cancer –not to mention the 266,000 women expected to be diagnosed this year –understanding the links between breast cancer and heart disease is critical. After all, heart disease causes more women’s deaths each year than anything else, and 90 percent of women already have at least one risk factor for heart disease.

Chemotherapy and Heart Disease

There are many types of chemotherapy, but one very common –and effective –type is the anthracycline doxorubicin. Part of how it works is by binding to cancer cells’ DNA to stop them from replicating. This is great for treating breast cancer, but anthracyclines can cause irreversible damage to the heart. 

Chemotherapy can also cause temporary heart problems, such as murmurs and other rhythm issues.

The good news is that chemotherapy does not seem to increase women’s risk of heart disease long-term.

Radiation and Heart Disease

For women treated with radiation therapy, long-term heart disease risk is much more of a concern. Especially for women with cancer in the left breast, which is closer to the heart.

For women being treated with radiation today, the risk of long-term heart damage is likely lower than studies are showing.

For breast cancer survivors who may have received radiation a decade or more ago, just knowing they may be at increased risk of heart disease can help. Women and their health care providers can closely monitor symptoms and early potential signs, such as high blood pressure or high cholesterol.

Risk Factors in Common

Researchers are also finding that breast cancer and heart disease share many of the same risk factors. For example, aging, poor diet, lack of exercise, and smoking all increase your risk for both diseases.