Original article

Early left ventricular ejection fraction trajectories according to CTox risk score in breast cancer patients treated with anthracycline and/or trastuzumab therapy

Authors

• • Cynthia Margaretha
  • Department of Internal Medicine
  • Universitas Sumatera Utara View ROR record for Universitas Sumatera Utara. (opens in new tab)
• • Naomi Dalimunthe naomi.niari@usu.ac.id Email Naomi Dalimunthe. (compose email, opens in email app.) Naomi Dalimunthe ORCID profile. (opens in new tab)
  • Department of Internal Medicine, Division of Cardiovascular
  • Universitas Sumatera Utara View ROR record for Universitas Sumatera Utara. (opens in new tab)
• • Heny Syahrini Lubis
  • Department of Internal Medicine, Division of Haematology and Oncology
  • Universitas Sumatera Utara View ROR record for Universitas Sumatera Utara. (opens in new tab)
• • Taufik Sungkar
  • Department of Internal Medicine, Division of Gastroenterology and Hepatology
  • Universitas Sumatera Utara View ROR record for Universitas Sumatera Utara. (opens in new tab)
• • Melati Silvanni Nasution
  • Department of Internal Medicine, Division of Endocrine and Metabolic Disease
  • Universitas Sumatera Utara View ROR record for Universitas Sumatera Utara. (opens in new tab)

Abstract

Aim: To evaluate early within-patient changes in left ventricular ejection fraction (LVEF) and to describe these early LVEF trajectories according to CTox risk category

Methods: This retrospective observational cohort study included 100 breast cancer patients treated at Adam Malik Hospital, from January to December 2024. CTox score was calculated prior to therapy initiation. Echocardiography was performed before the third cycle and after the fourth cycle of anthracycline- or trastuzumab-based therapy. The primary endpoint was early within-patient change in LVEF. 

Results: Based on CTox classification, 53% of patients were categorized as low-to-moderate risk and 47% as high-to-very high risk. Mean LVEF decreased from 62.64 ± 7.80% to 59.95 ± 7.46%, with a mean change of −2.69 ± 9.01% (p = 0.004). Early LVEF change did not differ between risk groups (between-group difference 0.54%; 95% CI, −2.97 to 4.05; p = 0.766). CTox score was not associated with early LVEF change when modelled as a continuous variable (β = 0.55; p = 0.453) or after adjustment for treatment regimen (β = 0.92; p = 0.212). Treatment type was independently associated with early LVEF change (p = 0.026).

Conclusion: A modest early decline in LVEF was observed during initial therapy cycles. Early LVEF trajectory was not associated with CTox risk category but was influenced by treatment regimen. These findings should be interpreted as early imaging trajectory data rather than cardiotoxicity risk prediction.

Keywords: anthracyclines, cardiac function, drug-related side effects and adverse reactions, neoplasms, trastuzumab

How to Cite: Margaretha, C. , Dalimunthe, N. , Lubis, H. S. , Sungkar, T. & Nasution, M. S. (2026) “Early left ventricular ejection fraction trajectories according to CTox risk score in breast cancer patients treated with anthracycline and/or trastuzumab therapy”, Medicinski glasnik. 23(2). doi: https://doi.org/10.17392/medglas-2166-23-2