Effect of Anthracycline Chemotherapy on Cardiac Toxicity and Evaluation of Two-Dimensional Speckle Tracking Imaging in Breast Cancer

The main objective of this study is to investigate the cardiac toxicity of anthracycline chemotherapy in patients with breast cancer and the significance of two-dimensional speckle tracking imaging technology. In this study, 83 patients with breast cancer were selected and divided into two groups. The control group was treated with paclitaxel for 4 w, and the study group was treated with epirubicin (anthracycline) for 4 w and paclitaxel for 4 w. The treatment course was 4 cycles. The changes of peak strain dispersion, global longitudinal strain and left ventricular ejection fraction of patients were examined by two- dimensional speckle tracking imaging technique. The left atrial diameter, left ventricular end diastolic diameter, left ventricular end systolic diameter, early to late mitral inflow velocity, early diastolic mitral annular velocity, the ratio velocity of early diastolic mitral inflow velocity to early diastolic annular, the changes of myocardial enzymes and N-terminal pro-B-type natriuretic peptide were observed. Before and after chemotherapy, there was no difference in the values of left atrial diameter, left ventricular end diastolic diameter, left ventricular end systolic diameter, early to late mitral inflow velocity and the ratio velocity of early diastolic mitral inflow velocity to early diastolic annular, myocardial enzymes and N-terminal pro-B-type natriuretic peptide (p>0.05). Before chemotherapy, there was no difference in the values of left ventricular ejection fraction, global longitudinal strain and peak strain dispersion (p>0.05). After chemotherapy, the values of global longitudinal strain, global longitudinal strain-A3C, A2C and peak strain dispersion in the study group were lower than those in the control group (p<0.05), while the values of global longitudinal strain- A4C were not significantly different (p>0.05). Breast cancer patients treated with anthracyclines accompanied by targeted drug chemotherapy have obvious toxicity to left ventricular function and two-dimensional speckle tracking imaging can detect these changes more sensitively than conventional cardiac ultrasound.