Kibern. vyčisl. teh., 2015, Issue 179, pp 70-80.
Najafian Toomajani Mohamadali, Junior Researcher of Medical Information Systems Department of the International Research and Training Center for Information Technologies and Systems of the National Academy of Sciences of Ukraine and Ministry of Education and Science of Ukraine, Glushkov ave., 40, Kiev, 03187, Ukraine, email: Najafian@mail.ru
Budnyk Mykola M., Dr (Engineering), Leading Researcher of Department of Sensor Instruments, Systems and Technologies of Non-Contact Diagnostics of the Glushkov Institute of Cybernetics of the National Academy of Sciences of Ukraine, Glushkov ave., 40, Kiev, 03187, Ukraine, email: firstname.lastname@example.org
Kovalenko Alexander S., Dr (Medicine), Prof., Head of Medical Information Systems Department of the International Research and Training Center for Information Technologies and Systems of the National Academy of Sciences of Ukraine and Ministry of Education and Science of Ukraine, Glushkov ave., 40, Kiev, 03187, Ukraine, e-mail: email@example.com
EVALUATION OF INHOMOGENEITY DEGREE OF ELECTRICAL PROCESSES INTO THE HEART VENTRICLES BASED ON MAGNETOCARDIOGRAPHY
Introduction. Methods for analysis of the current density distribution (CDD) maps as cross-sections of the human heart into the frontal plane were considered. Degrees of non-homogeneity of regional and global kinds are determined based on degree of difference between CDD maps and normal quasi-dipole map. Method for estimation of the abnormality degree of CDD maps caused by failures of electric processes into the heart ventricles has been proposed. Evaluation of regional and global inhomogeneity for each map is determined according to small, medium and large grades.
Purpose of the article is to assess the degree of abnormality of electrical processes in the ventricles of the heart through the MCG mapping, analysis of sets of CDD maps beginning of the QRS complex to the end of the T wave, the calculation of the degree of their differences from normal quasi-dipole map.
Methods. Method of assessing the degree of abnormality of the CDD maps.
Results. In order to achieve reliable classification of the degree of regional (global) maps inhomogeneity is assessed by a 3-point scale (small, medium, large), For a more detailed stratification of patients a total degree of inhomogeneity (abnormality) has developed on a 5-value scale: low (normal), below average (small abnormality), the average (intermediate abnormality), above average (mild abnormality), large (severe abnormality).
First determine the level of regional inhomogeneity. For each map, it is determined according to the 3-value scale – small, mild and severe degree.
Conclusion. This method can be applied to the analysis of not only CDD maps, but also for the magnetic field maps. In this case, it is needed to solve the inverse problem, and instead of the current areas, area of the extreme of the magnetic field were analyzed. However, the magnetic field gives a fairly indirect distribution pattern of excitation into the myocardium, so informative value is much lower for medical analysis.
In addition, method is preferable for using relatively cheap device, which allow make examination under normal condition without magnetically shielded room. Above factor greatly simplifies and reduces the cost of implementation of the MCG technology into clinical practice.
Keywords: current density distribution (CDD) map, estimation of regional inhomogeneity, estimation of global inhomogeneity.
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