353 In Vivo Like Coronary Phantoms With Disease and Anisotropic Behaviour

Abstract

The main disadvantage of bench-top phantoms is their lack in disease and uniform tissue properties, causing inaccurate representation when testing stent implant for example. Here we replicate realistic arterial properties with lesions using 3D heterogenic multi-material soft-printing with fibre like microstructures. This “meta-material” concept to replicate anisotropic properties of coronary wall and soft plaque was established through computational modelling and 1kN load cell tensile testing to matched in vivo properties from literature. Size of fibre radii, number of fibres, their sinodal curve and material were all varied to replicate in vivo tissue properties. Without the fibre like micro-structures, the polymer base material exhibits a notably different stress-strain behaviour and values. Circumferential and longitudinal coronary artery properties were matched well (<0.01 MPA difference for 0.06 axial and 0.1 circumferential strain). Soft plaque was also replicated well for strains of up to 0.15 with less than 0.05 MPA difference. Hard calcified plaque can be printed. We were able to print the first patient-specific left main bifurcation with realistic wall properties and arterial soft and calcified plaque. In future, this will allow more accurate functional bench testing including flow and mechanical studies, such as stent implants, and allow better training opportunities.