Magnetocardiography (MCG) is a technique to measure the magnetic fields produced by electrical currents in the heart using extremely sensitive devices such as the superconducting quantum interference device (SQUID). If the magnetic field is measured using a multichannel device, a map of the magnetic field is obtained over the chest; from such a map, using mathematical algorithms that take into account the conductivity structure of the torso, it is possible to locate the source of the activity. For example, sources of abnormal rhythms or arrhythmia may be located using MCG.
| Magnetocardiography | |
|---|---|
 The heart's electromagnetic field | |
| Purpose | records the magnetic fields generated by the heart |
History
editThe first MCG measurements were made by Baule and McFee[1] using two large coils placed over the chest, connected in opposition to cancel out the relatively large magnetic background. Heart signals were indeed seen, but were very noisy. The next development was by David Cohen,[2] who used a magnetically shielded room to reduce the background, and a smaller coil with better electronics; the heart signals were now less noisy, allowing a magnetic map to be made, verifying the magnetic properties and source of the signal. However, the use of an inherently noisy coil detector discouraged widespread interest in the MCG. The turning point came with the development of the sensitive detector called the SQUID (superconducting quantum interference device) by James Zimmerman.[3] The combination of this detector and Cohen's new shielded room at MIT allowed the MCG signal to be seen as clearly as the conventional electrocardiogram, and the publication of this result by Cohen et al.[4] marked the real beginning of magnetocardiography (as well as biomagnetism generally).
Magnetocardiography is used in various laboratories and clinics around the world, both for research on the normal human heart, and for clinical diagnosis.[5]
Clinical implementation
editMCG technology has been implemented in hospitals in Germany. The MCG system, CS MAG II of Biomagnetik Park GmbH, was installed at Coburg Hospital in 2013. The CS-MAG III system was installed at the Dietrich Bonhoeffer Hospital, Neubrandenburg, and the Charité Hospital, Berlin, in 2017.[citation needed]
The first MCG centre in Asia is set up in Hong Kong, adapting the same technology as Hamburg, and set up by the same team.[citation needed]
Genetesis, a medical imaging company based in Mason, OH, is developing a device called the CardioFlux that leverages MCG technology to diagnose heart-related conditions.[6]
See also
editReferences
edit- ^ Baule, Gerhard; McFee, Richard (1963). "Detection of the magnetic field of the heart". American Heart Journal. 66 (1). Elsevier BV: 95–96. doi:10.1016/0002-8703(63)90075-9. ISSN 0002-8703. PMID 14045992.
- ^ Cohen, D. (1967-05-05). "Magnetic Fields around the Torso: Production by Electrical Activity of the Human Heart". Science. 156 (3775). American Association for the Advancement of Science (AAAS): 652–654. Bibcode:1967Sci...156..652C. doi:10.1126/science.156.3775.652. ISSN 0036-8075. PMID 6023659. S2CID 40061168.
- ^ Zimmerman, J. E.; Thiene, Paul; Harding, J. T. (1970-03-15). "Design and Operation of Stable rf-Biased Superconducting Point-Contact Quantum Devices, and a Note on the Properties of Perfectly Clean Metal Contacts". Journal of Applied Physics. 41 (4). AIP Publishing: 1572–1580. Bibcode:1970JAP....41.1572Z. doi:10.1063/1.1659074. ISSN 0021-8979.
- ^ Cohen, David; Edelsack, Edgar A.; Zimmerman, James E. (1970). "Magnetocardiograms taken inside a shielded room with a superconducting point-contact magnetometer". Applied Physics Letters. 16 (7). AIP Publishing: 278–280. Bibcode:1970ApPhL..16..278C. doi:10.1063/1.1653195. ISSN 0003-6951.
- ^ Koch, Hans (2004). "Recent advances in magnetocardiography". Journal of Electrocardiology. 37. Elsevier BV: 117–122. doi:10.1016/j.jelectrocard.2004.08.035. ISSN 0022-0736. PMID 15534820.
- ^ "CardioFlux". Retrieved August 17, 2022.