Magnetocardiogram
The magnetocardiogram (abbreviated MKG ) is the recording and representation of the magnetic field of the heart, which is created by the electrophysiological activity of the heart muscle cells. The recording is usually made with highly sensitive magnetic field sensors, so-called SQUIDs . The recording of the magnetocardiogram is contactless, non-invasive and purely passive. The body is not exposed to any energy or radiation during the measurement.
The heart's magnetic field corresponds exactly to its electrophysiological excitation. However, since the magnetic field lines, in contrast to the electrical signals, are only marginally influenced by the body tissue, a very precise conclusion about the electrophysiological function of the heart muscle is possible.
advantages
- By detecting the magnetic field, eddy currents can also be displayed within the heart muscle that can not be recorded with a surface EKG .
- Acquisition is very easy and convenient, since no electrodes have to be attached, no contrast media are necessary and the patient does not even have to undress.
disadvantage
The magnetic fields of the heart are very weak, they are in the range of about 20 to 80 picotesla . For comparison: The geomagnetic field in Central Europe is around 48 µT, around a million times stronger. Therefore, external interference must be carefully shielded and suppressed.
See also
literature
- Andrä, W., Nowak, H. (Ed.): Magnetism in Medicine: A Handbook , Wiley-VCH Weinheim, 2nd edition 2006 (English) ISBN 3-527405-58-5
Web links
- Biomagnetic center of the University of Jena with a short introduction to biomagnetism (English) and a picture gallery worth seeing, accessed on February 8, 2010
- Biomagnetic Diagnostic Systems Jena with description of the system for magnetic field imaging, accessed on February 8, 2010
