The general public can know about myocardial infarction when it is mentioned in the society, but I am afraid that the level of knowledge about pulmonary embolism is very low, which was a serious fact in the past. Pulmonary embolism is divided into two types: acute and chronic. The time frame of acute pulmonary embolism is currently clinically inconclusive. Acute pulmonary embolism is actually not a “static” concept, but a dynamic and complex pathophysiological process. The clinical manifestations after embolism and the severity of the disease depend on the size and number of emboli, the interval between multiple emboli, the presence of other cardiopulmonary diseases, the differences in individual responses and the speed of thrombus dissolution, etc. All these aspects have an important influence on the pathogenesis. Therefore, the time frame and concept of acute versus chronic pulmonary embolism PTE is not well defined clinically, and the onset of symptoms within one month is generally referred to as acute pulmonary embolism. Deep vein thrombosis dislodges and obstructs the pulmonary artery to form pulmonary embolism, if not treated properly, the thrombus cannot be dissolved in time may gradually chronicize or even mechanize, in addition, the thrombus may repeatedly dislodge to the pulmonary artery will further aggravate this situation, and form severe pulmonary hypertension and right heart insufficiency, we call it chronic thromboembolic pulmonary hypertension, referred to as chronic pulmonary embolism. When chronic pulmonary embolism occurs, the pulmonary artery vascular tree is blocked, and the oxygen carried by the blood is reduced. The body hyperventilates in order to compensate, resulting in shortness of breath, which becomes more pronounced the more oxygen the body needs. As part of the artery is blocked, the right heart must intensify pumping. The right heart becomes larger and thicker due to the extra work done, and during exercise the right heart pumping needs to be intensified again, leading to vertigo and syncope when the compensatory capacity of the right heart is exceeded. If the heart is overloaded with pressure, heart failure can develop. In heart failure, blood stagnates in veins throughout the body, for example, leading to bloating, poor appetite, and swelling of the lower extremities. All these conditions suggest the occurrence of chronic pulmonary embolism. The chance of chronic pulmonary embolism increases significantly if it is not treated regularly.