A 3mm ventricular defect is not a lifelong condition that does not require surgery. Generally, a 3mm ventricular septal defect has the potential to heal by the age of three, but if it does not heal by the age of three, and there is a lung infection or other symptoms of heart failure, the patient needs to be actively pursued with surgical treatment. Patients with 3mm ventricular septal defect belong to small defects, the defect does not exceed 1/3 of the diameter of the aorta, the chance of complications is small, and some of the patients will not be affected for life, and children before the age of three have a certain chance of healing from 3mm ventricular septal defects, and generally do not need surgical treatment. However, patients with obvious lung infection and heart failure need to consult a doctor immediately, and according to the situation of the operation. However, for patients with obvious signs of lung infection and heart failure, immediate medical attention is needed, and surgery will be performed according to the situation. Patients with ventricular septal defects need to have regular checkups, observation and follow-up, and should consult a doctor in time to complete the relevant examinations, and under the guidance of the doctor, actively treat the condition to avoid deterioration.