Clinical manifestations: There are many types of congenital heart disease, and their clinical manifestations depend mainly on the size and complexity of the malformation. Complex and severe malformations can show serious symptoms soon after birth and even be life-threatening. It should be noted that some simple malformations such as ventricular septal defect and patent ductus arteriosus can have no obvious symptoms in the early stage, but the disease can still potentially develop and worsen, requiring timely diagnosis and treatment to avoid losing the opportunity for surgery. The main symptoms are: 1. frequent colds, recurrent respiratory infections, and susceptibility to pneumonia. 2.Poor growth, wasting, and excessive sweating. 3.Impotent sucking during breastfeeding, difficulty in feeding, or infant refuses to eat, choking and coughing, and usually shortness of breath. 4.Children complain of easy fatigue and poor physical strength. 5.Blue lips and nails or bruising after crying or activity, pestle-shaped fingers and toes (nail bed bulging like a hammer). 6.Like squatting, fainting, hemoptysis. 7.Heart murmur is found on auscultation.