Mass-Spring Model for Simulation of Heart Valve Tissue Mechanical Behavior

• DOI: 10.1007/s10439-011-0278-5
• Publication Date: 2011-02-24T15:32:49Z
• Authors: Peter E. Hammer; Michael S. Sacks; Pedro J. del Nido; Robert D. Howe
• Keywords: Aortic Valve; 0206 medical engineering; Models, Cardiovascular; 610; Animals; Humans; Computer Simulation; 02 engineering and technology; Shear Strength; 620

Heart valves are functionally complex, making surgical repair difficult. Simulation-based surgical planning could facilitate repair, but current finite element (FE) studies are prohibitively slow for rapid, clinically oriented simulations. Mass-spring (M-S) models are fast but can be inaccurate. We quantify speed and accuracy differences between an anisotropic, nonlinear M-S and an efficient FE membrane model for simulating both biaxial and pressure loading of aortic valve (AV) leaflets. The FE model incurs approximately 10 times the computational cost of the M-S model. For simulated biaxial loading, mean error in normal strains is <1% for both FE and M-S models for equibiaxial loading but increases for non-equibiaxial states for the M-S model (7%). The M-S model was less able to simulate shear behavior, with mean strain error of approximately 80%. For pressurized AV leaflets, the M-S model predicts similar leaflet dimensions to the FE model (within 2.6%), and the coaptation zone is similar between models. The M-S model simulates in-plane behavior of AV leaflets considerably faster than the FE model and with only minor differences in the deformed mesh. While the M-S model does not allow explicit control of shear response, shear does not strongly influence shape of the simulated AV under pressure.