A double-blind randomized trial was conducted to research a hypercoagulable state rebound after abrupt versus gradual withdrawal of acenocoumarol, 20 patients were included: 10 in the abrupt withdrawal group (AW) and 10 in the gradual withdrawal group (GW). Between days 1 and 15,F1 + 2 was higher in group AW (P < 0.002). A significant increase of D-dimer with time was found (P < 0.001) without difference between the two groups, tPA and PAI-1 levels remained stable throughout without difference between the two groups. No rebound phenomenon was observed. Four thrombotic recurrences were observed: group AW: 1, group GW: 3 (P = 0.29). There is neither clinical nor biological support for a gradual anticoagulation withdrawal.