RESUMO
BACKGROUND: Chemotherapy with fluorouracil, adriamycin, and cyclophosphamide (FAC) regimen in breast cancer patients may cause myocardial injury and necrosis, thereby attenuating global and regional longitudinal strain (GLS and RLS). It is unclear whether the first chemotherapy cycle would cause GLS and RLS reduction and which segment would be most affected by the chemotherapy. The purpose of the study was to investigate the effect of the first chemotherapy cycle on GLS and RLS reduction. METHODS: This was a prospective single-center cohort study of patients with breast cancer who underwent the first chemotherapy cycle with a FAC regiment. The GLS and RLS were measured using speckle tracking echocardiography and left ventricular ejection fraction (LVEF) measured with Simpson's biplane. The echocardiography was performed before and 3 weeks after the first chemotherapy cycle. We compared the value of GLS, RLS, and LVEF before and after chemotherapy using paired t-test analysis. RESULTS: Thirty-six breast cancer patients were enrolled in the study. The GLS and RLS were reduced significantly at 3 weeks compared to baseline. The RLS of the basal anteroseptal, basal anterolateral, mid anterolateral, mid inferolateral, and all apical segments declined significantly from baseline. The largest RLS decline was detected in the apicoanterior segment. The post-chemotherapy GLS but not LVEF was significantly lower than that before treatment. CONCLUSION: The GLS and RLS of patients who underwent first cycle chemotherapy with FAC declined significantly than that before treatment, especially at the apicoanterior segment. LVEF was not altered after first cycle chemotherapy.