Cardio-Oncology: Breast Cancer Treatment and Your Heart

HER2-Targeted Therapies

Signs and Symptoms


In most cases of cardiotoxicity from HER2-targeted therapies, a decline in heart function will be found during routine monitoring with the patient having no symptoms or vague symptoms, such as fatigue. In some cases, however, the decrease in heart function will be accompanied by symptoms of heart failure.

In heart failure, the heart isn’t pumping as well as it should, which leads to fluid buildup in the lungs and eventually in the legs. Patients may experience:

  • Shortness of breath, especially with exertion.
  • Swelling of the ankles, legs and sometimes abdomen.
  • Chest pressure or shortness of breath when lying flat. 
  • Waking up with severe shortness of breath. 
  • Rapid changes in weight. 
  • Heart palpitations.
  • Extreme fatigue.
  • Decreased appetite. 
  • Nausea. 

If you develop any of these symptoms, talk to your doctor at once. 

< HER2-Targeted Therapy Risks Exams and Tests >

Published: February 2018
Author: Roberta Florido, MD
Medical Reviewers: Debra Madden, BA; Karen Lisa Smith, MD, MPH

These modules were developed in collaboration with the Eastern Cooperative Group—American College of Radiology Imaging Network (ECOG-ACRIN) Cardiotoxicity Working Group and Patient Advocacy Group.

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