A Versatile Engineering Platform for the Fabrication of Prosthetic Venous Valves Using Electrospinning.

Abstract

Chronic venous insufficiency caused by valvular incompetence affects millions. Yet, functional prosthetic venous valves (PVVs) remain elusive. Previous concepts failed due to thrombosis and leaflet thickening caused by vascular cell hyperplastic overgrowth. Here, we address these issues by developing a fabrication platform for percutaneous PVVs by fully embedding the stent struts in electrospun fibers that extend luminally to form thin leaflets. This approach offers unique advantages: the electrospun matrix, with spatially controlled porosity, separates the leaflets from hyperproliferating vascular cells and the stent struts from the blood. Its continuity with the leaflets eliminates the need for anchoring points on the stent and associated fixation methods. As a result, stents of any type, cell design or length can be employed, with valve placement possible at any position. We demonstrate these benefits by fabricating bicuspid valves using segments of commercial stents and either single or multiple materials via dual electrospinning, such as thermoplastic polyurethane (TPU) lined with elastin-like recombinamers (ELRs). The ELR/TPU constructs exhibit minimal platelet adhesion, no hemolysis, and support endothelialization in vitro. Functional evaluation confirms excellent hydrodynamic performance. Finally, the platform's potential for other applications is shown with tricuspid small diameter pediatric heart valves successfully tested according to ISO 8540.