Comparison of Endothelial Barrier Functional Recovery after Implantation of a Novel Biodegradable Polymer Sirolimus-Eluting Stent in Comparison to Durable and Biodegradable Polymer Everolimus-Eluting Stents

Abstract Aims The advantage of biodegradable-polymer drug-eluting stents (BP-DES) versus durable-polymer (DP) DES remains uncertain. We compared neointimal formation and endothelial barrier function of new BP sirolimus-eluting stents (BP-SES, BuMA Supreme®) to other contemporary BP-DES, DP-DES, and bare metal stents (BMS). Methods and results Light microscopic assessment in swine coronary arteries showed comparable neointimal formation between BP-SES and DP everolimus-eluting stent (DP-EES). The performance of BP-SES was compared with DP-EES (Xience Xpedition®), BP-EES (Synergy®), and BMS (Multi-Link Vision®) at 45- and 90-days in rabbit ilio-femoral arteries using Evans blue dye (EBD) followed by immunostaining for endothelial barrier proteins (p120/vascular endothelial-cadherin [VE-cad]) to evaluate endothelial barrier function and scanning electron microscopy (SEM) to determine strut tissue coverage. BMS followed by BP-SES and BP-EES exhibited smaller EBD positive areas versus that of DP-EES at 45- and 90-days. p120/VE-cad immunostaining and SEM-determined strut coverage was greater at 45- and 90-days for BMS followed by all DESs. Regardless of stent type, the lack of p120/VE-cad co-localization showed greater leukocyte and platelet aggregation. Conclusion Three types of DES showed different endothelial healing pattern regardless their equivalent suppression of neointimal formation.