The post-morphological analysis of electrospun vascular grafts following mechanical testing

Vascular grafts provide promising scaffolds for patients recuperating from cardiovascular diseases. Since it is necessary to mimic the native vessel in order to overcome the limitations of currently employed synthetic prostheses, researchers are tending to focus on the design of electrospun biodegradable multi-layer scaffolds which involves varying either the polymer type or constructional properties in each layer which, in turn, reveals the importance of layer interactions and their composite effect on the final multi-layer graft. This study describes the fabrication of biodegradable single-layer tubular scaffolds from polycaprolactone and poly(L-lactide)caprolactone polymers composed of either randomly distributed or, preferably, radially oriented fibers. Subsequently, bi-layer scaffolds were fabricated with a randomly distributed inner layer and a radially oriented outer layer from various polymer couple variations. The study focuses on vascular graft production technology including its morphology and mechanical properties. The post-morphologies of single-layer and bi-layer tubular scaffolds designed for vascular grafts were investigated as a continuation of a previously performed analysis of their mechanical properties. The results indicate that the mechanical properties of the final bi-layer grafts were principally influenced by the radially oriented outer layers acting as the tunica media of the native vessels when the appropriate polymer couples were chosen for the sub-layers.