Current density estimation within a human heart including a boundary-element-torso model

A simulation study on pseudo current density estimation of the minimum-norm type with a computer model of the entire human heart (cellular automaton) is presented. The heart model is embedded in a homogeneous boundary element (BE) torso model. The torso surface consists of 154 isoparametric 9 node boundary elements. The electrocardiogram (ECG) and the magnetocardiogram (MCG) are computed following the bidomain theory. Reconstructions were performed from the simulated MCG on 37 frontal and 37 left lateral observation points by use of Tikhonov´s method or singular value decomposition. A surface in the middle of the atrial and ventricular myocardium and septum is assumed as reconstruction space. The regularization parameter λ is determined by the L-curve or the generalized-cross-validation method