PECULIARITIES OF ELECTROCARDIOGRAPHIC CHARACTERISTICS OF PRIMARY SCHOOLCHILDREN WITH DELAY OF MENTAL DEVELOPMENT

Abstract

Along with changes in the total body size in the body of young schoolchildren, there are
processes of intense anatomical growth of the heart and functional alterations in his work. The
economization of cardiac activity at this stage of ontogenesis is first and foremost related to the
change in tonic influences by the autonomic nervous system, which is reflected in bioelectric
processes occurring in the myocardium. The only way to study bioelectric phenomena in the
heart is electrocardiographic examination, which allows to detect abnormalities of both
functional and morphological nature.
Starting school is a powerful stress factor in a child's life. At this stage dramatically
changes the mode of employment and rest, there is a pronounced limitation of the motor activity
of the child, which is an important biological need of the human body. These factors potentiate
the development and contribute to the progression of diseases of the musculoskeletal system,
cardiovascular and other pathologists.
The article deals with the features of electrocardiographic characteristics of young schoolage children with mental retardation. The data obtained indicate that the major sex differences
in bioelectric processes of the heart in children with mental retardation (MR) are in the change
of electrical activity of the atria. Girls with MR have a shorter period of atrial systole in the
overall structure of the cardiocycle compared with boys. An analysis of the temporal parameters
of the electrocardiogram revealed that younger school-age children with MR, especially boys,
are characterized by a longer cardiac cycle. In the structure of the cardiocycle there is a
tendency to decrease the PQ interval, the QRS complex and the TP interval against the
background of the QT lengthening.
In addition to the temporal parameters of the electrocardiogram, an analysis of the
amplitude parameters that reflect the peculiarities of the electrical and metabolic processes in
the heart is important for the assessment of the functional state of the heart.