Background. Patient-specific active Fluid-Structure Interactions (FSI) model is a useful approach to non-invasively investigate the hemodynamics in the heart. However, it takes a lot of effort to obtain the proper external force boundary conditions for active models, which heavily restrained the time-sensitive clinical applications of active computational models.
Methods. The simulation results of 12 passive FSI models based on 6 patients’ pre-operative and post-operative CT images were compared with corresponding active models to investigate the differences in hemodynamics and cardiac mechanics between these models.
Results. It was found that there was no significant difference in shear stress and pressure difference on mitral valve leaflet (MVL) between passive and active models, but a significant difference was found in wall stress on the inner boundary of left ventricle (Endocardium). It was also found that flow shear stress and pressure difference on the MVL were significantly decreased after successful surgery in both active and passive models.
Conclusion. Our results suggested that the passive models may provide good approximated hemodynamic results at 5% RR interval, which is crucial for analyzing the initiation of systolic anterior motion (SAM). Comparing to active models, the passive models decrease the complexity of the modeling construction and the difficulty of convergence significantly. Therefore, with proper boundary conditions and sufficient clinical data, the passive computational model may be a good substitution model for the active model to perform hemodynamic analysis for left ventricle to investigate the mechanisms of the initiation of SAM.