This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Medicine
The treatment of choice in recurrent venous thrombosis leading to pulmonary embolism despite intensive anticoagulation is: 
Select and explain. 
A. Fibrinolysis treatment with tissue plasminogen activator, B. Pulmonary embolectomy, C. Pulmonary thromboendaerectomy, D. Inferior vena caval filters
D: Inferior vena caval filters
Answer: D: Inferior vena caval filters 
Explanation: The two indications for inseion of an IVC filter are (1) active bleeding that precludes anticoagulation and (2) recurrent venous thrombosis despite intensive anticoagulation. Ref: Harrisons Principles of Internal Medicine, 18th Edition, Page 2176.