title: Numerical simulation of the failure of ventricular tissue due to deep penetration: the impact of constitutive properties.
abstract: Lead perforation is a rare but serious clinical complication of pacemaker implantation, and towards understanding this malfunction, the present study investigated myocardial failure due to deep penetration by an advancing rigid punch. To this end, a non-linear Finite Element model was developed that integrates constitutive data published in the literature with information from in vitro tensile testing in cross-fibre direction of porcine myocardial tissue. The Finite Element model considered non-linear, isotropic and visco-elastic properties of the myocardium, and tissue failure was phenomenologically described by a Traction Separation Law. In vitro penetration testing of porcine myocardium was used to validate the Finite Element model, and a particular objective of the study was to investigate the impact of different constitutive parameters on the simulated results. Specifically, results demonstrated that visco-elastic properties of the tissue strongly determine the failure process, whereas dissipative effects directly related to failure had a minor impact on the simulation results. In addition, non-linearity of the bulk material did not change the predicted peak penetration force and the simulations did not reveal elastic crack-tip blunting. The performed study provided novel insights into ventricular failure due to deep penetration, and provided useful information with which to develop numerical failure models.
authors.affiliation: Department of Solid Mechanics, School of Engineering Sciences, The Royal Institute of Technology (KTH), Osquars Backe 1, SE-100 44 Stockholm, Sweden. carfor@kth.se
authors.forename: Caroline
authors.initials: C
authors.lastname: Forsell
authors.forename: T Christian
authors.initials: TC
authors.lastname: Gasser
mesh_terms: D000818:Animals; D001696:Biomechanical Phenomena; D006348:Cardiac Surgical Procedures / Q000009:adverse effects*; D004548:Elasticity; D020342:Finite Element Analysis; D006352:Heart Ventricles / Q000293:injuries* / Q000503:physiopathology; D066298:In Vitro Techniques; D008955:Models, Cardiovascular; D017711:Nonlinear Dynamics; D010138:Pacemaker, Artificial / Q000009:adverse effects*; D013314:Stress, Mechanical; D034421:Sus scrofa; D013718:Tensile Strength; D014783:Viscosity