Effect of a novel cannulation device for vascular access on AVF maturation in a goat carotid-jugular fistula model

Objective: The Ark is a 3-D printed titanium device designed to be implanted around the draining vein of an arteriovenous fistula (AVF) to facilitate vascular access. The purpose of this study was to assess AVF maturation after Ark implantation in a large animal model. Methodology: End-to-side AVFs were created between the carotid artery and jugular vein in nine pygmy goats that included three control (AVF only) and six experimental (AVF and Ark device) animals. For experimental animals, an Ark device was implanted approximately 10 cm downstream of the anastomosis at the time of AVF creation. Postoperative ultrasounds and cannulations of the jugular vein fistula were performed over 12 months. At the conclusion of the study, the AVF was ligated and Ark devices along with a segment of the arterialized vein and surrounding tissues were explanted for gross and histological assessment. Results: The control and experimental Ark groups exhibited increased dilation and flow as well as diminished depth underscoring the parallel developments in vascular attributes and AVF maturation between the two groups. Gross pathology, histology, and micro-CT imaging revealed intact endothelium, mature tissue integration throughout the porous Ark device, and no underlying stenosis. No adverse events such as foreign body reaction, skin or vessel erosion were identified. Conclusion: The study showed maturation without stenosis of the fistula in all animals. This study confirmed that the Ark device functions as a scaffold around the access vein, allows fistula maturation, and can be consistently cannulated without infiltrations over a 12-month period in a large animal model.