Evaluation of currents induced in the heart as a consequence of standing in strong static magnetic field

  • Danilo Mureddu Freelance Engineer, Via Celestini, 1 - 40037 Pontecchio Marconi (BO), Italy; cell. ++39 329 2932188, e-mail: danilo.mureddu@gmail.com
  • Simona Valbonesi Consorzio Elettra 2000, Pontecchio Marconi, Bologna
  • Ermanno Papotti University of Parma, Health Physics Department, Parma
  • Andrea Vanore Prevention and Protection Department, Arcispedale Santa Maria Nuova, Reggio Emilia
  • Marina Barbiroli Bologna University, Electrical, Electronic and Information Engineering Department “Guglielmo Marconi”, Bologna
Keywords: MRI, magnetic static field, induced current, heart


In the last few years we have been watching a remarkable development of technologies using high density static magnetic
fields in industry and medicine. In medical environment the diagnostic use of Magnetic Resonance (MR) has become
the Gold Standard to identify a great number of pathologies. The increase of static magnetic field intensity levels,
besides the equipment resolution’s gain and the application fields widening, has led to a substantial decrease of clinical
examination duration with economic benefits and better comforts for the patient. On the other hand we have witnessed
an increase of problems connected with the exposure to high density static magnetic fields. This work focuses
on the research of a model thought to evaluate currents induced within the heart, as a consequence of the exposure to
the static magnetic field produced by a Magnetic Resonance scanner; such induced currents, when too high, could have
negative effects on heart’s electric conduction. Starting from a simplified modelling of the heart and making detailed
measurements of the static magnetic field, we propose a mathematical model for the evaluation of electric currents induced
within the heart by static magnetic field, as a consequence of the blood flowing within the arteries and within the
heart chambers. Such currents, provoked only by the standing of a patient in a strong static magnetic field, are not avoidable
and could be the cause of some heart problems described in medical literature and denounced by patients exposed
to static fields above 7.0 T, for diagnostic reasons. Moreover the heart is extremely sensitive to external currents, so
currents induced at an intensity higher than physiological levels could cause malfunctions to the electrical conduction
of the organ.


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