Device Measures Magnetic Field of Heart, Providing a New Tool to Diagnose The Organ

Besides commonly observed electric fields, the heart also produces magnetic fields that have their own signatures pinpointing cardiac conditions like ischemia. Though magnetometers have existed for over a hundred years, detecting weak magnetic signals in a magnetically noisy environment is difficult. Scientists at the University of Leeds, while working on quantum mechanical experiment, developed a magnetometer that may serve as a model for a new diagnostic modality.

Large scale magnetometers have been used for some time for things like directional drilling for oil and gas, on spacecraft for planet exploration and to detect archaeological sites and locate other buried or submerged objects. What has prevented them being used for identifying heart conditions is their size and high cost along with the specialist skill needed to operate them. Using them to examine a patient would involve containing the person within a magnetic shield to cut out other electrical interference.
Professor Ben Varcoe, who is leading the research team at Leeds, said: “The new system gets round previous difficulties by putting the actual detector in its own magnetic shield. The sensor placed over the area being examined lives outside the shielded area and transmits signals into the detector.
“The sensor head is made up of a series of coils that cancel out unwanted signals and amplifies the signals that are needed. So the tiny magnetic fields produced by a person’s heart can be transmitted into the heavily shielded environment. What we’ve been able to do is combine existing technology from the areas of atomic physics and medical physics in a completely unique way.”
Like all parts of the body, the heart produces its own distinctive magnetic ‘signature’. The research team has demonstrated that their magnetometer – developed as part of their work in the area of quantum physics – can reveal tiny variations in that signature. Studying these variations can, in turn, reveal the presence of a cardiac condition. The team is now working on miniaturising the magnetometer for widespread medical use. The device could be ready for use in routine diagnosis in around three years.