Prolonged Anticoagulation After a First Episod of Idiopathic Proximal Deep Vein Thrombosis (PADIS TVP)

In a French multicenter double blind randomized controlled trial, the main objective is to demonstrate that, after 6 months of oral anticoagulation for a first episode of idiopathic proximal deep vein thrombosis, 18 months of warfarin therapy is associated with a lower cumulative risk of recurrent VTE and major bleeding in comparison with that on 18 months of placebo. The secondary objectives are: (1) to determine the risk of recurrent VTE after 6 months of warfarin therapy and the presence or the absence of residual lung scan perfusion defect and the persistence or not of elevated D-dimer test; and (2), to determine the impact of extended duration of anticoagulation on the risk of VTE after stopping anticoagulant therapy on a follow-up of 2 years.