Simulation of MCG signal in 2D cardiac tissue sheet with ischemic condition

Magneto cardiogram (MCG) is a noninvasive and noncontact technology for measuring weak magnetic signals generated by cardiac electrical activities, which are possible to become a routine tool for clinical diagnosis of cardiac disease. The relationship between excitation propagation in 2D cardiac tissue sheet and MCG signal has not been well investigated yet. In this paper, the simulations were performed on a 2-D 1.0cm × 1.0cm cardiac tissue sheet with and without ischemia condition. Ten Tusscher´s human ventricular cell model was used as the basic unit, and with some modifications in order to get lower computation expense. The electrical properties caused by ischemia were realized by raising external potassium concentrations from 4.5 mM to 10 mM and adding ATP-sensitive K⁺ (K_ATP) current. The mono-domain equation was used to simulate the excitation propagation, and the MCG/Electrocardiography (ECG) signals were calculated using the boundary element method. The simulation results showed that the MCG signal is more sensitive to identify myocardial ischemia than the ECG signal, and thus suggest that the MCG would be a useful tool for cardiovascular disease research.