Interwoven Nitinol Stents to Treat Radiocephalic Anastomotic Arteriovenous Fistula Stenosis

Abstract

Purpose: To determine the clinical outcomes in hemodialysis patients after implantation of a Supera stent to treat juxta-anastomotic stenosis in radiocephalic arteriovenous fistulas (AVF).

Materials and methods: A single-center retrospective study was conducted of 42 consecutive patients (mean age 66.7 years, range 40-84; 26 men) who had a failing AVF due to juxta-anastomotic stenosis treated with the interwoven Supera stent between February 2014 and February 2018. A third of the patients had previous juxta-anastomotic intervention (either balloon angioplasty or open surgical revision).

Results: The stent was inserted successfully in all patients. Overall mean follow-up was 12.2±8.2 months (range 3.8-38.3). Juxta-anastomotic segment primary patency estimates at 6 and 12 months were 92.5% and 59.8%, respectively, with assisted primary patency rates of 97.5% and 92.9%. Reintervention (elective drug-coated balloon angioplasty) occurred at a rate of 0.31 procedures/year. Two AVFs thrombosed during the 1-year follow-up and were revascularized using balloon angioplasty. Ultrasound measurements of brachial artery flow rates increased significantly from 543.5±96.72 mL/min (range 430-644) before intervention to 919.2±355.9 mL/min (range 200-1600) after intervention (p=0.047). Arterial pressures on hemodialysis improved from -142.3±24.9 mm Hg (range -100 to -180) to -123.4±21.9 mm Hg (range -100 to -184; p=0.051). No AVFs were lost or abandoned during the follow-up period.

Conclusion: The interwoven Supera stent is a promising treatment for failing AVFs with juxta-anastomotic stenosis. Encouraging 1-year primary and assisted primary patency was demonstrated, with a low reintervention rate. This treatment facilitates long-term maintenance of AVF vascular accesses.

Keywords: arteriovenous fistula; hemodialysis; interwoven stent; juxta-anastomotic stenosis; radiocephalic dialysis access; reintervention; restenosis; vascular access.