本研究旨在评估经左室压应变环（LVPSL）治疗乳腺癌患者化疗后左室（LV）心肌工作（MW）的变化。选择了50名接受包含蒽环类化疗的新诊断乳腺癌患者。在治疗前（T0），第二（T2）和第四（T4）个化疗周期以及化疗结束后3（P3 m）和6（P6 m）个月进行超声心动图检查。收集所需部位的标准动态图像。离线分析后，获得常规、全球心肌应变和全球MW参数，并计算LV三个级别的平均区域MW指数（RMWI）和区域MW效率（RMWE）。与T0和T2相比，T4、P0和P6 m的全球工作指数（GWI）、全球构造工作（GCW）、全球工作效率（GWE）和全球纵向应变（GLS）逐渐降低，全球浪费工作（GWW）逐渐增加。三个级别的LV的平均RMWI和RMWE呈逐渐下降趋势，与T0和T2相比，T4、P0和P6 m的GWI、GCW、GWE、平均RMWI、和RMWE（基底、中段和顶端）均与GLS呈负相关（r=-0.76，-0.66，-0.67，-0.76，-0.77，-0.66，-0.67，-0.59和-0.61），而GWW与GLS呈正相关（r=0.55）。 平均RMWI和RMWE是反映LV心肌毒性的有效参数，LVPSL在评估乳腺癌患者蒽环类药物治疗期间和随访中左室心肌工作（LVMW）的价值具有一定的参考价值。

This study aimed to evaluate the changes in the left ventricular (LV) myocardial work (MW) in breast cancer patients following chemotherapy by left ventricular pressure-strain loop (LVPSL).A total of 50 patients with newly breast cancer undergoing postoperative adjuvant chemotherapy containing anthracycline were selected. Echocardiography was performed before the treatment (T0), the second (T2) and fourth (T4) cycles of chemotherapy, and 3 (P3 m) and 6 (P6 m) months after the end of chemotherapy. The standard dynamic images of the required sections were collected. After off-line analysis, the routine, global myocardial strain, and global MW parameters were obtained, and the average regional MW index (RMWI) and regional MW efficiency (RMWE) at three levels of LV were calculated.Compared with those at T0 and T2, the global work index (GWI), global constructive work (GCW), global work efficiency (GWE), and global longitudinal strain (GLS) gradually decreased and global wasted work (GWW) gradually increased at T4, P0, and P6 m. The mean RMWI and RMWE of the three levels of LV exhibited a gradually decreasing trend at T4, P0, and P6 m compared with those at T0 and T2. The GWI, GCW, GWE, mean RMWI, and RMWE (basal, medial, and apical) were negatively correlated with the GLS (r = -0.76, -0.66, -0.67, -0.76, -0.77, -0.66, -0.67, -0.59, and -0.61, respectively), whereas the GWW was positively correlated with the GLS (r = 0.55).The mean RMWI and RMWE are effective parameters to reflect the cardiotoxicity of LV, and LVPSL has certain value in the evaluation of the left ventricular myocardial work (LVMW) during anthracycline treatment and follow-up in breast cancer patients.