Boundary element method formulation and its solution in forward problem of electrocardiography by using a realistic torso model

Kurt, Arda
The electrical currents generated in the heart propagate to the outward direction of the body by means of conductive tissues and these currents yield a potential distribution on the body surface. This potential distribution is recorded and analyzed by a tool called electrocardiogram. It is not a problem, if this process continues normally; however, when it is distorted by some abnormalities, the results will be fatal. Electrocardiography (ECG) is the technique dealing with the acquisition and interpretation of the electrical potentials recorded at the body surface due to the electrical activity of the heart. This can be realized by using one of the two approaches utilized in ECG namely; forward and inverse problems. The former one entails the calculation potentials on the body surface from known electrical activity of the heart and the latter one does the reverse. In this thesis, we will construct the body surface potentials in a realistic torso model starting from the epicardial potentials. In order to solve the forward problem, one needs a geometric model that includes the torso and the heart surfaces, as well as the intermediate surfaces or the intervening volume, and some assumptions about the electrical conductivity inside the enclosed volume. A realistic torso model has a complex geometry and this complexity makes it impossible to solve the forward problem analytically. In this study, Boundary Element Method (BEM) will be applied to solve the forward problem numerically. Furthermore, the effect of torso inhomogeneities such as lungs, muscles and skin to the body surface potentials will be analyzed numerically.


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Citation Formats
A. Kurt, “Boundary element method formulation and its solution in forward problem of electrocardiography by using a realistic torso model,” M.S. - Master of Science, Middle East Technical University, 2006.