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Limited clinical data speak to the potential of bioresorbable scaffolds as a new therapy, and future studies will prove critical to inspiring a fourth revolution in PCI.

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In this study, we evaluate coaxial electrospun nanofibers with gelatin in the shell and polyvinyl (PVA) in the core as a potential vascular material by determining fiber surface roughness, as well as human platelet deposition and activation under varying conditions. PVA scaffolds had the highest surface roughness (Ra = 65.5 ± 6.8 nm) but the lowest platelet deposition (34.2 ± 5.8 platelets) in comparison to gelatin nanofibers (Ra = 36.8 ± 3.0 nm & 168.9 ± 29.8 platelets) and coaxial nanofibers (1 Gel: 1 PVA coaxial – Ra = 24.0 ± 1.5 nm & 150.2 ± 17.4 platelets; 3 Gel: 1 PVA coaxial – Ra = 37.1 ± 2.8 nm & 167.8 ± 15.4 platelets). Therefore, the chemical structure of the gelatin nanofibers dominated surface roughness in platelet deposition. Due to their increased stiffness, the coaxial nanofibers had the highest platelet activation rate – rate of thrombin formation, in comparison to gelatin and PVA fibers. Our studies indicate that mechanical stiffness is a dominating factor for platelet deposition and activation, followed by biochemical moieties, and lastly surface roughness. Overall, these coaxial nanofibers are an appealing material for vascular applications by supporting cellular growth while minimizing platelet deposition and activation.

Biodegradable polymeric coatings on cardiovascular stents can be used for local delivery of therapeutic agents to diseased coronary arteries after stenting procedures. This can minimize the occurrence of clinically adverse events such as restenosis after stent implantation. A validated mathematical model can be a very important tool in the design and development of such coatings for drug delivery. The model should incorporate the important physicochemical processes responsible for the polymer degradation and drug release. Such a model can be used to study the effect of different coating parameters and configurations on the degradation and the release of the drug from the coating. In this paper, a simultaneous transport-reaction model predicting the degradation and release of the drug Everolimus from a polylactic acid (PLA) based stent coating is presented. The model has been validated using in vitro testing data and was further used to evaluate the influence of various parameters such as partitioning coefficient of water, autocatalytic effect of the lactic acid and structural change of the matrix, on the PLA degradation and drug release. The model can be used as a tool for predicting drug delivery from other coating configurations designed using the same polymer-drug combination. In addition, this modeling methodology has broader applications and can be used to develop mathematical models for predicting the degradation and drug release kinetics for other polymeric drug delivery systems.