Interwoven nitinol stent-assisted arteriovenous fistula maturation: 2 year-outcomes of a single center experience.

Objectives: The aim of this study was to report 2-year outcomes of interwoven nitinol (Supera^TM) stent-assisted arteriovenous fistula (AVF) maturation in patients who presented with non-matured AVF.

Methods: We reviewed the clinical data of 20 patients who presented with non-matured AVF (19 patients with brachiocephalic AVF and 1 patient with radiocephalic AVF) and underwent balloon angioplasty followed by Supera^TM stenting in the cephalic vein for long-term hemodialysis between January 2017 and January 2022. The outcomes were evaluated in these patients in terms of technical success, post-intervention complications, reintervention, and cumulative patency (6 months, 1 year, and 2 years).

Results: The study included 20 patients who presented with non-matured AVF. The mean age of the patients was 65 years (range, 40-85). The Supera^TM stents of size 6.5 mm were used in 15 patients (75%), and those of 7.5 mm and 5.5 mm were used in 4 (20%) and 1 (5%) patient, respectively. The average stent length was 99.5 mm (range, 80-120). Technical success was achieved in all patients. Early use within 1 week by needling at the Supera^TM stent segment (cannulation zone) was successful in all patients without any complications. The mean follow-up time was 24.5 months. During the follow-up period, reinterventions to maintain the function of AVF were performed in 8 patients (40%) (7 patients with juxta-anastomotic stenosis, 1 patient with in-stent restenosis). The reintervention rate was 0.39 procedures per patient per year. The primary patency at 6 months, 1 year, and 2 years were 85.5%, 62.6%, and 54.2%, respectively. The assisted primary patency at 6 months, 1 year, and 2 years were 95%, 84.5%, and 78.8%, respectively.

Conclusions: The use of the Supera^TM stent to improve the AVF maturation rate was associated with acceptable outcomes at 2 years. Its benefit over other strategies was the early use of the access for hemodialysis.