What causes pulmonary thrombosis

Pulmonary thrombosis is a common problem among cardiovascular and pulmonary vascular diseases. It causes great harm to patients, so it is important to understand the cause. Patients with heart disease, combined myocardial infarction or atrial fibrillation, heart failure and malignant tumors are prone to pulmonary thrombosis. Blood stasis and obese people who are bedridden for a long time may also develop this disease.

(A) Source of thrombus: Pulmonary thromboembolism is often caused by the migration of thrombus from the deep venous system of the lower extremities. It can also originate from thrombosis at the site of long-term indwelling catheters in the pelvic veins, renal veins, hepatic veins, and subclavian veins or superior vena cava. Sometimes non-thrombotic substances such as fat particles, amniotic fluid, air, tumor cell clusters, etc. can also cause it. According to domestic reports, about 30% of the pillars come from the right ventricle, especially when heart disease patients have myocardial infarction, atrial fibrillation, and heart failure, they are prone to pulmonary thromboembolism and 5-year death (ischemia and necrosis of lung tissue after pulmonary thromboembolism) caused by mural thrombus.

(II) Underlying diseases Pulmonary thromboembolism often occurs in patients with underlying diseases. Scholars in my country reported that heart disease was the most common cause (40%), followed by malignant tumors (including leukemia) (35%), thrombophlebitis accounted for 13%, infectious diseases 15%, pregnancy 4%, fractures 2%, and cirrhosis 1%. Other underlying diseases and causes include burns, kidney transplantation, artificial pneumoperitoneum, extracorporeal circulation and tibia cell anemia.

(III) Inducing factors Blood stasis, venous injury, and hypercoagulable state are factors that promote DVT.

1. Blood stasis Blood stasis is prone to occur in conditions such as long-term bed rest, obesity, heart failure, varicose veins and pregnancy.

2. Venous injury: Venous injury is often caused by surgery, trauma and burns. Especially after major surgeries such as pelvic and abdominal malignant tumor resection and larger orthopedic surgeries on the lower limbs, lower limb venous thrombosis and pulmonary thromboembolism are more likely to occur.

3. Hypercoagulable state Certain coagulation and fibrosis system abnormalities can easily cause venous thrombosis and pulmonary thromboembolism. Such as deficiency of antithrombin, protein C, protein S and certain components of the fibrinolytic system.