Limitations
There are still many limitations to our research. Firstly, the sample size of our study was not large enough, and the follow-up time was not long enough to track the clinical event. But we follow up time was more frequent could detect the early cardiac change in time. Secondly, 3D echocardiography requires a clear and complete endocardial surface, which requires high image quality, and the images we choose were relatively clear and complete. In patients with left mastectomy, the early data cannot be improved one week after the operation due to incision and hematoma, and the late acoustic transparency is worse than that of patients with right mastectomy. Therefore, the number of patients with left mastectomy is small, and the selection of patients’ samples was relatively limited.