Modeling current pathways for therapeutic electrical applications

In determining how various devices will provide therapeutic currents it is necessary to know the current pathways along with the current densities and voltage gradients in the tissues of interest and in other tissues that may be influenced. In order to obtain this information a high resolution, computer based model (3.8 million elements) was created using gated ECG MRI images from an adult male. The model used the finite difference approach to obtain the needed data. A user friendly, graphical interface was developed for a PC program. The features of the program along with examples from studying the electrical therapies of pacing and defibrillation will be given. It will be show that the conductivity of the entire thorax is important in determining the current pathways within the heart.