Determination of cardiac geometry from impedance measurements

The basic formulation and some preliminary results of the utilization of impedance based measurements for obtaining cardiac geometry information are presented. This geometrical information is required for forward and inverse bioelectric calculations and could be utilized to enhance the display of epicardial surface recordings. The measured potentials are affected by the strength of the source, the distances to the source and the sink electrodes, the conductivity of the volume and the shape of the epicardial surface. The formulation and preliminary results emphasize the estimation of epicardial recording Electrode coordinates from the impedance measurements. It is shown that the measurements can also yield information about the geometry of the boundary of the heart