Miklhalchuk O. Factors of myocardium systolic dysfunction formation in adolescents with arrhythmias

The thesis is devoted to the study of some factors which produce an impact on formation and development of myocardium systolic dysfunction in adolescents with arrhythmias by determining morphofunctional characters of the heart, cardiac rhythm variability (CRV), activity of neurohumoral systems (SAS and RAAS) , and proinflammatory cytokines findings. It was established that in adolescents with different variants of arrhythmias dysadaptable rearrangements of myocardium took place with concomitant aortal root dilatation, increased terminal systolic diameter and the LV volume, decreased pumping and contractile myocardial functions, as well as inadequate or paradoxical cardiac reaction on exercise. It was shown that myocardial pumping function decrease in adolescents with arrhythmias, irrespective of variant of cardiac rhythm disorders, was accompanied by certain increase in SAS or RAAS activity, activation of the proinflammatory cytiokines system and apoptosis factors, as well as CRV decrease. On the basis of regression analysis there were singled out some factors of myocardial systolic dysfunction development in adolescents with arrhythmias, and a regression model of arrhythmogenic cardiomyopathy formation was worked out. Key words: adolescents, arrhythmias, myocardium systolic dysfunction, neurohumoral systems, proinfammatory cytokines.