Solving the forward problem in electrocardiography: analysing the selection of appropriate regions of impedance models

This study deals with the forward problem in electrocardiography, which consists of computing the electrical potential distribution in the human body due to cardiac sources. Thereby, an important task is the selection of appropriate models, because their properties determine the quality and costs of the solution of the forward problem. Subject of this study is an examination, which regions of the body should be included in impedance models. Therefore, different impedance models, varying in position and size, are examined. They were derived from a realistically shaped, highly detailed anatomical model. The model originates from tomographies of the Visible Man dataset, National Library of Medicine, Bethesda, Maryland (USA), using techniques of digital image processing. The examination is carried out by analysis and comparison of computed body surface potential maps, which are numerically calculated based on a set of different models using the finite difference method