Sensitivity of the Magnetocardiogram to Surface Versus Internal Currents
David H. Cohen, A. Jost · Advances in cardiology · 2015
The MCG has been computed from the surface potential maps of a normal subject, using only currents confined to a surface layer two cm thick. The computed MCG was then compared with the measured MCG of that subject. This was the purpose of the computation: if the computed MCG agrees with the measured MCG, then the MCG is largely produced by 'surface-connected' currents; if there is poor agreement, then the MCG is largely produced by currents unavailable to the BCG and may be, therefore, unique. The results strongly favor the second conclusion; the computed MCG is much weaker than the measured MCG, and has the wrong polarity. The MCG is therefore mostly due to deep currents, and has the possibility of revealing cardiac information not available to the ECG.