Analytical and Numerical Studies of Volume Measurement using Conductance Catheter Techniques

Calculation of intra-ventricular blood volume using the impedance electrode technique suffers from inaccuracy arising from irregularity in ventricular geometry and non-uniformity in imposed electric fields. This is particularly evident in the right ventricle. To investigate this problem, we present analytical and numerical solutions for the electric field in a conductor with asymmetrical source electrodes. The results show the effects of field non-uniformity, and a potential improvement in using dual-excitation electrodes. We plan to extend these techniques to develop improved electrode configurations for use in blood volume measurements in the right ventricle