Modeling of myocardial splitting due to deep penetration

• Published in: CONSTITUTIVE MODELS FOR RUBBER VI p. 449
• Main Authors: Forsell, Caroline, Gasser, T. Christian
• Format: Conference Proceeding
• Language: English
• Published: 2010
• ISBN: 9780415563277; 0415563275

The risk for pacemaker lead perforation, a rare but serious clinical complication, is thought to be minimized by perforation resistant device design. Fracture properties of ventricular tissue play a central role in such optimization studies, however, this information is currently not provided by the open literature; even failure models for soft biological tissue in general are rare. Incompressible finite deformations, material nonlinearity and time-dependent anisotropic properties require sophisticated approaches to identify and model failure of such a material. In this study we investigated myocardial failure due to deep penetration, where previously collected data from in-vitro experiments are integrated in a non-linear Finite Element model. In details, the proposed model describes tissue splitting by a cohesive process zone, and hence, tissue failure is modeled as a gradual process, where all inelastic phenomena are accumulated and mathematically captured by a traction separation law. The cohesive zone is embedded in a fibrous bulk material thought to capture the properties of passive myocardial tissue, where a transversely isotropic hyper-elastic constitutive description proposed in the literature was utilized. The developed numerical model integrates latest experimental data and is able to replicate quantitative and qualitative data from ventricular penetration experiments.