Chronic Venous Thrombosis: Relief with Adjunctive Catheter-Directed Therapy (C-TRACT)

C-TRACT Overview

C-TRACT (Chronic Venous Thrombosis: Relief with Adjunctive Catheter-Directed Therapy) is a multicenter, randomized trial led by Suresh Vedantham, MD, FSIR, of the Mallinckrodt Institute of Radiology, Washington University in St. Louis. It is funded by the National Heart, Lung and Blood Institute (NHLBI) within the National Institutes of Health (NIH). The study goal is to determine if the use of image-guided endovascular therapy (EVT) is an effective strategy to reduce the severity of post-thrombotic syndrome (PTS) and improve quality of life (QOL) in patients with established disabling iliac-obstructive post-thrombotic syndrome (DIO-PTS).   

The study is planning to enroll approximately 374 subjects at 20–40 clinical centers. All subjects will be asked to return for follow-up visits at 2, 4, 6, 12, 18, and 24 months post-randomization. Patient eligibility can be found in the protocol synopsis

SIR Foundation encourages SIR members to participate in this important effort to support evidence-based IR care by serving as site investigators or by referring patients to study sites.  

<p>More information about C-TRACT can be found on the <a href="">study's website</a>.</p>

More information about C-TRACT can be found on the study's website.

Get involved

Clinical centers

C-TRACT is planning to recruit between 20–40 clinical centers, which are selected based on site selection criteria. Interested sites are required to complete and submit the C-TRACT Study Site Questionnaire




Health provider referral tool

C-TRACT will enroll approximately 374 subjects. To reach this enrollment goal, an innovative mobile application was developed to refer potential patients to participating sites. The C-TRACT Referral Tool app is designed to help physicians submit patient referrals securely and conveniently. The C-TRACT referral tool app can be downloaded to your mobile device.

Referral Tool App



To find a list of publications related to this study, please visit the Washington University School of Medicine in St. Louis' scientific articles on New Image-Guided Treatments that Target Blood Clots.



Recent news

  • As of October 2021, C-TRACT has enrolled 119 subjects and has 29 active clinical centers. Participating sites are encouraged to continue enrolling subjects.
  • During SIR's 2021 Annual Meeting, Dr. Suresh Vedantham presented on the status of evolving venous disease therapies during "Venous Thromboembolism and Deep Venous Disease: The State of Evidence and its Impact on Treatment Strategies." An article of this presentation is highlighted in the spring 2021 issue of IR Quarterly.
  • Dr. Vedanatham discusses the enrollment criteria of the C-TRACT Trial in the 2021 spring issue of IR Quarterly.
  • Kush R. Desai, MD, FSIR, discussed the C-TRACT trial and the future of deep vein care in the summer 2020 issue of IR Quarterly. 
  • Dr. Vedantham discussed the C-TRACT trail and its potential for IR in the spring 2020 issue of IR Quarterly.
  • Dr. Vedantham and Mary Constantino, MD, FSIR, talk about the clinical importance of C-TRACT in The Kinked Wire Podcast.


Contact information

If you have any questions about SIR Foundation's involvement in C-TRACT, please contact the Director of Research and Grants.