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Chemotherapy drug adversely affects heart function

Posted by Manuela Boyle on 14 December 2023
Chemotherapy drug adversely affects heart function

As the number of cancer survivors increases, it's essential for doctors to ensure cancer treatments don't leave any long-lasting side effects, particularly on heart health.

Heart issues are a major health concern, being the leading cause of death in America, closely followed by cancer. It's crucial to ensure that curing cancer doesn’t result in cardiovascular complications. Certain chemotherapy drugs, like doxorubicin which is used to treat breast cancer, sarcomas, and lymphomas, are known to affect heart function. This effect was once thought to be irreversible, but recent discoveries show that heart-protective medications can actually improve heart function, even years after treatment.

Heart-related side effects from doxorubicin are relatively rare, affecting a small percentage of patients, with slightly higher instances in those treated for lymphoma and sarcoma due to the higher drug doses used. Trastuzumab, a targeted therapy drug, can also impact the heart, but its effects are usually reversible, and less than 1% of patients experience heart function issues with newer targeted therapies.

Radiation therapy, too, can cause heart complications like blockages or valve problems, especially when treating areas close to the heart. That’s why it's important to focus radiation as much as possible on the cancer, minimising exposure to the heart.

Evaluating a patient's heart health before starting potentially cardiotoxic treatments is crucial. We continue to monitor patients post-treatment, as side effects can appear years later. Despite these risks, heart damage from cancer treatment is quite rare. The majority of cardiology patients in cancer treatment had pre-existing heart conditions or developed unrelated heart issues.

Factors such as hypertension, diabetes, and high cholesterol also affect heart health. Symptoms of heart failure to watch for include chest pain, unusual shortness of breath, swelling in the legs, and difficulty lying flat due to shortness of breath. Prompt medical attention is advised if these symptoms are observed.

To minimise the risk of heart damage from cancer treatments, staying active, maintaining a healthy weight, and following a Mediterranean-style or mostly plant-based diet low in sugar are recommended. While most patients are unlikely to develop heart problems due to cancer treatments, these health practices offer significant benefits for overall well-being.

Author:Manuela Boyle
Tags:NewsCancerchemotherapy side effectsBlogsRecovery into Enduring Wellness


  • The Institute for Functional Medicine
  • Society for Integrative Oncology
  • Naturopaths and Herbalists Association of Australia
  • Australian Traditional-Medicine Society
  • British Naturopathic Association