Quantitative assessment of changes in left ventricular myocardial work and energy loss in HER2-positive breast cancer patients undergoing combination therapy with chemotherapy and targeted treatment using pressure-strain loop and vector flow mapping

The GWI of the HER2⁺ BC patients was significantly lower at both T2 and T4, the GLS, GCW, and GWE were decreased at T4, while the GWW was increased at T4. The SEL and AEL of the HER2⁺ BC patients were significantly increased at T2 and T4 during the AC period, and the SEL and AEL were increased during the RF, IVS, and RE periods at T4. The energy loss (EL) and PSL metrics reflect the left ventricular wall mechanics and hemodynamics of HER2⁺ BC patients undergoing combined therapy.