The pCONUS HPC: 30-Day and 180-Day In Vivo Biocompatibility Results

BackgroundEndovascular stents are commonly used during neurointerventional procedures; however, the concomitant use of dual anti-platelet treatment (DAPT) can limit their use. There is a need to develop stent coatings that mitigate requirement for DAPT. MethodsThe hydrophilic polymer coating is a novel glycan-based multilayer polymer that inhibits platelet adhesion. After Institutional Animal Care and Use Committee approval, 18 New Zealand white rabbits (mean weight 4.020.51kg) were commenced on DAPT (ASA 10mg/kg/day and clopidogrel 10mg/kg/day). A bare nitinol pCONUS and coated pCONUS HPC were implanted into the common carotid arteries of each rabbit. Histological examinations were performed at 30days (n=9) and 180days (n=8) to assess the acute and chronic inflammatory reactions to the pCONUS HPC. Wilcoxon/Kruskal-Wallis and ANOVA were used with p value<0.05 considered as significant. ResultsThere is no statistically significant difference in inflammation within the intima/media or adventitia at 30days (p=0.3901 and p=1, respectively) or at 180days (p=0.144 and p=1, respectively) between pCONUS and pCONUS HPC cohorts. There is no significant difference in the presence of granulomas or giant cells between the cohorts at either 30days (p=1 and p=0.8363) or 180days (p=1.00 and p=0.149). At 30days and 180days, there was near-complete endothelialisation of the stent struts and no significant difference between the pCONUS or pCONUS HPC (p=0.7832 and p=0.334, respectively). Conclusion pCONUS HPC stents do not elicit an acute or chronic inflammatory response in vivo with no significant difference in the tissue response to bare nitinol pCONUS stents or pCONUS HPC stents.