Vascular access animal models used in research

Abstract

Purpose: To provide a systematic literature review on effectiveness of arteriovenous fistula (AVF) and Shunt (AVS) research animal models.

Background: Due to advancing human population age, there is increased incidence of patients suffering from vascular and renal diseases leading to dialysis access using AVF and/or AVS. During those interventions native venous or synthetic grafts are arterialized. Despite temporary good patency, complications are a consequence of neointimal hyperplasia (NIH) development that contributes to patients' morbidity and mortality. Basic research attempts to elucidate the pathomechanisms, therefore the small and large animal models are becoming attractive.

Methods: Medline search (within 1966-2018) was performed on AVF/AVS animal models. Studies fulfilled following criteria: (1) reported complete material-methods-results section, (2) included statistically significant number of animals, (3) provided statistically significant results. 55 articles were identified encompassing six animal species used.

Results: Large animal models include creation of AVF and AVS in pig, sheep and dog. Porcine animal models use pelvic or femoral vessels, ovine use the common carotid artery (CCA) and jugular vein (JV). Canine animal models use the femoral vessels. Small animal models use rabbit (CCA/JV), rat (JV/CCA, abdominal aorta /Vena cava inferior and femoral artery/femoral vein) and mouse (aortocaval and supraortic AVF models).

Conclusions: Large animal models are best for haemodynamic shear stress studies and in vivo evaluation of new synthetic vascular grafts. Small animal models, especially the genetically manipulated ones, are ideal for analysis of molecular and cellular pathomechanisms. The selection of animal species to be used depends on the addressed research question.

Keywords: AVF; AVS; Animal models; Arterialised veins; ESRD; Neointimal hyperplasia.