Surgery is generally recommended for atrial septal defects of 9mm, but comprehensive judgment is also needed. Because the defect is large at this time, the possibility of self-healing is generally small, and timely surgery is recommended; if the defect area is small, the patient’s symptoms are mostly not obvious, and the infant has the possibility of self-healing, it can be observed first. Many atrial septal defects will close on their own during childhood. If the defect does not close, and the atrial septal defect is small, and there are no clinical symptoms, treatment is generally not needed, and observation can be carried out first. However, if the atrial septal defect is 9mm, the possibility of self-healing is generally smaller, and surgical treatment is recommended, in addition to the choice of surgery based on the child’s overall condition and the specifics of the atrial septal defect. It is important to note that in adults with atrial septal defects, surgery to close the defect should be performed as soon as possible, provided that there is evidence of increased right ventricular volume loading on ultrasound. If you are found to have an atrial septal defect, it is recommended that you go to the hospital immediately and follow your doctor’s instructions for treatment.