Atrial fibrillation (AF) increases the risk of stroke and arterial embolism and increases the mortality rate. Anticoagulants such as warfarin can significantly reduce stroke, but they also have many disadvantages, such as uncertain efficacy, susceptibility to food and drugs, narrow drug concentration window, increased risk of bleeding, and so on. Study found that 90% of blood clots in patients with simple atrial fibrillation originate from the left atrial appendage[1,2]。 Therefore, closing the left atrial appendage will significantly reduce the thrombosis of the left atrial appendage in patients with atrial fibrillation and reduce the risk of stroke in patients with atrial fibrillation.