Echocardiographic Follow-Up in HER2 Positive and Negative Breast Cancer Patients: Is There a Sustained Decline in Left Ventricular Function Parameters Following Chemotherapy?

Background: Breast cancer, as the most common malignancy among females, is a great concern for global health. Early diagnosis and advanced chemotherapy regimens have improved patients’ survival, while increasing morbidities caused by chemotherapy in the long run. Chemotherapy regimens have caused a decrease in myocardial functional, which can be detected by echocardiography.

Objectives: The present study aimed to assess the decline curve in the left ventricular function parameters following chemotherapy and to compare the results among patients based on their Human Epidermal Growth Factor Receptor-2 (HER2) status.

Methods: This study was conducted on 427 consecutive female patients with breast cancer referred to the Cardio-Oncology Department of Rajaie Cardiovascular, Medical, and Research Center for pre-chemotherapy assessment between January 2019 and December 2020. The patients were divided into two groups based on the HER2 status. All the patients had at least one baseline (pre-chemotherapy) transthoracic echocardiography and were scheduled for four follow-up sessions: early post-anthracycline therapy and 3, 6, and 12 months following chemotherapy. Each echocardiography examination included the assessment of 2D Left Ventricular Ejection Fraction (LVEF), 3D LVEF, Global Longitudinal Strain (GLS), and Global Circumferential Strain (GCS). Linear mixed-effects models were utilized and the results were compared within and between the study groups. The R Project for Statistical Computing was used for data analysis.

Results: The results revealed significant changes in the means of 2D LVEF, 3D LVEF, GLS, and GCS during the 12 months of follow-up (t = -27.04, -37.15, -33.3, and -21.5, respectively; P < 0.001). Besides, the decline was more prominent in the HER2 positive patients (t = -19.86, -15.35, -10.8, and -9.6, respectively; P < 0.001).

Conclusions: The study results revealed a significant decline in the LV function parameters including 2D LVEF, 3D LVEF, GLS, and GCS following chemotherapy with anthracycline. This decline was more prominent in the HER2 positive patients who underwent Herceptin treatment. These results showed that the use of cardioprotective agents might lower the rate of decline in LV function parameters.