Patient: The patient had mitral valve dilatation surgery fifteen years ago, and a month ago she developed an irregular heart rate and dizziness. He was examined and said that he needed a valve replacement, what is the best valve to replace? Zhang Jinzhou, Cardiovascular Surgery Department, Xijing Hospital: Biologic and mechanical valves have their own advantages and disadvantages. Biologic valves do not require long-term oral anticoagulants, so they do not require regular review and have a high quality of life, but currently biologic valves face the possibility of secondary surgery, and the literature reports that biologic valves last up to 23 years. Mechanical valves require long-term oral anticoagulation and regular checkups to adjust the dosage of anticoagulants, which has a greater impact on life. Although mechanical valves can theoretically last a lifetime, they are prone to anticoagulation-related complications after surgery, such as cerebral hemorrhage and thrombosis, which threaten patients’ lives. The exact choice of valve depends on the patient’s own wishes.