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Chinese Science Bulletin

, Volume 47, Issue 22, pp 1861–1863 | Cite as

A high-Tc dc-SQUID-based single-channel MCG and its performance

  • Huiwu Wang
  • Hongsheng Ding
  • Lihua Zhang
  • Xuguang Huang
  • Weichang Chen
  • Ziqiang Wang
  • Ji Feng
  • Yiping Liu
  • Shiping Zhao
  • Yufeng Ren
  • Hongwei Yu
  • Fengzhi Xu
  • Xiaoyin Wang
  • Genghua Chen
  • Qiansheng Yang
Notes
  • 10 Downloads

Abstract

A single-channel high-Tc dc-SQUID magnetometer and gradiometer have been developed to record the magnetic field component perpendicular to the human chest generated by heart-beat. Magnetocardiogram (MCG) measurements have been carried out inside a magnetically shielded room. By sequentially adjusting a non-magnetic patient table with 5 cm pitch in X and Y directions, the field signals on a rectangle grid 5 × 5 over the chest area were registered in real time trace point by point with a typical dwell time over 30 cardiocycles each. Utilizing standard electrocardiogram (ECG) recordings as timing reference measured simultaneously with the MCG signals, the MCG data were then averaged and combined to form magnetic field patterns every 10 ms or so. Both the current dipole, which is parallel to MCG measuring plane and produces the vertical magnetic field, and its depth were determined as a function of time in a standard way. We have compared the MCG of healthy hearts with that of a heart with right bundle branch block. Significant differences between their MCGs have been observed.

Keywords

high-Tc dc-SQUID magnetocardiogram QRS complex 

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Copyright information

© Science in China Press 2002

Authors and Affiliations

  • Huiwu Wang
    • 1
  • Hongsheng Ding
    • 1
  • Lihua Zhang
    • 1
  • Xuguang Huang
    • 1
  • Weichang Chen
    • 2
  • Ziqiang Wang
    • 2
  • Ji Feng
    • 1
  • Yiping Liu
    • 1
  • Shiping Zhao
    • 1
  • Yufeng Ren
    • 1
  • Hongwei Yu
    • 1
  • Fengzhi Xu
    • 1
  • Xiaoyin Wang
    • 2
  • Genghua Chen
    • 1
  • Qiansheng Yang
    • 1
  1. 1.Institute of PhysicsChinese Academy of SciencesBeijingChina
  2. 2.China Japan Friendship Institute of Medical SciencesBeijingChina

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