Abstract Body: Introduction: Vascular trauma necessitates immediate surgical intervention to avoid limb loss or death. Autologous grafts, the current standard of care for small diameter (<6 mm) vessel replacement, are limited by vessel harvesting delays and size mismatches. Rapid fabrication of small diameter vessels with customizable size and shape could enable intraoperative manufacturing of regenerative vascular grafts.
Hypothesis: We hypothesized that Focused Rotary Jet Spinning (FRJS) can produce size and geometry customizable vascular grafts within minutes, which can provide immediate mechanical support for vascular function while potentiating cellular infiltration and neotissue formation.
Methods: Vascular grafts, fabricated using FRJS, were produced using poly(L-lactide-co-ε-caprolactone) with inner diameters ranging from 0.5-10 mm. Fabrication speeds and graft mechanical properties were assessed. Acellular vascular grafts were implanted as interposition grafts in the femoral artery and vein in rats and evaluated at one and four week endpoints. Functional assessments included blood flow, oxygen saturation, and relative hemoglobin. Histological stains were performed to evaluate cellular infiltration, extracellular matrix (ECM) deposition, and endothelial formation along the lumen surface.
Results: Produced in minutes, vascular grafts were fabricated with controllable fiber alignment, wall thickness, inner diameter, and graft geometry, including bifurcated and curved configurations. The grafts demonstrated adequate mechanical properties to withstand physiological pressures and retain sutures. Grafts implanted in femoral artery and vein positions maintained perfusion across a four week duration (n = 6 artery and vein implants per time point). The artery implants facilitated faster cellular infiltration at one week (73% ± 3.8% for artery, n = 5, and 17% ± 1.9% for vein implants, n = 6, avg. ± SEM), however, both artery and vein implants permitted cellular infiltration and ECM deposition throughout the full wall thickness at four weeks.
Conclusion: Vascular grafts fabricated with FRJS simultaneously achieve production speeds and graft customizability necessary to enable intraoperative manufacturing of structural implants for vascular trauma.