Impedance incorporated implanted device provides a unique approach to monitor hemodynamics. The challenge of the use of this method is the optimization of electrode configurations. To alleviate this issue, a 3D thorax model is presented in this study. The model was developed from CT images of a patient, covering from the neck to the lower abdomen. A MATLAB-based program was developed and used to delineate different tissues/organs. The model contains 467 layers and 37 different types of tissues. Each layer had 262,144 pixels with a resolution of $1.0×1.0 mm2$, approximately $122×106 pixels$ (voxels) in total. This high-resolution model can be used as a virtual phantom to optimize electrode configuration for the monitoring of hemodynamics by an implanted device.