Compared with traditional cardiac surgery, minimally invasive cardiac surgery has the following advantages: I. Small incision The length of minimally invasive small incision is only 6-7 cm, and the incision is located in a relatively hidden part of the chest, which is more beneficial to female patients. II. Less bleeding Small surgical trauma, less bleeding, no need for blood transfusion, reducing the risk of blood transfusion. Fast recovery No need for median chest opening, stable thorax, fast getting out of bed and fast recovery. IV. Less cost Short hospitalization time, less cost, affordable for patients.