Invasive Evaluation of MCG-Localization Results Importance of Measured Electrophysiological Time Intervals

Magnetocardiography (MCG) is used as a clinical diagnostic tool for noninvasive 3-dimensional localization of cardiac sources. For evaluation of the localization results, different approaches are published by using various topographic reference methods. In the majority of cases, surface ECG was used as a time reference and the calculation of the equivalent current dipole was based on the presence of stable dipole patterns of the magnetic field. For example, the choice of the time points for localization of the site of an accessory pathway ranged from 10 up to 50 ms afiter onset of the delta-wave in patients with WPW-syndrome in the studies. Usually the accuracy of biomagnetic localization results, obtained by the described “conventional mode”, is approximately 1–3 cm.