Rivaroxaban for the Prevention of Deep Vein Thrombosis in Patients With Left Iliac Vein Compression - The PLICTS Study

Study Overview
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Brief Summary
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The purpose of this study is to evaluate the efficacy and safety of rivaroxaban for the prevention of deep vein thrombosis in patients with left iliac vein compression treated with stent implantation.

Detailed Description
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Left Iliac Vein Compression Syndrome (LIVCS) is a disease of iliac vein stenosis/occlusion caused by chronic friction and compression of the left iliac vein by the right common iliac artery and lumbar vertebra. It is also called Cockett syndrome or May-Thurner syndrome. Recently, left iliac vein balloon dilatation with stent implantation have been used to treat patients with LIVCS, and have achieved good results. However, no matter the iliac vein stenosis or occlusion, interventional therapy can directly cause local trauma and intimal injury, which is a clear inducement of local thrombosis. Therefore, high intensity anticoagulation therapy is still needed to prevent secondary thrombosis in stent after left iliac vein balloon dilatation with stent implantation. At present, the postoperative anticoagulation regimen of these patients is early heparin anticoagulant therapy, and later warfarin anticoagulant therapy. However, due to the narrow therapeutic window of the drug, patients need to adjust the dosage according to coagulation function under the guidance of doctors. Rivaroxaban can simplify treatment, and is safe. Previous studies have shown that rivaroxaban is effective in preventing deep venous thrombosis after orthopaedic surgery. Rivaroxaban has also been shown to be safe and effective in anticoagulation therapy for patients with deep venous thrombosis and pulmonary embolism. However, Rivaroxaban lacks sufficient clinical data for adjuvant anticoagulation therapy after balloon dilatation with stent implantation. Therefore, this study should be carried out to provide the basis for LIVCS treatment guidelines and explore the clinical indications of rivaroxaban.

Official Title
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An Efficacy and Safety Study of Rivaroxaban for the Prevention of Deep Vein Thrombosis in Patients With Left Iliac Vein Compression Treated With Stent Implantation (PLICTS)：A Prospective Randomized Controlled Trial

Conditions
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May-Thurner Syndrome

Intervention / Treatment
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* Drug: Rivaroxaban
* Drug: Warfarin
* Drug: Nadroparin


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients with thrombotic left iliac vein compression syndrome who underwent left iliac vein stent implantation Exclusion Criteria: Age < 18 years or age > 75 years With history of pelvic surgery, left iliac vein trauma and pelvic radiotherapy With obvious contraindications for anticoagulation therapy Allergic to iodine contrast agents in the past With concomitant diseases that need high-intensity anticoagulation, and the anticoagulation intensity is clearly higher than that of the patients with iliac vein therapy alone Active bleeding or potential bleeding risk Pregnant or breastfeeding women With pelvic tumors causing compression of left iliac vein, With chronic venous insufficiency of lower extremities caused by K-T syndrome With malignant tumors and life expectancy < 1 year Taking cytochrome P450 3A4(CYP-450 3A4) inhibitors or inducers

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 75 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: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Rivaroxaban<br>Participants will receive rivaroxaban 15mg twice daily for three weeks, then 20mg oral once daily after operation. | Drug: Rivaroxaban<br>* Dose: 15mg twice daily for three weeks, then 20mg once daily until six months after the operation. Application: oral<br>* Other names: Xarelto;|
| Active Comparator: Warfarin/Nadroparin<br>Participants will receive nadroparin 1mg/kg twice daily (subcutaneous), plus warfarin 3mg oral once daily for 5 days after the operation, later warfarin(oral) at individually titrated doses(0.75mg to 18mg) to achieve a target international normalized ratio (INR) of 2.0 to 3.0, once daily until 6 months. | Drug: Warfarin<br>* Dose: 3mg for 5 days after the operation, later 0.75mg to 18mg depending on INR (2.0-3.0) until 6 months Duration: 6 months Frequency: once daily Application: oral<br>* Other names: coumadin;Drug: Nadroparin<br>* Dose: 1mg/kg Duration: 5 days after the operation Frequency: twice daily Application: subcutaneous<br>* Other names: Fraxiparin;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| stent occlusion rate | Stent occlusion is defined as DS > 50% for each modality with no procedure performed on the treated segment | 2 year after operation | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Quality of Life Change Scale Survey Results | Quality of life will be assessed by MOS item short-form health survey scale (SF-36). SF-36 includes eight subscales: physical functioning (PF, 10 items), role limitations due to physical health problems (RL-P, 4 items), bodily pain (BP, 2 items), general health (GH, 5 items), vitality (V, 4 items), social functioning (SF, 2 items), role limitations due to emotional problems (RL-E, 3 items) and mental health (MH, 5 items). The vitality sub-score assesses energy and fatigue, and ranges from 0 (worst) - 100 (best). | 1, 3, 6, 12, 18 and 24 months after operation | 
| All cause mortality | Percentage of participants with all deaths | 1, 3, 6, 12, 18 and 24 months after operation | 
| anticoagulation raleted mortality | Percentage of participants with anticoagulation raleted deaths | 1, 3, 6, 12, 18 and 24 months after operation | 
| Proportion of participants with stent displacement/fracture | Events will be assessed based on computed tomography (CT) or X ray | 1, 3, 6, 12, 18 and 24 months after operation | 
| Proportion of participants with hemorrhage | Including hemorrhagic stroke, gastrointestinal bleeding, hematuria, mucocutaneous hemorrhage and other visceral bleeding | 1, 3, 6, 12, 18 and 24 months after operation | 
| Proportion of participants with other vascular events | All vascular events (ST segment elevation myocardial infarction, non ST segment elevation myocardial infarction, acute coronary syndrome, unstable angina, ischemic stroke, transient ischemic attack, pulmonary embolism, non-central nervous system systemic embolism or vascular death) will be assessed based results/films/images of confirmatory testing, and/or case summaries. | 1, 3, 6, 12, 18 and 24 months after operation | 
| Proportion of participants with thrombosis |  | 1, 3, 6, 12, 18 and 24 months after operation | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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May-Thurner Syndrome, warfarin, rivaroxaban, stent implantation