Once they learn that their child has congenital heart disease, a large number of parents are very anxious and feel that the sky is falling. Every parent does not want their child to undergo risky treatments such as surgery or interventions. Some parents may have heard that some congenital heart diseases may heal on their own, so they also want to know whether their child’s congenital heart disease can heal on its own and whether they can avoid the pain and risk of interventional or surgical treatment. As far as the accumulated clinical experience is concerned, there is no possibility of self-healing for complex congenital heart disease. Some simple congenital heart diseases can heal on their own: I. Atrial septal defect Atrial septal defect is one of the most common congenital heart diseases, and there are five types: foramen ovale, secondary foramen, coronary sinus, venous sinus and primary foramen. Clinical data show that oval foramen type atrial septal defects and small secondary foramen type atrial septal defects have the potential to heal spontaneously. The self-healing rate of secondary septal defects and foramen ovale septal defects less than 5 mm in diameter is 80%. Some septal defects of 5-8 mm can heal within 3 weeks of age. Coronary sinus, venous sinus, and foramen ovale septal defects do not close on their own and must be treated surgically. In general, secondary foraminal septal defects of 8mm or less can be treated without urgency and the decision can be made after the child reaches the age of 3. Secondary foraminal septal defects of 8mm or more, coronary sinus, venous sinus and primary foraminal septal defects generally do not heal on their own and can be treated surgically with good results around the age of 1 year. Ventricular septal defect is the most common precordial disease, accounting for about 30% of all precordial diseases. According to the location, ventricular septal defect can be divided into five types: perimembranous type (also known as supraventricular crest inferior type), funnel type (also known as supraventricular crest superior type and inferior stem type), myocardial type, atrioventricular access type (also known as post-septal valve type), and mixed type. Depending on the size, infantile ventricular septal defects are classified as small defects, medium defects, and large defects. In small defects, the diameter of the defect opening is less than 12.5 px or smaller, in medium defects, the large diameter of the defect is between 0.6 and 22.5 px, and in large defects, the diameter of the defect hole is greater than 25 px. Some ventricular septal defects can heal on their own, and the probability of self-healing of ventricular septal defects is related to the location and size of the defect. Small and medium-sized (especially small) perimembranous and muscular ventricular septal defects have the possibility of self-healing, and the smaller the ventricular septal defect, the greater the possibility of self-healing. Self-healing of ventricular septal defects often occurs within 2 years of age, especially within 1 year of age. In the literature, the self-healing rate of small muscular ventricular septal defects ranges from 37.9% to 93% within 1 week of age; for small to medium-sized perimembranous ventricular septal defects, the self-healing rate ranges from 4.7% to 35% within 1 week of age. Mechanisms of self-healing ventricular septal defects include: 1. Covered closure: Mostly occurs in perimembranous defects, where the posterior tricuspid valve leaflet and part of the septal leaflet or tendon tissue adhere to the edge of the defect and close with it covered. It is likely to occur in the presence of high right ventricular pressure. The mitral valve leaflets may also cover and close their adjacent defects, especially if complicated by endocarditis. 2, Invasive closure: Myocardial defects are reduced by the development of septal muscles, which, together with vortex fibrosis at the edges, form a fibrous membrane or fibrous plug to occlude the defect. 3, Reduction and filling closure: the defect is closed by endocardial hyperplasia and fibrosis, and the defect can also be occluded by superfluous organisms formed by infective endocarditis. In general, the rule of self-healing of ventricular septal defect is that the closure rate of small defect is high, and the closure rate of large defect is low; the closure rate of myocardial and perimembranous defect is high, but the sub-stem type defect cannot close by itself; the closure rate is high within 2 years old, and the closure rate is low above 2 years old; it is difficult to close by itself in combined pulmonary hypertension. For medium-large ventricular septal defect and sub-stem ventricular septal defect that cannot heal by themselves, children are prone to recurrent respiratory infections, heart failure, feeding difficulties, excessive sweating, shortness of breath, pulmonary vascular lesions, pulmonary hypertension, valvular regurgitation and other secondary damages. Third, the ductus arteriosus is a tube connected between the descending part of the aortic arch and the pulmonary artery. During fetal life, the fetal circulatory system depends on its existence, but it should close naturally after birth. If the ductus arteriosus fails to close, a passage between the aorta and the pulmonary artery remains, called a patent ductus arteriosus. Arteriovenous ductus arteriosus is also one of the common precordial diseases. Arteriovenous ductus arteriosus can be broadly classified into 5 types: tubular, funnel, dumbbell, window, and aneurysmal. Tubular, funnel and dumbbell ductus arteriosus with a diameter of less than 4 mm have the possibility of self-healing. The incidence of ductus arteriosus in preterm infants is significantly higher than in term newborns, and the incidence is higher in low birth weight newborns than in those of normal weight. In term newborns, under normal circumstances, about 50% of the ductus arteriosus closes spontaneously 24 hours after birth, 90% close 48 hours after birth, and all ductus arteriosus closes within 72 hours. However, there is a potential for reopening within 7-8 days after birth. If the ductus arteriosus remains unclosed after 1 week of life, there is no possibility of automatic closure. In preterm infants, the time to autoclosure of the ductus arteriosus is significantly longer. Typically, 60% of arterial ducts close within 3 days of birth and 72%-75% close within 3 months of birth. Although it is thought that automatic closure is possible up to 2 years of age, it is generally believed that it is very rare for a ductus arteriosus to close spontaneously after 3 months of life if it has not closed. If a child develops shortness of breath, excessive sweating, weakness, feeding difficulties, recurrent pneumonia, and growth retardation, interventional or surgical treatment should be promptly performed.