More than 15% of breast cancer survivors have cardiac dysfunction by 15 years, researchers reported in study findings published in the Journal of Clinical Oncology. Additionally, they identified certain risk factors that are associated with the development of cardiac dysfunction after receiving cardiotoxic cancer treatments. 

The study comprised 829 breast cancer survivors and 2,808 echocardiograms, which were performed every two years. Researchers defined cardiac dysfunction as left ventricular ejection fraction less than 50% following cardiotoxic therapies. Participants were included in the study if they received anthracyclines (38%), trastuzumab/pertuzumab (16%), anthracyclines and trastuzumab/pertuzumab (6%), or radiation alone (38%).

Researchers found a cardiac dysfunction incidence of 1.8% at two years and 15.3% at 15 years. Besides cardiotoxic cancer therapies, analysis revealed several other risk factors for cardiac dysfunction: non-Hispanic Black race, selective estrogen receptor modulators, and hypertension. Additionally, researchers found that increased risk of early-onset cardiac dysfunction was associated with anthracyclines and trastuzumab/pertuzumab, whereas late onset was associated with radiation and anthracyclines.

Because cardiac dysfunction is the most common cause of death among long-term breast cancer survivors, the authors highlighted the need for long-term surveillance, evaluation of risk mitigation strategies for patients treated with cardiotoxic therapies, and development of surveillance guidelines for these patients.

However, “limited information regarding long-term risks of cardiac dysfunction after cardiotoxic therapy has precluded development of surveillance guidelines for breast cancer survivors,” they wrote. They said that their findings may contribute to enhanced surveillance strategies and guidelines for cardioprotection in patients being treated for breast cancer.

Cardio-oncology is an emerging subspecialty, and better prevention strategies and treatments are being developed as more studies come to light. Learn more about cardiac issues in oncology through the ONS resources in the sidebar.