C-TRACT Evaluates Endovascular Therapy to Treat Postthrombotic Syndrome After DVT 

April 13, 2026—The Society of Interventional Radiology (SIR) announced results from the C-TRACT study, which is investigating the treatment of postthrombotic syndrome (PTS) after deep vein thrombosis (DVT).

The study is sponsored by the National Institutes of Health with additional support from the SIR Foundation. It was co-led by Washington University School of Medicine in St. Louis, Missouri, and McMaster University in Hamilton, Canada. The study leadership included investigators from multiple specialties, including interventional radiology, noted SIR.

The C-TRACT findings were presented at the SIR 2026 annual scientific meeting and simultaneously published by Principal Investigator Suresh Vedantham, MD, et al in The New England Journal of Medicine.

According to SIR, C-TRACT is a randomized, multicenter trial comparing two treatment strategies for PTS. Investigators enrolled 225 patients with moderate to severe PTS at 29 institutions.

The patients were randomly assigned either to the active group that received endovascular therapy (iliac-vein stent placement and enhanced antithrombotic therapy) plus standard PTS care or to the control group that received standard PTS care alone.

SIR reported that the study showed patients in the active arm had significantly greater improvement in their PTS severity than the patients in the control arm. This resulted in major improvement in self-reported quality of life through 6 months.

At baseline, 93% of patients presented with “severe” PTS, as classified by the Venous Clinical Severity Score. At 6 months, only 40% of patients in the stent treatment arm had severe disease. Given that severe PTS has been considered exceedingly difficult to treat, this shift is remarkable, noted the SIR press release.

Dr. Vedantham, who is an interventional radiologist and professor of radiology at WashU Medicine Mallinckrodt Institute of Radiology as well as a professor of surgery at WashU Medicine, discussed the C-TRACT study in the SIR press release.

“Many patients with PTS suffer in silence because few physicians are aware of this complication or know how to effectively treat it,” commented Dr. Vedantham. “This study suggests that even severe PTS is, in fact, a treatable condition in many patients.”

Dr. Vedantham continued, “Standard treatments such as anticoagulation and compression are important but for many patients, such treatments are not enough to improve leg symptoms and enable patients to function normally in their daily lives. C-TRACT shows that patients with moderate-to-severe PTS and large vein blockage could benefit greatly from endovascular stent treatment, so patients should consult with an interventional radiologist for proper evaluation and management.”