Pulmonary embolism is a multidisciplinary disease that can occur in surgery, orthopedics, oncology, obstetrics and gynecology, and cardiology, and has previously received little attention, with high rates of underdiagnosis and misdiagnosis. The incidence rate in Western countries is 1.0 per 1,000, and pulmonary embolism has become the 3rd cause of death in the United States, with 200,000 new cases per year. In China, there is no accurate epidemiological information yet. In recent years, with the improvement of diagnostic awareness and examination technology, the number of diagnosed cases is increasing year by year, which improves the cure rate of pulmonary embolism and reduces the disability rate and death rate. Is pulmonary embolism and deep vein thrombosis the same disease? Pulmonary thromboembolism accounts for more than 90% of pulmonary embolism, in addition to fat embolism caused by fracture, amniotic fluid embolism caused by postpartum, air embolism and so on. Pulmonary thromboembolism is the obstruction of pulmonary artery or its branches by thrombus from venous system or right heart, which causes pulmonary circulation and respiratory dysfunction. When the obstruction of pulmonary artery is extensive, it can cause acute pulmonary hypertension, right heart enlargement, and the manifestation of acute pulmonary heart disease and acute respiratory failure. The thrombus of pulmonary thromboembolism mainly comes from deep vein thrombosis. When the thrombus is dislodged, it will block the pulmonary artery with blood circulation and cause pulmonary embolism, so the two are two manifestations of the same disease in different parts and stages. Who are prone to pulmonary embolism? Pulmonary thromboembolism and deep vein thrombosis have common risk factors, which include primary and secondary factors, the former is related to family inheritance, the latter is related to surgery, fracture, trauma, malignant tumor, heart disease, oral contraceptive pills and other factors. The thrombus causing pulmonary thromboembolism can come from the inferior vena cava, superior vena cava or right heart cavity, and most of them come from the inferior deep veins, especially the double lower limb deep veins. When the deep vein thrombus dislodges and obstructs the pulmonary artery, it causes a series of clinical symptoms, and the severity of the disease depends on the size of the thrombus. When a large embolus obstructs the pulmonary artery and its branches, it causes pulmonary hypertension through mechanical obstruction and neurohumoral and hypoxemia, resulting in acute pulmonary heart disease, which can lead to right heart insufficiency and blood pressure drop and endanger life. And non-massive pulmonary embolism sometimes only shows a small amount of hemoptysis and chest pain, but it also needs timely treatment. Third, what are the clinical manifestations of thrombosis? The following clinical manifestations should be alerted to the possibility of pulmonary embolism: 1. unexplained dyspnea and shortness of breath; 2. pleuritic chest pain or angina-like chest pain; 3. sudden syncope; 4. irritability, panic or frequent death; 5. cough, hemoptysis: often small amount of hemoptysis; 6. palpitations; 7. new asymmetric swelling of both lower extremities; the above symptoms may not necessarily occur in the same patient at the same time, but when some of them appear, there are risk factors. When some of these symptoms appear and there are risk factors, you should seek medical attention in time to avoid delaying the disease and losing the chance to save the patient. Of course, if a large pulmonary embolism occurs, the mortality rate is very high, and some patients even have too late to seek medical attention and die suddenly. Therefore, we hope that the high-risk groups in the society will raise their awareness of this disease and seek medical treatment promptly when clinical symptoms appear. D. What is the prognosis of pulmonary embolism? The prognosis of pulmonary embolism depends on the severity of the disease and the level of clinician’s understanding of the disease. The prognosis is good with early diagnosis and treatment, but the mortality rate of large pulmonary embolism is high even if it develops in the hospital. In addition, during thrombolysis and anticoagulation treatment, complications such as blood in urine, subcutaneous and intracranial hemorrhage should be guarded against. Since pulmonary embolism is a multidisciplinary disease, the level of awareness of the disease among clinicians of various disciplines is improving, which greatly reduces the rate of missed diagnosis and mortality. Since pulmonary embolism is clinically nonspecific, diagnosis of pulmonary embolism requires caution. In addition to the corresponding symptoms, signs and high-risk factors, plasma D–dimer, blood gas analysis, electrocardiogram, X-ray examination should be done, and the final confirmation of the diagnosis also relies on intensive spiral CT or radionuclide pulmonary ventilation/perfusion scan and pulmonary arteriography. Once pulmonary thromboembolism is established, different treatment options can be chosen depending on the severity of the disease. During the thrombolytic anticoagulation treatment, it is necessary to strictly obey the doctor’s prescription, and stopping the medication without authorization will easily lead to another pulmonary embolism and endanger the life. V. Is there any similarity between pulmonary embolism and myocardial infarction? There are similarities between the two, the former is pulmonary embolism and the latter is coronary artery infarction, both have different degrees of chest pain. However, there are also differences in that the lungs have two sets of blood supply: once the pulmonary artery is blocked, there are still bronchial arteries to supply blood flow, so the time window for thrombolysis in pulmonary embolism is within 14 days, and in some cases, thrombolysis can be performed within 30 days. In contrast, the coronary artery has only one set of blood supply, and the collateral circulation cannot be formed in a short period of time, so the time window for thrombolysis is different. Of course, regardless of pulmonary or cardiac infarction, early diagnosis and early treatment can improve the prognosis. Our hospital is a member of the National Pulmonary Embolism Collaborative Group and has advanced multi-row spiral CT, color Doppler cardiovascular ultrasound, MRI, etc. as well as well-trained professional technicians. If you find suspicious cases of pulmonary embolism around you, remind them to seek medical attention in time to avoid delaying the disease and losing the time for rescue and treatment. We hope that the society will raise the awareness of this disease and strengthen the popularization and propaganda of self-care knowledge.