Thromboresistance and functional healing in the COBRA PzF stent versus competitor DES: Implications for dual antiplatelet therapy

Abstract

Aims: The aim of this study was to investigate the COBRA PzF stent (C-PzF) with respect to thrombogenicity and healing versus conventional drug-eluting stents (DES) in dedicated preclinical models to evaluate their suitability for short-term dual antiplatelet therapy (DAPT). Methods and results: To examine acute thrombogenicity, the C-PzF durable polymer drug-eluting stent (DP-DES), and a bioabsorable polymer DES (BP-DES) were compared in a porcine arteriovenous shunt model and in a rabbit model to evaluate endothelial coverage at 14 days. Barrier function at 28 days in the rabbit was assessed in the former stents as well as in a polymer-free DES (PF-BES). The number of clots by scanning electron microscopy (SEM) was significantly less in the C-PzF and DP-EES versus the BP-EES. Endothelial coverage at 14 days was significantly greater in the C-PzF versus the DP-EES and BP-EES by CD31/PECAM-1 positive area in confocal microscopy (CM) (24.7% vs 11.9% vs 3.7%, respectively) and SEM (99.0% vs 29.6% vs 17.7%, respectively). Barrier protein expression by CM for p120/vascularendothelial cadherin complex was significantly greater in the C-PzF versus the DP-EES, BP-EES, and PF-BES (82.6% vs 12.8% vs 14.4% vs 18.1%, respectively). The percentage of Evan's Blue positive area was least in the C-PzF versus all groups (22.0% vs 70.7% vs 66.4% vs 55.2%, respectively). Conclusions: The C-PzF demonstrated a unique combination of thrombogenicity and healing advantages compared to contemporary DES and may be uniquely suitable for very short-term DAPT.