Time frame of the decisions. Initial management (yellow box) spans the first 1 to 3 weeks after diagnosis of a new vein thromboembolism and includes issues concerning whether the patient can be treated at home or requires admission to the hospital, use of thrombolytic therapy, whether an inferior vena cava filter needs to be placed, and initial anticoagulant therapy. Primary treatment (blue box) continues anticoagulant therapy for 3 to 6 months total and represents the minimal duration of treatment of the VTE. After completion of primary treatment, the next decision concerns whether anticoagulant therapy will be discontinued or whether it will be continued for secondary prevention (red box) of recurrent VTE. Typically, secondary prevention is continued indefinitely, although patients should be reevaluated on a regular basis to review the benefits and risks of continued anticoagulant therapy.