3d Reconstruction and Nonlinear Finite Element Analysis of the Embryonic Left Ventricle

Changes in mechanical loading in the developing heart produce changes in morphology and mechanical material properties [1–3]. Understanding the relationship of these changes to mechanical stress and strain in the left ventricle requires a geometrically accurate model of the entire ventricle including the trabecular pattern and material property, boundary condition, and loading specification. A 3D reconstruction and finite element technique were developed to reconstruct the heart from serial confocal sections and calculate stress and strain distributions over the volume for the passive state. Control hearts and two treatments, pressure overload and pressure underload, were modeled. The results show that stresses in the trabeculae are much larger than those in the ventricular walls. Strains in the pressure-overloaded hearts were significantly smaller than in control or underloaded, indicating the stiffer material properties more than compensate for the increased internal pressure.