How should we determine length of anticoagulation after proximal deep vein thrombosis of the lower limbs?

The current approach for deciding the duration of vitamin K antagonist (VKA) treatment after an episode of venous thrombo-embolism (VTE) is mainly based on the characteristic of the index event (3 months or longer in case of unknown/persistent risk factors, 3 months or less in case of removable causes). However, the length of anticoagulation should be tailored on the patient's risk for recurrent thrombosis as well as for bleeding, but such 'time for decision' is often unclear and the optimal duration of VKA remains debatable. The presence of persistent residual vein thrombosis and increased D-dimer levels after stopping therapy are predictors for recurrent deep vein thrombosis (DVT). Management strategies based on these parameters have been demonstrated to optimize the decision for VKA duration, as they establish the patient's intrinsic risk for recurrent events. This annotation discusses current practice and upcoming approaches regarding the length of VKA treatment after a first episode of DVT.