Venogram vs. Intravascular Ultrasound (IVUS) for Diagnosing Iliac Vein Obstruction

Study Overview
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Brief Summary
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The purpose of this study is to demonstrate that IVUS identifies more instances of significant iliac and common femoral vein outflow obstruction than multiplanar venography.No hypothesis testing is planned.

Official Title
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Prospective, Single-arm, Multi-center, Pilot Study of IVUS Imaging Used as an Adjunct to Multiplanar Venography During Iliac-common Femoral Vein Assessment for Possible Endovascular Intervention

Conditions
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Iliac Venous Compression

Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Subject must be > 18 and < 85 years of age Willing to participate in and able to understand, read and sign the informed consent document before the planned procedure CEAP clinical classification: C4, C5, or C6 (enrollment of C4 and C5 subjects will be capped at 50, such that at least 50 C6 subjects can be enrolled) On duplex ultrasound: patent common femoral vein, and patent deep femoral vein, and/or femoral vein of the study leg Undergoing iliofemoral and inferior vena caval venography with the intent to treat obstructive lesions Exclusion Criteria: Subject cannot or will not provide written informed consent Previous venous stent implantation involving the study leg or inferior vena cava Previous venovenous bypass surgery involving the study leg Known metal allergy precluding endovascular stent implantation Known reaction or sensitivity to iodinated contrast that cannot be managed with premedication Subjects who are pregnant (women of childbearing potential must have a negative pregnancy test within 7 days prior to enrollment Severe, untreated (and readily treatable) superficial venous reflux (great saphenous vein >7 mm in diameter, and/or small saphenous vein >4 mm in diameter) Acute deep venous thrombosis involving either leg Known history of chronic total occlusion of the common femoral vein of the study leg. Known history of thrombophilia (e.g., protein C or S deficiency, anti-thrombin III deficiency, presence of lupus anticoagulant, etc.) Venous compression caused by tumor encasement Venous outflow obstruction caused by tumor thrombus Life expectancy of less than 6 months Elevated baseline blood creatinine (value greater than the upper limit of the normal range) Any concurrent disease or condition that, in the opinion of the Investigator, would make the subject unsuitable for participation in the study; examples include but are not limited to the inability to lie supine for the index procedure (e.g., severe congestive heart failure), thrombocytopenia or other hematological disorders associated with an unacceptable risk of bleeding, implanted orthopedic hardware that precludes proper imaging, etc.

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 85 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 |
| --- | --- |
| Venography and IVUS imaging guiding treatment<br> | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| 100 patients with Clinical-Etiologic-Anatomic-Pathophysiologic (CEAP) classification C4-6 undergoing iliac and common femoral and venography with intention to treat venous outflow obstruction. | Primary Endpoints: Both venous IVUS and traditional venography will provide measurements of minimum and maximum diameter reduction due to iliofemoral venous obstruction/compression; cross-sectional area reduction will also be measured by IVUS, and calculated for venography (from min. and max. diameters, assuming elliptical cross-section6). The diameters and cross-sectional area are compared to adjacent reference vessel in order to calculate the degree of stenosis. The percentage of significant stenosis detected at various thresholds [e.g., 50%, 60%, 70%, 80%, for diameter reduction, and (separately) for area reduction] with each method will be compared in a pair-wise fashion. This will be done with descriptive statistics of the detection rates for each method, and the rate of discordance between the two. In addition to the binary outcome of significant stenosis, the numeric values for diameters and cross-sectional areas will be compared. | 6 month | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Iliac Vein, Common Femoral Vein, Iliac Compression, Venous outflow obstruction