Incorporation of Perfusion Information Into a Finite Element Model of the Left Ventricle

The 4D NCAT and XCAT phantoms have been found useful in the simulation of medical image data especially SPECT, PET, CT and more recently MRI. The phantoms provide realistic models of the anatomical structures and respiratory and cardiac motions of humans. When combined with accurate models of the physics and instrumentation involved in the imaging process, accurate and realistic simulation data that closely mimic those acquired from patients can be obtained. However, a limitation to the 4D NCAT/XCAT series of phantoms is that the cardiac motion incorporated in the NCAT/XCAT was based on a single set of gated tagged MRI data of a particular normal male subject so that the definitions of pathologies such as ischemia and infarction in the phantoms had no physiological basis. Our previous work sought to overcome this limitation by incorporating into the phantoms, a physiologically based finite-element (FE) mechanical model for the left ventricle (LV). These model was found to accurately simulate both the normal motion of the LV as well as abnormal motions due to ischemia [1] and infarction [2]. One of the primary limitations of these models is that they have overly simplistic geometries (Figure 1) representing the ischemic or infarcted regions. In order to produce more realistic geometries of the ischemic/infarcted regions, the 4D Perfusion CArdiac-Torso (PCAT) phantom was utilized to define a low perfusion region in the LV [3]. The objective of this study was to demonstrate the ability to incorporate this perfusion information directly into an FE model of the left ventricle.