Fabricating synthetic, small-diameter vascular templates via touch-spinning

Abstract

Cardiovascular diseases remain the leading cause of death worldwide, highlighting the critical need for effective treatment options. Current commercially available grafts for coronary bypass procedures exhibit high failure rates due to mechanical mismatch with native blood vessels. This study investigated the use of touch-spinning to fabricate vascular templates that exhibit similar architecture and mechanical properties to native blood vessels. Polydioxanone (PDO) and PDO/collagen I templates were fabricated in a crosshatch pattern at 25° and 40° along the longitudinal axis. The templates were mechanically evaluated and compared to the internal mammary artery (IMA) and saphenous vein (SV) reference values. Fiber alignment analysis confirmed the intended crosshatch patterns were achieved. Mechanical testing revealed that PDO/collagen 40° templates exhibited the best overall performance. For the longitudinal uniaxial test, all templates exhibited similar mechanical properties to the native blood vessels. Circumferentially, all templates surpassed arterial and venous strength benchmarks, but displayed lower percent elongation values compared to the saphenous vein. Suture retention and burst pressure assessments revealed opportunities for further optimization. The results from this study demonstrate the potential for touch-spinning in manufacturing synthetic vascular grafts that can be used for bypass grafting surgeries.