Prophylactic vs Therapeutic Anticoagulation in Symptomatic Isolated Distal Deep Vein Thrombosis

Study Overview
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Brief Summary
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The efficacy and safety of anticoagulant treatment is not established for patients with acute symptomatic isolated distal deep vein thrombosis (IDDVT). The latest Antithrombotic Therapy for VTE Disease Guideline suggested using the same anticoagulation as for patients with acute proximal DVT in patients with acute IDDVT. However, a single-center retrospective cohort study found therapeutic anticoagulation was associated with an increase risk of bleeding. Thus, this study aimed to assess the short-term risk of recurrent venous thrombotic events and bleeding events in patients with a first acute symptomatic IDDVT of the leg treated with prophylactic or therapeutic anticoagulant therapy with rivaroxaban.

Official Title
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Prophylactic vs Therapeutic Anticoagulation in Symptomatic Isolated Distal Deep Vein Thrombosis (IDENT): a Prospective, Multicenter, Single-blind, Randomized Controlled Trial

Conditions
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Venous Thrombosis

Intervention / Treatment
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* Drug: Rivaroxaban


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients aged 18-90 Outpatients with a first, acute (within 2 weeks), symptomatic, objectively confirmed isolated distal DVT Compliance to the scheduled follow up plan Ability and willing to participate and sign the informed consent. Exclusion Criteria: Any absolute contraindication to anticoagulant treatment Pregnancy or breast-feeding Systolic pressure > 180 mmHg or diastolic pressure > 100 mmHg Platelet count < 100 × 10⁹ /L Serum creatinine > 180 mmol/L or creatinine clearance ≤30 ml/min Liver disease associated with coagulopathy and high risk of bleeding Clinically suspected or confirmed pulmonary embolism Ipsilateral or contralateral proximal DVT Any indication for long-term anticoagulation Enrolled in another clinical trial simultaneously Life expectancy < 6 months

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 90 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Triple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Prophylactic Anticoagulation<br>Rivaroxaban 10 mg od for 3 months | Drug: Rivaroxaban<br>* Rivaroxaban 20 mg or 10 mg for 3 months<br>|
| Active Comparator: Therapeutic Anticoagulation<br>Rivaroxaban 20 mg od for 3 months | Drug: Rivaroxaban<br>* Rivaroxaban 20 mg or 10 mg for 3 months<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Radiographically confirmed recurrent venous thromboembolism | Recurrent venous thromboembolism includes proximal extension of isolated distal DVT, new contralateral proximal DVT and pulmonary embolism. | 6 months | 
| Major or clinically relevant non-major bleeding events | Major bleeding events are defined according to the International Society on Thrombosis and Haemostasis criteria. Clinically relevant non-major bleeding events refer to which do not meet the mentioned criteria of major bleeding but need at least an unscheduled in-person consultant. | 3 months | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Individual component of primary outcomes (e.g. proximal extension, major bleeding) | Individual component of primary outcomes, including proximal extension of isolated distal DVT, new contralateral proximal DVT, new pulmonary embolism, major bleeding events, clinically relevant non-major bleeding events. | 6 months | 
| Residual vein occlusion |  | 6 months | 
| Post-thrombotic syndrome |  | 6 months | 
| All-cause death |  | 6 months |