The Concurrent Use of Aromatase Inhibitors and Radiotherapy Induces Echocardiographic Changes in Patients with Breast Cancer

Aim: Adjuvant radiotherapy (RT) for left-sided breast cancer has a negative impact on cardiac health. The concurrent use of aromatase inhibitors (AIs) during RT was found to increase the anticancer efficacy of radiation in preclinical models. We evaluated whether the acute effects of RT on cardiac functions are augmented by the concurrent use of AIs. Patients and Methods: Sixty patients with early-stage left-sided breast cancer underwent a 2D echocardiography, electrocardiogram and cardiac biomarker measurements before and after adjuvant breast RT. Data were analyzed in two groups according to AI use. Results: We observed a significant (p<0.05) decrease in right ventricular systolic function during RT in tricuspid annular plane systolic excursion (TAPSE). TAPSE decreased by 3.0 mm [95% confidence interval (CI)=1.9-4.1 mm] in the AI group and 1.4 mm (95% CI=0.3-2.4 mm) in the non-AI group. In addition, left ventricular diastolic function decreased among patients using AI, as the mitral inflow E-wave decreased 5.8 cm/s (95% CI=1.8-9.7 ends) (p=0.006). Conclusion: The concurrent use of AI during RT for left-sided breast cancer led to a more pronounced change on right ventricular systolic function and left ventricular diastolic functions compared to RT alone.