Research of simulation and application about the cardiac magnetic field

The physiological activity of the heart can not only form measurable electrical signals on the body surface, but also stimula te a weak magnetic field. An electromagnetic field calculation framework of human heart-torso model based on finite element method (FEM) was established. It is used to study the propagation process of cardiac electromagnetic field in the body. The three-dimensional model of human heart-torso was simplified geometrically. The heart was simplified as an ellipsoid of biventricular and the torso was an elliptical cylinder model. The electrical excitation conduction in the heart was studied by the improved FitzHugh-Nagumo (FHN) equation. Based on the finite element method, the transmembrane potential (TMP) distribution of the heart at different positions and at different times was obtained. Combined with the quasi-static Maxwell equations, the obtained transmembrane potential was converted into a current density, and the magnetic field distribution on the body surface was obtained. We supposed a new method of life detection based on the cardiac magnetic field.