What caused the small hole in the left atrium? What should we do?

Hello, children under one year old. At first, he was diagnosed with pneumonia in the hospital. I'm in the hospital now. But later, he underwent a heart examination. The doctor said there was a small hole in the heart and a small hole in the left atrium. According to your description, the child is considered as a congenital heart disease, but if it is a small atrial defect, it is possible to heal itself. Theoretically, it's not that serious. Early pregnancy (5-8 weeks) is the most important period for fetal heart development. Some internal or external factors affect the normal development of fetal heart, which is an important cause of congenital heart disease. At present, the technology of treating congenital heart disease is mature and the effect is good. I hope my answer is helpful to you, and I wish you health and happiness.