Deep Vein Thrombosis of Lower Limb Clinical Trial
Official title:
Identification of the Optimal Duration of Anticoagulation in Patients With Deep Venous Thrombosis of the Lower Extremities With the Use of Residual Vein Thrombosis in Combination With D-Dimer
Prospective cohort study aimed at optimizing the duration of anticoagulant treatment in patients at their first episode of proximal deep venous thrombosis (DVT) of the lower extremities, whose pathogenesis is either unknown (idiopathic DVT) or associated with minimal risk factors for thrombosis, with the help of an algorithm which incorporates both ultrasonography and D-dimer information. All patients will be followed-up until 1) the achievement of a major end-point; 2) the date of lost to to followup; 3) the date of death; 4) the date of study stop. The purpose of this study is to demonstrate the safety of withholding anticoagulation from a subgroup of patients with proximal DVT whose veins have recanalized and present with a repeatedly negative D-dimer (at baseline, after 1 and 3 months). The approach will be deemed to be safe if the annual rate of recurrent VTE in patients who will have their anticoagulation discontinued is lower than 5%.
After giving informed consent, patients will receive an ultrasound investigation of the
proximal-vein system (common femoral vein at groin, popliteal vein up to its trifurcation):
- Patients with residual thrombosis (defined as a diameter of at least 4 mm in at least
one spot) will have their anticoagulation continued. A repeat ultrasound is scheduled
after 6, 12, 18, 24 and 36 months. In patients with persistently residual thrombosis
anticoagulation will not be discontinued, while those whose veins have recanalized will
have a decision making process based on the behaviour of D-dimer (see below).
- Patients whose veins have recanalized (either at the recruitment or later on) will
receive the D-dimer determination before discontinuing anticoagulation. In those with
negative D-dimer anticoagulation will be discontinued. These patients will have two
further determinations of D-dimer (after 1 and 3 months, respectively). While patients
with persistently negative D-dimer will no longer receive anticoagulation, those in
whom D-dimer becomes positive will have their anticoagulation resumed and no longer
discontinued.
- All patients will be followed up to completion of 4 years since recruitment. For the
purpose of this study each quantitative D-dimer is allowed. The criterion for D-dimer
interpretation will rely on the cut-off that is recommended by manufacturers for
diagnostic purposes.
D-dimer.For the purpose of this study each quantitative D-dimer is allowed. The criterion
for D-dimer interpretation will rely on the cut-off that is recommended by manufacturers for
diagnostic purposes.
Sample size 1000 years of observation without anticoagulation are required to demonstrate
(power 90%, type I error 0.05, two sided) that with this approach the annual rate of
recurrent VTE is lower than 5%. Approximately 600 patients with proximal DVT satisfying the
eligibility criteria are required to obtain 1000 years of observation without
anticoagulation.
;
Endpoint Classification: Safety/Efficacy Study, Intervention Model: Single Group Assignment, Masking: Open Label, Primary Purpose: Treatment
| Status | Clinical Trial | Phase | |
|---|---|---|---|
| Completed |
NCT00358735 -
Deep Vein Thrombosis (DVT) Prevention in Total Hip Arthroplasty: Continuous Enhanced Circulation Therapy (CECT) Versus Low Molecular Weight Heparin (LMWH)
|
N/A |