I.V. Sokolova

ECG-diagnostics problem statement is considered for a functional myocardium state in a standard 12-lead system. It is shown that it is not an ECG-signal registered as an electric current from coupled electrodes without using the earth, but it is its first time derivative - a differential ECG. The use Wilson-s electrode, as a dispersive one, as well as cross-coupling occurring during ECG registration, present noises in a form of the sum of ECG of different leads as electric currents penetrating the whole body. Moreover, there is some incorrectness in the interpretation of genesis of ECG form elements that exists at present from the viewpoint of a «passive diastole». This theory takes into consideration only one phase of the active cardiac performance - a systolic (contractile) one providing for a delivery function as that of a hemodynamic pump. The existing approach to the analysis of information in ECG has purely empiric nature. It is based on an extensive research of a bioelectrical aspect of cardiac performance with the help of searching for one-to-one correspondence between ECG forms in 12-leads and various types of pathologies. However, they do not take into consideration the cardiac performance where the heart performs as a two-phase - delivery and suction - hemodynamic pump which presents the basis of an «active diastole» theory. Within the framework of this theory, there is suggested a new approach to diagnostic ECG analysis, including corresponding determination of the structure and mechanism of ECG-signal forming, which significantly extends and simplifies the understanding of ECG information.