Patient-Specific Study of Post-Ischemic Cardiac Ventricular Remodeling: A Passive Simulation of Structural Changes in Myofiber Orientation and Stiffness

Despite recent advances in the computational modeling of cardiovascular diseases and therapies, the effect of post-ischemic remodeling has not been thoroughly studied while considering the unloaded ventricles. Further evaluation is, therefore, needed in order to better understand the effect of alterations in myocardial structure. Herein, we have developed a patient-specific computational model of ischemic cardiomyopathy to assess the influence of microstructure and material change on passive ventricular mechanics. The biventricular geometry has been built and unloaded based on cardiac magnetic resonance (CMR) images of a 64-year-old male patient at end-diastole (ED). Different fiber orientations and material scales were assumed for the model. Results indicated that although some fiber structures produce similar end-diastolic pressure-volume relationships (EDPVRs), differences in initial stress-free shapes and strain patterns determine the subsequent damage to the myocardium. Moreover, stiffening the healthy region means lower myofiber strain. However, material change in the ischemic areas of the ventricles does not alter the passive fiber strain considerably. Such evaluations are required when choosing optimal therapies to alleviate the adverse effects of ischemic cardiomyopathy.