Imaging of bioelectric sources in the heart using a cellular automaton model.

The approach to solve the inverse problem of electrocardiography presented here is using a computer model of the individual heart of a patient. It is based on a 3D-MRI dataset. Electrophysiologically important tissue classes are incorporated using rules.

Imaging characteristics of different multichannel magnetocardiographic systems.

In this study a comparison of multichannel magnetocardiographic systems is performed with respect to the "detectable" information content. We investigate the lead-field matrices, the slope of the singular values and the source spaces of three different devices: the VectorView (Neuromag: magnetometer-gradiometer mixed device) of the BioMag Laboratory, Helsinki University Central Hospital (HUCH), the arrangement of electronically coupled magnetometers of the Physikalisch-Technische Bundesanstalt Berlin (PTB) and a virtual sensor geometry which was optimized for an improved slope of the singular values at the Institute of Biomedical Engineering, Karlsruhe.

Comparison of regularization techniques for the reconstruction of transmembrane potentials in the heart.

Computer simulations to reconstruct the transmembrane potential distribution were performed for an anisotropic finite element model of the heart. Transmembrane potential was reconstructed in the form of 3D patches. Test patterns generated with a cellular automaton were used.

Comparison of macroscopic models of excitation and force propagation in the heart.

Computer aided simulations of the heart provide knowledge of phenomena, which are commonly neither visible nor measurable with current techniques. This knowledge can be applied e.g.