The medical term PTE is an acronym for pulmonary thromboembolism, which is a type of pulmonary embolism. And pulmonary embolism refers to pulmonary artery embolism, which is a series of symptoms caused by various emboli blocking the pulmonary artery or branches of the pulmonary artery, including pulmonary thromboembolism, fat embolism, amniotic fluid embolism, air embolism, etc., among which pulmonary thromboembolism is the most common. Previously, pulmonary thromboembolism was thought to be a rare disease, but with the improvement of modern diagnostic technology has changed this concept. In developed countries in Europe and America, the incidence of pulmonary thromboembolism is second only to ischemic heart disease, that is, coronary heart disease and hypertension, and the mortality rate is relatively high. If left untreated, the mortality rate of pulmonary thromboembolism can reach 30%. The embolus of pulmonary thromboembolism mainly comes from the formation of thrombus in the deep veins of the lower limbs. The thrombus from the veins of the lower limbs reaches the pulmonary artery with the blood flow, causing the obstruction of the pulmonary artery, resulting in the inability to exchange oxygen effectively, and the human body will be deprived of oxygen, resulting in symptoms of chest tightness, shortness of breath, difficulty in breathing, chest pain and even hemoptysis. Therefore, in terms of pathogenesis, pulmonary thromboembolism is very similar to myocardial infarction, one is blocking the pulmonary artery and the other is blocking the coronary artery. Therefore, pulmonary thromboembolism is often colloquially called “pulmonary infarction”.