Ancillary Study of the ULTREC Project

Study Overview
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Brief Summary
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The ULTREC research project is designed to assess the safety of a negative strategy relying on Colour Doppler Ultrasound (CDUS) for excluding the diagnosis of a new thrombosis. The ULTREC project does not take into account the validity of the CDUS positive criteria used to confirm the diagnosis of Deep Vein Thrombosis (DVT) recurrence. The risk of considering only the negative strategy is to ignore the possibility of having an improvement in sensitivity and negative predictive value at the expense of specificity and positive predictive value and therefore to increase the false positive rate leading to an overdiagnosis of recurrence and an overtreatment, and a potential bleeding risk. In the ULTREC-ANCILLARY study, the research will aim at assessing the validity of baseline CDUS positive criteria for the diagnosis of DVT recurrence. As there is no diagnostic standard to which the results could be compared, it is suggested to validate these criteria based on the evolution of the thrombosis on CDUS performed at D90±5. The hypothesis is that an unchanged appearance under anticoagulation would be in favor of sequelae and will invalidate the initial diagnosis (diagnostic failure)

Official Title
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Validation of Ultrasonic Positive Diagnosis Criteria of Ipsilateral Deep Vein Thrombosis Recurrence of the Lower Limbs Based on Thrombosis Evolution at a 3-month Follow-up Under Anticoagulation: The ULTREC Project Ancillary Study

Conditions
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Deep Vein Thrombosis

Intervention / Treatment
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* Other: Color Doppler Ultrasound


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Age ≥ 18 years Known history of objectively documented deep vein thrombosis of the lower limb (with or without pulmonary embolism) Out-patients referred for clinically suspected acute recurrent ipsilateral DVT of the lower limb Patients covered by social security or an equivalent regimen No objection to the use of the data Inclusion in the ULTREC study Exclusion Criteria: Known current pregnancy Any condition, which may prevent from performing the colour doppler ultrasound test Delay from onset of symptoms to inclusion of more than 10 days Therapeutic anticoagulation for more than 48 hours in the two days prior to consent to ULTREC Study Presence of clinical symptoms or signs of pulmonary embolism Life expectancy less than 3 months Patient unable to adhere to ULTREC protocol follow-up Participants under judicial protection or incapacity

Ages Eligible for Study
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Minimum Age: 18 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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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Patients included in the ULTREC study who had a recurrence of deep vein thrombosis<br>Patients who have a baseline CDUS diagnosis of recurrent DVT as identified in the ULTREC study. | Other: Color Doppler Ultrasound<br>* Comparison between D90±5 and baseline CDUS<br>* Other names: Diagnosis strategy;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Evolution of the thrombosis at D90±5 | Failure rate judged on the stable aspect of the thrombosis at D90±5 defined by the absence of change in the obstruction and the extent of the thrombosis and the absence of change in the venous diameter under compression (no increase or increase < 4 mm). Vein diameter is measured under compression by ultrasound in a cross-sectional view from the external wall to the external wall of the vein segment. | 90 days | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Validation of positive DVT criteria by comparison between D30±2 and baseline CDUS | Failure rate judged on the stable aspect of the thrombosis at D30±2 defined by the absence of change in the obstruction and the extent of the thrombosis and the absence of change in the venous diameter under compression (no increase or increase < 4 mm) | 30 days | 
| Clinical and Imaging characteristics | Comparison of clinical and CDUS imaging characteristics between day-0 and day-90 visits | 90 days | 
| Evolution during follow-up | Rate of worsening, stabilization and improvement (regression, normalization) Worsening is defined by : a transition from partial obstruction to complete occlusion of a vein segment, an increase ≥ 4 mm in vein diameter measurement or progression of thrombus to another vein segment. Stabilization is defined by : an unchanged pattern. Improvement (regression, normalization) is defined by : a transition from a complete occlusion to a partial obstruction or normalization of the vein segment. | 90 days | 
| Baseline characteristics for favorable outcome | Imaging and clinical characteristics of thrombus at Day-0 visit | 1 day | 
| Venous diameter | Evolution of venous diameter at day-90 as measured under compression by ultrasound in a cross-sectional view from the external wall to the external wall of the vein segment | 90 days | 
| Diagnosis of individual characteristics of DVT recurrence | Failure rate related to the baseline measurement of vein diameter and ULTREC diagnostic recurrence positivity criteria (defined as an occlusive thrombus or a partially obstructive thrombus without reflux, or a free-floating thrombus). | 90 days | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Deep vein thrombosis, Recurrence, Colour doppler ultrasound, Diagnostic strategy, Outcome