What are the risk factors for trastuzumab-induced cardiotoxicity?

Trastuzumab is a targeted breast cancer drug that can sometimes weaken the heart. Doctors call this trastuzumab-induced cardiotoxicity, or TIC. It usually shows up as a drop in left ventricular ejection fraction (LVEF), which is a measure of how much blood the heart pumps out with each beat, and less often as heart failure ¹⁰. Knowing who is at higher risk helps doctors watch those patients more closely. The strongest single risk factor is previous treatment with anthracyclines, a different class of chemotherapy drugs ⁹. Beyond that, common heart and metabolic conditions also raise the risk ¹⁰¹¹.

What the research says

A 2021 review of clinical risk factors found that cardiovascular disease risk factors, advanced age, and prior anthracycline treatment all make TIC more likely. Among these, anthracycline exposure stands out as the most significant risk factor ⁹. That review also notes that cardiac biomarkers like troponins and pro-BNP, plus echocardiograms before and during trastuzumab treatment, may help catch TIC early ⁹.

What to ask your doctor

• Ask whether you have received anthracyclines before, since that is the strongest risk factor for trastuzumab-related heart problems ⁹.
• Ask how your other heart risks (blood pressure, diabetes, smoking, family history of heart disease) might affect your risk ¹⁰¹¹.
• Ask whether you should have an echocardiogram or cardiac biomarker tests before and during trastuzumab treatment ⁹.
• Ask if a referral to a cardio-oncology specialist would be helpful for your situation ⁹.
• Ask whether any heart-protective medications might be right for you, and discuss the pros and cons with your care team ⁹.