D-dimer testing to determine the duration of anticoagulation therapy.

The optimal duration of oral anticoagulation in patients with idiopathic venous thromboembolism is uncertain. Testing of D-dimer levels may play a role in the assessment of the need for prolonged anticoagulation. We performed D-dimer testing 1 month after the discontinuation of anticoagulation in patients with a first unprovoked proximal deep-vein thrombosis or pulmonary embolism who had received a vitamin K antagonist for at least 3 months. Patients with a normal D-dimer level did not resume anticoagulation, whereas those with an abnormal D-dimer level were randomly assigned either to resume or to discontinue treatment. The study outcome was the composite of recurrent venous thromboembolism and major bleeding during an average follow-up of 1.4 years. The D-dimer assay was abnormal in 223 of 608 patients (36.7%). A total of 18 events occurred among the 120 patients who stopped anticoagulation (15.0%), as compared with 3 events among the 103 patients who resumed anticoagulation (2.9%), for an adjusted hazard ratio of 4.26 (95% confidence interval [CI], 1.23 to 14.6; P=0.02). Thromboembolism recurred in 24 of 385 patients with a normal D-dimer level (6.2%). Among patients who stopped anticoagulation, the adjusted hazard ratio for recurrent thromboembolism among those with an abnormal D-dimer level, as compared with those with a normal D-dimer level, was 2.27 (95% CI, 1.15 to 4.46; P=0.02). Patients with an abnormal D-dimer level 1 month after the discontinuation of anticoagulation have a significant incidence of recurrent venous thromboembolism, which is reduced by the resumption of anticoagulation. The optimal course of anticoagulation in patients with a normal D-dimer level has not been clearly established. (ClinicalTrials.gov number, NCT00264277 [ClinicalTrials.gov].).

Palareti G ，Cosmi B ，Legnani C ，Tosetto A ，Brusi C ，Iorio A ，Pengo V ，Ghirarduzzi A ，Pattacini C ，Testa S ，Lensing AW ，Tripodi A ，PROLONG Investigators ... -  《-》

Residual venous obstruction, alone and in combination with D-dimer, as a risk factor for recurrence after anticoagulation withdrawal following a first idiopathic deep vein thrombosis in the prolong study.

This study aims to assess the predictive value of residual venous obstruction (RVO) for recurrent venous thrombo-embolism (VTE) in a study using D-dimer to predict outcome. This is a multicentre randomised open-label study. Patients with a first episode of idiopathic VTE were enrolled on the day of anticoagulation discontinuation when RVO was determined by compression ultrasonography in those with proximal deep vein thrombosis (DVT) of the lower limbs. D-dimer was measured after 1 month. Patients with normal D-dimer did not resume anticoagulation while patients with abnormal D-dimer were randomised to resume anticoagulation or not. The primary outcome measure was recurrent VTE over an 18-month follow-up. A total of 490 DVT patients were analysed (after excluding 19 for different reasons and 118 for isolated pulmonary embolism (PE)). Recurrent DVT occurred in 19% (19/99) of patients with abnormal D-dimer who did not resume anticoagulation and 10% (31/310) in subjects with normal D-dimer (adjusted hazard ratio: 2.1; p = 0.02). Recurrences were similar in subjects either with (11%, 17/151) or without RVO (13%, 32/246). Recurrent DVT rates were also similar for normal D-dimer, with or without RVO, and for abnormal D-dimer, with or without RVO. Elevated D-dimer at 1 month after anticoagulation withdrawal is a risk factor for recurrence, while RVO at the time of anticoagulation withdrawal is not.

Cosmi B ，Legnani C ，Iorio A ，Pengo V ，Ghirarduzzi A ，Testa S ，Poli D ，Tripodi A ，Palareti G ，PROLONG Investigators (on behalf of FCSA, Italian Federation of Anticoagulation Clinics) ... -  《-》

Residual vein thrombosis and serial D-dimer for the long-term management of patients with deep venous thrombosis.

The optimal long-term strategy for preventing recurrent venous thromboembolism (VTE) in patients with deep-vein thrombosis (DVT) is uncertain. In 620 consecutive outpatients with a first proximal DVT who had completed at least three months of anticoagulation (unprovoked in 483, associated with minor risk factors in 137), the ultrasound presence of residual vein thrombosis (RVT) was assessed and defined as an incompressibility of at least 4mm. In 517 patients without RVT and with negative D-dimer, anticoagulation was stopped and D-dimer was repeated after one and three months. Anticoagulation was resumed in 63 of the 72 patients in whom D-dimer reverted to positivity. During a mean follow-up of three years, recurrent VTE developed in 40 (7.7%) of the 517 patients, leading to an annual rate of 3.6% (95% CI, 2.6 to 4.9): 4.1% (95% CI, 2.9 to 5.7) in individuals with unprovoked DVT, and 2.2% (95% CI, 1.1 to 4.5) in those with DVT associated with minor risk factors. Of the 233 males with unprovoked DVT, 17 (7.3%) developed events in the first year of follow-up. Major bleeding complications occurred in 8 patients while on anticoagulation, leading to an annual rate of 1.2% (95% CI, 0.6 to 2.4). Discontinuing anticoagulation in patients with a first episode of proximal DVT based on the assessment of RVT and serial D-dimer leads to an overall annual rate of recurrent VTE lower than 5.0%, which is the rate deemed as acceptable by the Subcommittee on Control of Anticoagulation of the ISTH. However, in males with unprovoked DVT there is room for further improving the long-term strategy of VTE prevention. (ClinicalTrials.gov number, NCT01285661).

Prandoni P ，Vedovetto V ，Ciammaichella M ，Bucherini E ，Corradini S ，Enea I ，Cosmi B ，Mumoli N ，Visonà A ，Barillari G ，Bova C ，Quintavalla R ，Zanatta N ，Pedrini S ，Villalta S ，Camporese G ，Testa S ，Parisi R ，Becattini C ，Cuppini S ，Pengo V ，Palareti G ，Morgagni Investigators ... -  《-》

D-dimer testing to determine the duration of anticoagulant therapy.

Palareti G ，Cosmi B ，Legnani C 《-》

D-dimer levels in combination with residual venous obstruction and the risk of recurrence after anticoagulation withdrawal for a first idiopathic deep vein thrombosis.

Cosmi B ，Legnani C ，Cini M ，Guazzaloca G ，Palareti G ... -  《THROMBOSIS AND HAEMOSTASIS》