Surgery for ventricular septal defects less than 3mm is not recommended for young children, and in children or adults, the need for immediate surgery is determined by the condition. Ventricular septal defects of 3mm are small septal defects, and according to clinical studies, these small septal defects do not cause significant symptoms of dyspnea, heart failure, or oxygen deprivation in the early stages. This phenomenon can be self-healed before the age of three, so surgery is not required. However, if the patient is older, surgery is needed immediately. If the patient does not heal spontaneously after the age of three, regular observation is required before a plan can be developed based on the condition of the defect. Early surgery is recommended if the defect increases in size, if there are symptoms such as fatigue, chest tightness, or if pneumonia develops after repeated exposure to colds and flu; if there is no discomfort, surgery is usually recommended after the age of five. If a ventricular septal defect is found, it is recommended that the patient consult a doctor in a timely manner, have regular checkups, and follow the doctor’s instructions to avoid deterioration of the condition.