RESUMO
INTRODUCTION: Although epirubicin has significantly improved outcome in breast cancer (BC) patients, it is responsible for myocardial dysfunction that affects patients' quality of life. The use of 2D global longitudinal strain (GLS) has been reported to detect early myocardial dysfunction. The aim of this study was to evaluate how GLS changes can predict cardiotoxicity. METHODS: We conducted a prospective study from March 2018 to March 2020 on 66 patients with no cardiovascular risk factors, who presented with BC and received epirubicin. We measured left ventricular ejection fraction (LVEF) and GLS before chemotherapy, at three months (T3), and at 12 months (T12) from the last epirubicin infusion. Chemotherapy-Related-Cardiac-Dysfunction (CTRCD) was defined as a decrease of 10% in LVEF to a value below 53% according to ASE and EACI 2014 expert consensus. RESULTS: The mean age at diagnosis was 47 ± 9 years old. At baseline, median LVEF was 70% and median GLS was -21%. Shortly after chemotherapy completion, two patients presented with symptomatic heart failure while asymptomatic CTRCD was revealed in three other patients at T12. Three months after the last epirubicin infusion, median LVEF was 65%, median GLS was -19%, and median GLS variation was 5%. However, in patients who presented with subsequent CTRCD, median GLS at T3 was -16% and median GLS variation was 19% (p=0.002 and p < 0.001, respectively, when compared to patients who did not develop cardiotoxicity). Persistent GLS decrease at T3 was an independent predictor of CTRCD at T12. Age and left-sided thoracic irradiation did not increase the risk of cardiotoxicity in our study while the cumulative dose of epirubicin significantly affected cardiologic findings (p=0.001). CONCLUSION: This was the first North African study that assesses the value of measuring GLS to early detect cardiotoxicity. Patients whose GLS remained decreased after 3 months from anthracyclines-base chemotherapy had an increased risk for developing subsequent CTRCD. Further studies with larger sample size are warranted to identify the best cardioprotective molecules to be initiated in these patients before LVEF declines.