The arterial duct is a pathway through which blood from the maternal placenta is delivered to the fetus. This pathway usually closes at birth, and in most cases, it successfully closes within three months. If it remains open after one year, it can be diagnosed as a patent ductus arteriosus. The shapes of the arterial duct include funnel-shaped, tubular, and window-type. Regardless of the type, if it does not cause serious cardiac complications, it can be addressed with interventional treatments or surgical procedures, making it a relatively non-severe condition. However, if the patent ductus arteriosus remains open for a long time, leading to severe pulmonary arterial hypertension and even left-to-right shunts causing serious cardiac dysfunction, it is considered severe. Therefore, the shape of the patent ductus arteriosus does not have diagnostic significance regarding the severity of the condition. Rather, the severity is assessed based on the patient's symptoms, evaluation of cardiac function through echocardiography, and the condition of pulmonary artery pressure. In the early stages, most cases of patent ductus arteriosus are not very serious and can be resolved through treatment.