Ventricular septal defects of 5mm usually grow back, and some patients may not require surgical treatment and may grow back on their own. Ventricular septal defect is a congenital heart disease caused by an abnormality in the septum of the left and right ventricles during the fifth to seventh weeks of embryonic development, resulting in a septal defect in the corresponding area. Ventricular septal defect can exist alone or in combination with other cardiac malformations, and is usually classified as mild, moderate or severe. Patients with septal defects of 5 mm may have no obvious symptoms and can usually grow back on their own at this time, and regular observation and ultrasound examination of the heart are sufficient to look for abnormal blood flow and changes in the septal defect. If the ventricular septal defect 5mm heals completely during observation, surgery is not required. If the ventricular septal defect 5mm gradually increases, or if there is a clinically significant left-to-right shunt, a gradual increase in left ventricular load, pulmonary hypertension and significant clinical symptoms, surgery is required in a timely manner, and it usually grows back after surgery. Patients with ventricular septal defect 5mm can usually rest more, exercise less and maintain a good mood. If the effect of self-repair is not good, surgery can be performed in time to avoid complications such as infective endocarditis and congestive heart failure.