Three-dimensional MCG Analysis with Independent Component Analysis

Abstract

We performed three-dimensional vector measurement of magnetocardiograms (MCGs) for normal subjects and for a patient 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 tangential to the chest wall (Bx, By). In order to discriminate the accessory pathway of WPW syndrome, Independent Component Analysis (ICA), having a time window (48 ms) for analysis, was applied to the MCG data of the WPW patient.
ICA is a useful method for separating independent signals from overlapping signals. We succeeded in carrying out dynamic ICA by changing the analytical interval timewise, and in separating the excitement due to the WPW syndrome patient's accessory pathway from the normal pathway.