3D-printed shape memory poly(alkylene terephthalate) scaffolds as cardiovascular stents revealing enhanced endothelialization.

Cardiovascular diseases are the leading cause of death and current treatments such as stents still suffer from disadvantages. Balloon expansion causes damage to the arterial wall and limited and delayed endothelialization gives rise to restenosis and thrombosis. New more performing materials that circumvent these disadvantages are required to improve the success rate of interventions. To this end, we investigated the use of a novel polymer, poly(hexamethylene terephthalate), for this application. We optimized the synthesis to obtain polymers with high molar masses up to 126.5 kg/mol and performed a thorough chemical and thermal analysis. We 3D-printed the polymers into personalized cardiovascular stents using the state-of-the-art solvent-cast direct-writing technique, established the potential of these stents to expand using their shape memory behavior and showed that the stents are more resistant to compression than the PLLA benchmark. Furthermore, we demonstrated the polymer's hydrolytic stability in an accelerated degradation study of six months. Finally, the stents were subjected to an in vitro biological evaluation, revealing that the polymer is non-hemolytic and supports significant endothelialization after only 7 days, demonstrating the enormous potential of these polymers to serve cardiovascular applications. This article is protected by copyright. All rights reserved.