QRS width and QT time alteration due to geometry change in modelled human cardiac magnetograms

The influence of changing mesh geometries due to muscle contraction on computated biomagnetic fields of the human heart is investigated. To generate a detailed computer model of the ventricle and compare it to magnetocardiographic data, MCG and MRI were taken consecutively from the same proband. Two computer models were built from the MRI data at diastole and systole in order to assess the maximum deviation induced by geometry on the MCG. We could reproduce the structure of the measured MCG. The mesh geometry had a significant effect on the simulated magnetogram. QRS width differed by 15 ms and QT _max times differed by 20 ms between the two computer-generated MCG. Consequently, models for biomagnetic heart activity should take detailed geometry change during the heart cycle into account