Abre 24-Month Study Outcomes and Subgroup Analyses

During a session on Monday, June 6, that focused on advances in endovascular therapy of deep venous obstructions, Erin Murphy, MD, from Sanger Heart & Vascular Institute in Charlotte, North Carolina, shared the results of a study to evaluate the safety and effectiveness of the Abre venous self-expanding stent system (Medtronic) for treatment of symptomatic iliofemoral venous outflow obstruction. The Abre stent is a nitinol stent that has an open cell design with 3 offset connection points. It comes in diameters up to 20 mm and lengths up to 150 mm. It has an over-the-wire delivery system; is 9 Fr 0.035" compatible; and has a triaxial catheter and thumbwheel activated deployment.

The prospective, nonrandomized, single-arm study included 200 subjects from 24 global sites (16 US, 8 EU) with post-thrombotic syndrome (PTS), nonthrombotic iliac vein lesion (NIVL), or acute deep vein thrombosis (aDVT). Follow-up was through 36 months. Primary endpoints included primary patency at 12 months meeting the following criteria: freedom from occlusion of the stented segment of the target lesion; freedom from restenosis 50% or more of the stented segment of the target lesion; freedom from clinically driven target lesion revascularization (CD-TLR); and major adverse events at 30 days post stenting.

The majority of patients were female (66.5%; 133/200), and 52% had a previous history of venous thromboembolism (VTE). Of those presenting with PTS, 35.8% (34.95) had a complete venous occlusion confirmed by the core lab. Primary endpoint outcomes included a rate of major adverse events within 30 days of 2%, and a primary patency at 12 months of 88%.

After 24 months, sustained effectiveness was seen through 720 days with a primary patency rate of 86.2% and a freedom from CD-TLR rate of 91.1%. Primary patency through 24 months was 76.8%, 83.3%, and 98.6% in PTS, aDVT, and NIVL groups, respectively. No stent fractures or delayed stent migrations were reported through 24 months. All patient groups demonstrated sustained and clinically meaningful improvements in quality-of-life measures and venous functional assessment scores at 24 months. “These data demonstrate that the Abre venous stent remains a safe and effective treatment for iliofemoral venous obstructive disease out to 24 months,” Dr. Murphy concluded.