2002 Volume 26 Issue 4 Pages 625-628
We performed three-dimensional vector measurement of magnetocardiograms (MCGs) for normal subjects and subjects with Wolff-Parkinson-White (WPW) syndrome, using a three-dimensional second-order gradiometer connected to 39-channel SQUIDs, which can simultaneously detect magnetic field components perpendicular to the chest wall (Bz) and those tangential to the chest wall (Bx,By). In order to analyze the accessory pathway of WPW syndrome, source estimation to the delta wave was performed using the equivalent current dipole (ECD) method.
Magnetic field pattern Bz of the delta wave for WPW syndrome was not a dipole pattern, and it was difficult to estimate sources. Magnetic field patterns Bx and By, however can provide information on constraint conditions for estimation of multiple sources. It was found by three-dimensional measurement that the estimation of the accessory pathway received the effects of a repolarization process of the heart atrium when the accessory pathway was located far from a sinoatrial node. It was shown that three-dimensional MCG measurements are effective for detailed analysis of heart activity.
