[Development of 64-channel magnetocardiography and clinical application]

A magnetocardiogram (MCG) can detect three-dimensional electric phenomena of the heart, because MCG does not influence the lung and torso form of the internal organs. In this symposium, we report the application of 64-channel MCG for the measurement of various arrhythmias (atrial flutter, atrial fibrillation), myocardial injury, and fetus arrhythmia. We composed function images of the conduction wave front and injured myocardium superimposed on a three-dimensional heart outline from the magnetic field. The injured myocardium was determined by a three-dimensional RT dispersion map. This algorithm allows the non-invasive determination of the space location of signal source and injured myocardium. In addition, 64-channel MCG can detect the fetal arrhythmias and autonomic nervous activity, which allows the diagnosis of fetus arrhythmia in detail before birth. Thus, MCG measurement is a useful non-invasive diagnostics procedure. However, there are several problems such as sealed room installation and the use of liquid helium. In the future, a newer technology that does not require liquid helium and a sealed room will be necessory.