[Non-invasive mapping of cardiac electric potential of a specific quasi-epicardium]

A procedure was proposed for non-invasive mapping of the cardiac electrical potential or a spherical quasiepicardium from its synchronous multichannel measurement on the surface of the chest, i.e. routine electrocardiodraphic mapping. Mathematical simulation was used to demonstrate that the quasiepicardial potential can be calculated with the accuracy sufficient for clinical diagnosis by applying the multipole electric field resolution method with allowance made for three lowest resolution terms. Due to the fact that the spherical quasiepicardium is more approximate to the heart and more concentric as to its center than the chest surface, the maps of the quasiepicardial potential permit recognition of some features of the pattern of a cardiac electric process, which do not manifest themselves in the distribution of the potential on the body's surface. The examples showing that the assessment of a cardiac abnormality can be made more accurate by using this method are given in the paper.