Abstract:
:We have developed an impedance magnetocardiogram (IMCG) system to detect the change of magnetic field corresponding to changes in blood volume in the heart. A low magnetic field from the electrical activity of the human heart--the so-called magnetocardiogram (MCG)--can be simultaneously detected by using this system. Because the mechanical and electrical functions in the heart can be monitored by non-invasive and non-contact measurements, it is easy to observe the cardiovascular functions from an accurate sensor position. This system uses a technique to demodulate induced current in a subject. A flux-locked circuit of a superconducting quantum interference device has a wide frequency range (above 1 MHz) because a constant current (40 kHz) is fed through the subject. It is shown for the first time that the system could measure IMCG signals at the same time as MCG signals.
journal_name
Phys Med Bioljournal_title
Physics in medicine and biologyauthors
Kandori A,Miyashita T,Suzuki D,Yokosawa K,Tsukada Kdoi
10.1088/0031-9155/46/2/403subject
Has Abstractpub_date
2001-02-01 00:00:00pages
N45-8issue
2eissn
0031-9155issn
1361-6560journal_volume
46pub_type
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