A novel translational model of atherosclerosis, the ex vivo pump-perfused amputated human limb model

Sci Rep. 2024 Jul 27;14(1):17244. doi: 10.1038/s41598-024-67635-0.

Abstract

The preclinical study of atherosclerosis has traditionally centred around the use of small animal models, translating to large animal models, prior to first-in-man studies. We propose to disrupt this paradigm by designing an ex vivo pump perfused human limb model. The novel model consists of taking a freshly amputated limb and incorporating it into an ex situ pump-perfused bypass system (akin to extracorporeal membrane oxygenation), circulating warmed, oxygenated blood. The circuit incorporates an introducer sheath and guiding catheter for intravascular imaging and X-ray angiography. Regular monitoring is performed using blood gas analysis, aiming for physiological parameters. The model maintains oxygen saturations > 99% for the length of perfusion (up to 6-h). Clinical grade X-ray angiography, intravascular ultrasound and optical coherence tomography have been successfully performed. Indocyanine green, a near-infrared fluorescent dye that localises to atherosclerotic plaque, has been injected into the system and left to circulate for 90-min. Fluorescence reflectance imaging of the dissected arterial bed confirmed uptake in areas of calcific atherosclerotic plaque on intravascular imaging. This is the first demonstration of an ex vivo pump-perfused "living" limb experimental model of atherosclerosis, which shows promise for future studies in translational interventional imaging and molecular targeting.

Keywords: Atherosclerosis; Molecular targeting; Translational research.

MeSH terms

  • Amputation, Surgical
  • Angiography
  • Atherosclerosis* / diagnostic imaging
  • Extremities / blood supply
  • Humans
  • Perfusion
  • Plaque, Atherosclerotic / diagnostic imaging
  • Tomography, Optical Coherence
  • Translational Research, Biomedical