Chemotherapy side effects: A cause of heart disease?

Can chemotherapy increase the risk of heart disease?

- Judy / Minnesota

Mayo Clinic oncologist Timothy Moynihan, M.D., and colleagues answer select questions from readers.

Answer

Chemotherapy side effects may include an increased risk of heart disease, especially weakness of the heart muscle (cardiomyopathy). Fortunately, heart disease associated with chemotherapy is relatively rare and typically occurs only with certain types of chemotherapy.

If your doctor is considering using a chemotherapy drug that may affect your heart, he or she may test your heart function before starting treatment. During treatment, you may require periodic monitoring of your heart function. If you have a pre-existing heart condition, such as cardiomyopathy, your doctor may suggest a different type of chemotherapy.

With the most commonly used chemotherapy drugs that may affect the heart, the risk of heart disease increases with the total lifetime amount of the drug you receive. To minimize the risk of heart damage, your doctor will carefully monitor the amount of each type of chemotherapy you receive to ensure you stay within safe guidelines.

Certain types of chemotherapy also increase the risk of heart attack, especially during infusion of the medication. If you experience any chest pain or other symptoms of a heart attack during chemotherapy, you should report this immediately to your doctor or nurse.

Some newer anti-cancer treatments, such as trastuzumab (Herceptin) for breast cancer, may cause heart damage. However, this side effect is rare and may be reversible. While you are using this drug, your doctor will very closely monitor your heart function.

In addition, some cancers require radiation therapy. If the area of your body receiving radiation includes your heart, you have an increased risk of cardiomyopathy, coronary artery disease and heart attack. The combination of radiation and chemotherapy can further increase your risk of heart damage.

Your oncologist will take precautions to reduce the risk of heart disease related to your cancer treatment.