Pivotal Study of Endovenous Stent Placement for Symptomatic Iliofemoral Venous Obstruction

Background: Chronic venous insufficiency is characterized by inadequate venous return from the lower extremities, which may arise from intravenous obstruction after deep vein thrombosis or from extrinsic venous compression. The purpose of this study was to determine the safety and effectiveness of a dedicated endovenous stent for symptomatic iliofemoral venous obstruction. Methods: The VIRTUS trial (VIRTUS Safety and Efficacy of the Veniti Vici Venous Stent System [Veniti, Inc] When Used to Treat Clinically Significant Chronic Non-Malignant Obstruction of the Iliofemoral Venous Segment) was a prospective, international, single-arm, pivotal study of endovenous stent placement in patients with symptomatic iliofemoral venous obstruction. Patients included those with ≥50% obstruction on venography and Clinical, Etiology, Anatomic, Pathophysiology clinical classification ≥3, or at least moderate leg pain with a Venous Clinical Severity Score of 2 or greater. All patients were treated with a self-expanding nitinol stent developed for dedicated use in the venous system (Vici Venous Stent System, Veniti, Inc/Boston Scientific, Marlborough, MA). Patients returned for clinical and imaging follow-up visits at 1 month, 6 months, and 1 year. The primary safety outcome was freedom from major adverse events at 30 days. The primary effectiveness outcome was venographic primary patency at 1-year. Adverse events were adjudicated by a Clinical Events Committee, and all imaging including venograms, intravascular ultrasound, and Doppler examinations were assessed by respective core laboratories. Results: Between March 2015 and November 2016, 170 patients (127 chronic post-thrombotic, mean age 54 years, 56.4% female) at 22 sites underwent endovenous stent placement. Mean diameter stenosis was 78%, with 31.2% total occlusions. Mean lesion length was 111.3 mm, range 10 to 260 mm (mean 125.3 mm for post-thrombotic patients and 70.2 mm for nonthrombotic patients). Freedom from a major adverse event through 30 days was 98.8%. The 1-year primary patency rate for the entire group was 84.0%. Venographic patency rates for the nonthrombotic and chronic post-thrombotic groups were 96.2% and 79.8%, respectively. At 12 months, 64% (85/132) of patients demonstrated at least a 3-point reduction in Venous Clinical Severity Score. Conclusions: Twelve-month safety and effectiveness were demonstrated with the use of a dedicated venous stent to treat symptomatic iliofemoral venous obstructions, with reductions in clinical symptoms and improvements in quality of life, through 1-year follow-up. Clinical Trial Registration: URL: https://www.clinicaltrials.gov . Unique identifier: NCT02112877.