VESS18 - Comparison of 12-month reintervention and index of patency outcomes following treatment with a novel cell-impermeable endoprosthesis versus percutaneous transluminal angioplasty

Objectives: Perform a post-hoc analysis comparing reintervention rates and index of patency function through 12 months in hemodialysis patients with an arteriovenous fistula (AVF) receiving treatment with either a novel cell-impermeable endoprosthesis (CIE) or percutaneous transluminal angioplasty (PTA) for venous outflow stenosis.

Methods: A prospective, multicenter, international trial was conducted across 43 centers in the United States, South America, and the United Kingdom. The randomized arm of the trial included patients with venous outflow stenosis or occlusion in their AVF who were randomized 1:1 to treatment with the CIE or PTA. The safety profile of the CIE was determined based on the proportion of patients without any localized or systemic safety events. Sensitivity analyses were conducted on 12-month follow-up data to calculate the proportion of patients in the AVF cohort who required reintervention of the target lesion, any reintervention, and the index of patency function (IPF). IPF was defined as the time interval specified (or access abandonment) divided by the number of interventions, inclusive of the index procedure. Patients without reinterventions were included as total time in the study within the interval, provided the patient completed follow-up within at least the lower bound of each visit window. The log-rank test was used to determine statistical significance between cohorts (p-value threshold 0.05).

Results: A total of 245 were analyzed, 122 patients treated with the CIE, and 123 treated with PTA. A similar proportion of patients were free from safety events 30 days post procedure (CIE: 96.6%; PTA: 95.0%; p=0.53). The mean IPF over the 12-month follow-up period was significantly longer for patients treated with the CIE versus PTA (CIE: 247±124; PTA: 187.5±122.1; p=0.0008). The proportion of patients who required reintervention of the target lesion was significantly lower in the CIE cohort (30.6% vs. 60.1%, p< 0.0001, Figure 1). Similarly, the proportion of patients treated with the CIE who required any reintervention was significantly lower than the PTA cohort (44.5% vs. 65.0%, p=0.001, Figure 2).

Conclusions: The post-hoc analysis demonstrates a significant reduction in the target lesion and access circuit reintervention rates for the CIE as compared to PTA. Similarly, the CIE exhibited a significantly higher IPF through 12 months. These benefits may translate to better patient experience and potential long-term cost savings to the healthcare system.