D-dimer to Select Patients With First Unprovoked Venous Thromboembolism Who Can Have Anticoagulants Stopped at 3 Months

Inclusion criteria

• Be >= 18 years of age
• Have had ONE episode of unprovoked proximal DVT and/or PE
• Have completed 3 uninterrupted months of warfarin therapy (target INR of 2.0-3.0)

Exclusion criteria

• Another indication for long-term anticoagulation (e.g., atrial fibrillation)
• A high risk of bleeding as evidenced by any of the following:

• Age greater than 75 years
• Previous episode of major bleeding where the cause was not effectively treated
• Known chronic thrombocytopenia with a platelet count of less than 120,000 x 10^9 /L
• Known chronic renal impairment with a creatinine of more than 150 mumols /litre (1.7 mg/dl)
• Known chronic liver disease with a total bilirubin of more than 25 mumols /litre (1.5 mg/dl)
• Active peptic ulcer disease
• Poor compliance with, or control of, anticoagulant therapy during initial treatment
• Requires dual antiplatelet therapy (e.g. aspirin and clopidogrel)
• A vena caval filter
• Has had D-dimer testing performed within 2 months of potential enrollment other than for evaluation of suspected recurrent VTE that was not confirmed
• Has a life expectancy less than 5 years
• Is unable to attend follow-up visits because of geographic inaccessibility
• Is participating in a competing clinical investigation