Safety and Effectiveness of the Wrapsody Cell-Impermeable Endoprosthesis to Treat Dysfunctional Arteriovenous Grafts: Results from the Nonrandomized Arm of the WAVE Trial

PURPOSE: To describe the safety and effectiveness of the Wrapsody Cell-Impermeable Endoprosthesis (CIE) for restoring functionality of the arteriovenous graft (AVG) in hemodialysis patients who experienced venous outflow stenosis. MATERIALS AND METHODS: The nonrandomized arm of the Wrapsody Arteriovenous Access Efficacy (WAVE) trial comprised a single cohort of 112 patients with stenosis in the AVG of their venous outflow circuit who were treated with the CIE. The primary effectiveness endpoint was the 6-month target lesion primary patency (TLPP). The primary safety endpoint was the proportion of patients without any localized or systemic safety events through 30 days, affecting the access of the venous outflow circuit and resulting in a reintervention, hospitalization, or death. Six-month safety and effectiveness outcomes were compared with performance goals (PGs) based on historical data on stent grafts (TLPP PG, 60%; safety PG, 89%). Key secondary measures were the 12-month TLPP and the 6- and 12-month access circuit primary patency (ACPP). RESULTS: A significantly higher proportion of patients treated with the CIE were free from a localized or systemic safety event through 30 days than the safety PG (95.4% vs 89%; P = .016). The observed 6-month TLPP was significantly higher than the PG (81.4% vs 60%; P < .0001). At 12 months, the Kaplan-Meier estimate of TLPP was 60.3%; the ACPP at 6 and 12 months was 69.2% and 36.3%, respectively. CONCLUSIONS: The superior patency and confirmed safety profile of the CIE suggest that it is a safe and effective treatment for AVG outflow stenosis, offering a significant patency improvement relative to historical stent graft performance.