Chronic Venous Thrombosis: Relief With Adjunctive Catheter-Directed Therapy (The C-TRACT Trial)

Study Overview
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Brief Summary
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The purpose of this study is to determine if the use of image-guided, endovascular therapy (EVT) is an effective strategy with which to reduce Post Thrombotic Syndrome (PTS) disease severity and improve quality of life in patients with established disabling iliac-obstructive post thrombotic syndrome (DIO-PTS).

Detailed Description
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The rationale for performing the C-TRACT Trial is based upon: the debilitating life impact of DIO-PTS upon patients, as cited in the U.S. Surgeon General's 2008 Call to Action on DVT (95); the inability of existing therapies to prevent or alleviate most cases of DIO-PTS; the role of iliac vein obstruction and saphenous reflux in causing the severe manifestations of DIO-PTS; the ability of stent placement and endovenous ablation to eliminate obstruction and reflux, respectively, to reduce PTS severity, and to improve QOL in preliminary studies; the risks, costs, and uncertainties of this novel but invasive strategy; the lack of consensus on whether EVT should be used for DIO-PTS; the motivation of our established investigator team to answer this critical clinical question. We will determine if EVT should be routinely used to treat DIO-PTS. If so, this finding will fundamentally change DIO-PTS practice towards more frequent use of EVT. If EVT proves ineffective or unsafe, this finding will reduce or eliminate the use of potentially risky and expensive procedures. 374 subjects with established DIO-PTS will be randomized in a 1:1 ratio to either EVT or No-EVT treatment groups. All participants will receive standard PTS therapy. Subjects will be enrolled over approximately 36 months in 20-40 U.S. Clinical Centers, and followed for 24 months. The study will take approximately 6 years to complete.

Official Title
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Chronic Venous Thrombosis: Relief With Adjunctive Catheter-Directed Therapy - The C-TRACT Trial

Conditions
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Deep Vein Thrombosis, Venous Stasis, Venous Insufficiency, Venous Leg Ulcer, Venous Reflux, Post Thrombotic Syndrome

Intervention / Treatment
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* Device: Stents


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Subjects must meet BOTH of these Criteria Disabling (moderate-to-severe) PTS, defined by a) presence of chronic venous disease > or = 3 months duration in a leg with history of DVT, as determined by the site principal investigator or a physician co-investigator; and b) substantial limitation of daily activities or work capacity due to venous symptoms or an open venous ulcer, per the same investigator. Ipsilateral iliac vein obstruction documented within 12 months prior to screening by either: Occlusion or >50% or = 50% stenosis of the iliac vein on venogram, CT venogram, MR venogram, or intravascular ultrasound (IVUS) or Air plethysmography showing deep venous obstruction of the ipsilateral leg (reduced venous outflow fraction), and ultrasound showing echogenic material in the ipsilateral iliac vein and non-phasic continuous Doppler flow in the ipsilateral common femoral vein (CFV) in the presence of normal phasic Doppler flow in the contralateral CFV. Exclusion Criteria: Subjects meeting any of these criteria will be excluded. Age less than 18 years Acute ipsilateral proximal DVT episode within the last 3 months, or acute contralateral DVT for which thrombolytic therapy is planned Lack of suitable inflow into the ipsilateral common femoral vein per the treating physician Previous stent placement in the infrarenal IVC or ipsilateral iliac or common femoral vein Absence of PTS of at least moderate severity Chronic arterial limb ischemia (ankle-brachial index < 0.5 within the previous 1 month) in the ipsilateral leg (if peripheral arterial disease is present or suspected, an ankle-brachial index should be obtained and documented) Presence of open venous ulcer > 50 cm2 area, suspicion for active ulcer infection, or visualization of bone or tendon within the ulcer in the ipsilateral leg Inability to tolerate endovascular procedure due to acute illness, or general health Severe allergy to iodinated contrast refractory to steroid premedication Known allergy to stent or catheter components Hemoglobin < 8.0 g/dl, uncorrectable INR > 3.05, or platelet count < 75,000/ml Severe renal impairment (on chronic dialysis or estimated GFR < 30 ml/min) Disseminated intravascular coagulation or other major bleeding diathesis Pregnancy (positive pregnancy test) Life-expectancy < 6 months or chronically non-ambulatory for reasons other than PTS Inability to provide informed consent or to comply with study assessments Note - patients who initially meet an exclusion criterion can have eligibility re-evaluated on a subsequent occasion.

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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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Interventional Model Description: This is an NIH-funded, Phase III, multicenter, randomized, open-label, assessor-blinded, parallel two-arm, controlled clinical trial.
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Endovascular Therapy - Intervention<br>All subjects (EVT and No-EVT Arms) will receive optimal PTS care. At each Clinical Center, this will be supervised by a physician experienced in managing PTS. Subjects randomized to EVT will receive the following: imaging-guided iliac vein stent placement, and endovenous ablation of refluxing saphenous vein(s), if the patient has truncal reflux and is still symptomatic. optimal PTS therapy: medical and compression, lifestyle interventions and venous ulcer care | Device: Stents<br>* US-guided puncture of vein, fluoroscopic monitoring of catheter/guidewire manipulations, baseline venogram of CFV through infrarenal IVC. Iliac vein should be pre-dilated to at least 12 mm. Bare, self-expanding stents made of elgiloy or nitinol legally marketed in the US for any indication and that are at least 12 mm in diameter should be used to recanalize the entire diseased segment of vein. The use of devices > 14 mm is highly recommended for the iliac vein and dilated to at least 14 mm, unless compelling patient factors dictates dilatation to a smaller diameter. Balloon angioplasty of inflow veins. After successful iliac vein recanalization, patients who continue to be symptomatic beyond 2 weeks follow-up and who have valvular reflux in GSV, accessory GSV, anterolateral thigh circumflex, and/or SSV should be offered endovenous ablation. Any FDA-approved method may be used including radiofrequency or laser ablation, sclerotherapy or pharmacomechanical ablation.<br>|
| No Intervention: Non-Endovascular Therapy - Control<br>All subjects will receive optimal PTS care as noted above. | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| PTS Severity | 374 patients with moderate to severe post thrombotic syndrome (PTS) and iliac vein obstruction will receive optimal PTS therapy. 50% of those patients will also receive endovenous therapy; modified antithrombotic therapy, including anti-platelet agent, iliac vein stenting, and endovenous ablation of refluxing saphenous veins if indicated. At 6 months post-randomization, venous clinical severity scores (VCSS) will be obtained and PTS severity will be evaluated. | over 6 months follow-up | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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deep vein thrombosis, superficial venous reflux, blood clot, post thrombotic syndrome, iliac vein obstruction