Severe pulmonary hypertension progressing to Eisenmenger syndrome is a late stage of congenital heart disease, where the chance of surgery has been lost and the prognosis is poor and serious. Eisenmenger syndrome, or Eisenmenger-syndrome, also known as Eisenmenger syndrome depending on the phonetic translation, is a group of congenital heart disease that persists and pulmonary hypertension continues to progress resulting in. For example, congenital ventricular septal defects and arterial ductus arteriosus, because the left heart pressure is higher than that of the right heart, there will be a left-to-right shunt of blood flow and a gradual increase in the pressure of the pulmonary arteries, which produces pulmonary hypertension. Severe pulmonary hypertension is diagnosed on the basis of symptoms, a mean pulmonary artery pressure of >45 mmHg measured by right heart catheterization, or other examination findings. As pulmonary hypertension progresses, the original left-to-right shunt becomes a right-to-left shunt when the right heart pressure is higher than that of the left heart, and cyanosis, fatigue, dizziness, and symptoms of right heart failure occur. The right heart failure and respiratory failure of Eisenmenger syndrome are fatal, and the only effective treatment is combined heart-lung transplantation or lung transplantation with simultaneous repair of the heart, and some patients have even lost the chance of surgery, with a poor prognosis. It is recommended that patients with severe pulmonary hypertension progressing to Eisenmenger syndrome should seek timely medical attention and actively follow medical advice.