PECULIARITIES OF ENTROPY-PARAMETRIC INVESTIGATION OF INTERMEDIARY INTERVALS
OF ELECTRIC CARDIO SIGNAL 

Polosin Vitaly Germanovich, candidate of technical sciences, associate professor, sub-department of physics, Penza State University,
E-mail: polosin-vitalij@yandex.ru 

53.082.9: 612.172.4 

Background. The introduction of mobile information technologies has formed prerequisites for improving the algorithms of medical diagnostic equipment. The subject of the study are methods for determining diagnostic significant intervals of the electrocardiogram
(ECS). The aim of the paper is to investigate the possibilities of informationand-probabilistic technologies for the analysis of the ECS.
Materials and methods. The paper deals with a qualitatively new approach to the processing and analysis of ECS, according to which the study of the ECS intervals is based on a change in the activity of cardiomyocytes depending on the phase of development of the action potential and is based on the dependence of both the derivatives of the ECS change and on the information entropy
of the ECS values on the thermodynamic activity of the heart tissues also.
Results. On the basis of probabilistic and information uncertainty of ECS values, QRS-complex detectors were constructed, which contain additional possibilities for estimating the position of the maximum R of the tooth and, as a consequence, determining the RR-intervals of the ECS that is necessary for determining the heart rate and for examining the variability of the heart rhythm. The realization of the sum operator of the second and third derivatives in the construction of the QRS-complex detectors and ECS wave is based on the control of the time dependence of the sum for central moments of the third and fourth order central moments
calculated for the selection of the values of the ECS in the sliding window. The non-linear dependence of high-order moments on the differences between the values in the sliding window provides a reliable detection of the QRS-complex and ECS wave.
Conclusions. Universal tools were developed to detect different epochs of the cardio cycle thanks to joint studies of information and probabilistic properties of the electrocardiogram. The use of connexion for of information and probabilistic uncertainties in the values of the EKS of the sliding time window adds qualitatively new possibilities to the structure of the monitoring system at the stage of registration of the EKS. 

information-probabilistic approach, entropy, uncertainty of values, moments of the third and fourth order, wave of the electric cardiac signal