Atrial septal defect (ASD) is a common congenital heart disease, and its incidence accounts for about 20% of congenital heart diseases. Previously, open-chest repair with direct visualization under extracorporeal circulation was the only treatment method, but this method is very traumatic to the body and not easily accepted by patients. Interventional approach to atrial defect occlusion overcomes these disadvantages, but the indications are limited to central atrial defects, and the occluder is easy to fall off. Transthoracic open window minimally invasive atrial septal defect occlusion is a new interventional ASD treatment method developed in recent years, which combines the advantages of surgery and interventional treatment and expands the indications for minimally invasive treatment of ASD, especially for the occlusion of large atrial defects and atrial defects in children. Since 2002, our department was the first to perform minimally invasive small incision chest wall perforation atrial septal defect closure in South China, and the follow-up results are satisfactory. The procedure is described as follows: 1. A small incision of about 3 cm in length is made in the chest wall at the beginning of the operation, and a plugging device is placed from the right atrium. 2. The plugging device is released under the guidance of esophageal ultrasound during the operation and the plugging effect is observed. 3. The appearance of the plugging device is used during the operation. 4. The appearance of the incision after the operation is compared with the traditional surgical incision. (3) small surgical incision, in line with the cosmetic requirements; (4) less surgical bleeding, no blood transfusion; (5) short operation time, the average intracardiac operation time of about 10 minutes, the total operation time of less than 1 hour, less patient pain, fast recovery; (6) simple and convenient operation, safe and reliable, less cost, compared with transvenous catheter intervention atrial defect closure, about 20% cheaper; (7) short hospitalization time, the day of surgery (7) Short hospitalization time, can live on the ground on the same day of surgery.