Numerical simulation in electrical cardiometry

This study is concerned with the direct problem of Electro Cardiometry (ECM) technique, and the associated thoracic electrical bioimpedance (TEB). We present a mathematical model for the hemodynamic of the aorta, the change in the electrical conductivity of the blood, and the electrical field problem equivalent to the ECM procedure. Having in view that anatomy plays a key role in investigating the ECM-TEB problem we used a 3D computational domain produced by medical image based reconstruction techniques. The mathematical model is solved by numerical simulation in the finite element method (FEM) technique. Analytic formulae for the electrical conductivity of the blood are available, however, when investigating the hemodynamic of the aorta flow considering an anatomically realistic computational domain, these results are difficult (if possible) to use as such. To circumvent this difficulty we defined an equivalent conductivity based on analytic results, by averaging techniques that outline the sensitivity of TEB to the aorta blood flow dynamics. The work reported here addresses the direct problem of ECM-TEB, aiming at assessing the sensitivity of TEB to the flow parameters. Its solution opens the path to the inverse EMC-TEB problem, with the objective of deciphering the flow dynamics out of EMC-TEB experimental data.