Chemotherapy-associated cardiotoxicity in women with breast cancer: assessment of left atrial strain by transthoracic echocardiography

Introduction Breast cancer is one of the most prevalent malignant neoplasms and cardiotoxicity induced by treatment with anthracyclines and trastuzumab is a major complication. Transthoracic echocardiography (TTE) is considered the gold-standard method for assessing cardiac function, with left ventricular ejection fraction (LVEF) and global longitudinal strain (GLS) being the main parameters used for early detection of cardiotoxicity. Left atrial (LA) strain represents the myocardial deformation of this structure and is assessed based on three main parameters, among which peak atrial longitudinal strain (PALS) stands out for best reflecting global LA function. Purpose To evaluate left atrial strain by TTE as a predictor of cardiotoxicity at different stages of treatment with anthracyclines and trastuzumab in women with breast cancer. Methods This was a retrospective, quantitative, descriptive, and correlational study. A total of 51 women with breast cancer were included through a non-probabilistic sampling method, all of whom underwent chemotherapy with anthracyclines and adjuvant therapy with trastuzumab. Serial echocardiographic monitoring of systolic and diastolic function parameters was performed, including the assessment of global longitudinal deformation and two-dimensional left atrial deformation, at four time points: pre-treatment (baseline TTE), first evaluation during treatment (TTE 2), second evaluation during treatment (TTE 3), and post-treatment (final TTE). Cardiac dysfunction related to oncological therapy was defined as a decrease in LVEF to < 50% and/or a relative reduction in GLS of > 15%, according to the 2022 consensus document of the European Society of Cardiology (ESC). Study variables: peak E-wave velocity, peak A-wave velocity, E/A ratio, septal e′ velocity, lateral e′ velocity, average E/e′ ratio, LA volume index, peak tricuspid regurgitation velocity, GLS, LVEF, and PALS - analysed using EchoPAC™ software (version 206). Results The mean follow-up time between baseline TTE and final TTE was 17 months, with a standard deviation of ± 4.61 months. Cardiotoxicity was identified in 9 women, in whom early functional changes were observed, with significant reductions in septal and lateral e′ velocities at all analysed time points. Systolic function showed significant differences between groups at all time points, both in LVEF and GLS (p < 0.001), demonstrating progressive contractile dysfunction, whereas PALS showed significant changes only at TTE 2 (p < 0.001), suggesting early but non-sustained atrial dysfunction. Conclusion GLS and LVEF were the most sensitive echocardiographic parameters for differentiating between groups with and without cardiotoxicity, showing consistent changes throughout the study. Septal and lateral e′ velocities allowed identification of diastolic function alterations from intermediate stages onward, while PALS demonstrated discriminative capacity at an early point.