Non-Newtonian pulsatile shear stress assessment: a method to differentiate bioresorbable scaffold platforms

In-vitro and in-silico studies have shown that the implantation of coronary stent or scaffold induces changes in local haemodynamic microenvironment.Coronary angiography and optical coherence tomography (OCT) data were used to perform three-dimensional reconstruction of the right coronary of two healthy mini pigs after implantation of a 3.0 Â 18 mm Absorb BVS with strut thickness of 157 mm (Abbott Vascular, USA) and 3.0 Â 14 mm ArterioSorb with strut thickness of 95 mm (Arterius, UK) (Figure).Computational fluid dynamic (CFD) techniques were implemented to simulate pulsatile coronary blood flow.Quemada equation was implemented for shear-thinning blood rheology which integrates haematocrit and shear rate.Endothelial shear stress (ESS) was calculated as the product of local blood viscosity and near-wall velocity gradient.Strut protrusion analysis by OCT was performed using a dedicated software (QCU-CMS v. 16.9, Medis, Leiden, Netherlands).