Endovascular therapy added to standard care for post-thrombotic syndrome was associated with improved syndrome severity and quality of life (QOL) at six months compared with standard care alone in patients with moderate or severe post-thrombotic syndrome and iliac vein-obstruction, and was also associated with a higher risk of bleeding, according to results of the C-TRACT trial published April 13 in NEJM.

At 29 clinical centers across the U.S., the open-label, assessor-blinded trial randomized 225 patients with moderate or severe post-thrombotic syndrome (mean age, 55 years; 47% women; 67% White, 24% Black, 12% Hispanic or Latino) to either endovascular therapy (iliac-vein stent placement and enhanced antithrombotic therapy) plus standard care (n=113) or standard care alone (n=112), including compression therapy, anticoagulants, patient education, and wound and ulcer care.

At baseline, patients' average Venous Clinical Severity Score (VCSS) was 12.4/30 and Venous Insufficiency Epidemiological and Economic Study Quality of Life Questionnaire (VEINES-QOL) score was 39.3/100.

Due to crossover and additional withdrawals, only 102 patients received endovascular therapy, and stent deployment was successful in 98 cases. During follow-up, antithrombotic medication use was more common in the endovascular-therapy group, especially antiplatelet agents (71.3% vs. 21.0%).

At six months, results showed that the severity of post-thrombotic syndrome, the primary endpoint, was lower in the endovascular-therapy arm (mean VCCS, 8.1 vs. 10.0 in the nonendovascular group; adjusted difference, –2.0; p=0.001). Patients in the endovascular therapy group also had greater improvements in quality of life, as measured by both the VEINES-QOL score (62.8 vs. 48.6; adjusted difference, 14.5 points; p<0.001) and Medical Outcomes Study 36-Item Short-Form Health Status Survey score (56.0 vs. 49.9/100; adjusted difference, 6.1 points; p<0.001).

Of note, regarding safety endpoints, bleeding was more common in the endovascular-therapy group (11.6% vs. 3.6% of the nonendovascular group; p=0.03), driven mostly by nonmajor bleeding (9.8% vs. 2.7%, respectively). Both groups had similar rates of symptomatic recurrent venous thromboembolism and death.

"Relatively few affected patients receive focused treatment for post-thrombotic syndrome owing to a lack of awareness among the medical community with regard to available therapies and a lack of evidence of clinical benefit for such therapies," write study investigators Suresh Vedantham, MD, et al. "Although the observed difference between the groups in the mean VCSS is of modest size, many of the patients' scores shifted to lower severity categories on the post-thrombotic syndrome scales over a [six]-month period, a finding that was indicative of reduced life interference from venous disease."

In an accompanying editorial comment, Ronald Luiz Gomes Flumignan, MD, PhD, and Luis Carlos Uta Nakano, MD, PhD, note that the study's "most consequential unanswered question is durability. Metallic venous stents are permanent implants, yet the C-TRACT trial captures outcomes for only the first [six] months."

"Data at 12 to 24 months that would link patency trajectories to symptom outcomes are needed before stenting can be incorporated into routine guideline recommendations," they write. "The path forward is clear: follow these patients, characterize durability, and determine whether today's stent earns its place as tomorrow's standard of care."