The porcine hemodialysis access model

Area of Science:

• Vascular Surgery
• Nephrology
• Biomedical Engineering

Background:

• End-stage renal disease (ESRD) necessitates hemodialysis, often requiring vascular access.
• Intimal hyperplasia (IH) is a primary cause of hemodialysis access failure.
• Existing animal models have limitations in replicating human IH.

Purpose of the Study:

• To establish a reliable porcine model of hemodialysis access that mimics human intimal hyperplasia (IH).
• To create a preclinical platform for evaluating interventions aimed at reducing IH-related access failure.

Main Methods:

• Optimized surgical techniques for creating porcine iliac artery-to-vein (IAV) fistulas and polytetrafluoroethylene (PTFE) IAV conduits.
• Assessed patency and venous outflow using venography and intravascular ultrasound (IVUS) over 64 days.
• Conducted histological analysis of vascular tissues at various time points.

Main Results:

• Porcine IAV fistulas and conduits demonstrated persistent patency with significant stenosis developing in outflow veins.
• Venography and IVUS revealed substantial diameter and area stenoses, indicative of IH, in both fistula and conduit outflow veins.
• Histological examination confirmed IH formation predominantly at venous anastomoses and central to these sites.

Conclusions:

• The developed porcine model effectively reproduces hemodialysis access-related intimal hyperplasia (IH) with measurable stenosis.
• This model provides a valuable tool for preclinical assessment of devices and techniques to mitigate IH in hemodialysis patients.