FE models of the LV that incorporate myocardial contractility have been described and used to determine the effect of myocardial infarction on structure and function. We believe that large deformation finite element models of the LV are extremely powerful because of their ability to accurately calculate stress in the myofiber direction [Zhang et al, Ann Thorac Surg, In Press].

More important finite element models of this sort can simulate the effect of 'virtual' surgical procedures. For instance, we recently determined the effect of adjustable passive ventricular constraint on wall stress and pump function [Jhun et al, Ann Thorac Surg, 89:132, 2010].

Also, we have recently described a method for determining myocardial material properties non-invasively using FE modeling and optimization [Sun et al, J Biomech Eng, 131: 111001, 2009]. That method was subsequently used to determine the effect of the Dor Procedure (above) on the contractility of infarct borderzone [Sun et al, J Thorac and Cardiovasc Surg, 140: 233, 2010].

There have been numerous FE modeling studies of the aortic valve, either as a bioprosthesis or as native tissue. In contrast, the mitral valve is structurally more complex and includes the contracting left ventricular (LV) wall as a structural element. As a consequence, most FE models of the mitral valve assume that the papillary muscles are fixed in space. Examples include the work of Kunzelman et al, who generated the first FE model of an isolated mitral valve. Finite element models of the isolated mitral valve have now been used to determine the effect of artificial chordae on valve deformation, the effects of leaflet and annular curvature on leaflet stress, and the effects of innovative annuloplasty ring shape. More recently, modeling of the mitral leaflets has become more realistic and fluid structure interaction (FSI) has been added.

Recently we described the first model of the LV with mitral valve. The model was based on a sheep with a posterolateral MI that had developed 2+ ischemic MR [Wenk et al, Ann Thorac Surg, 89: 1546, 2010]. That model is currently being used to model the effects of undersized annuloplasty ring.

First Realistic Finite Element Model of Regional Biventricular Mechanics in a Patient with Tetrology of Fallot