Ostapenko Y. Optimization of prevention of vascular disorders in children with connective tissue dysplasia and radiation-burdened anamnesis due to the Chernobyl accident

The dissertation is devoted to the complex study of vascular and biochemical disorders in children with connective tissue dysplasia (hypermobile syndrome,HMS), improvement of methods of instrumental and laboratory diagnostics, improvement of ways of prevention of cardiovascular system lesions in children with manifestations of HMS with radiation-burdened history to correct endothelial dysfunction. The peculiarities of clinical manifestations of HMS in children-descendants of liquidators and children are specified in the work from the zone of increased radiation control due to the accident at the Chernobyl nuclear power plant, the prevalence of cardiovascular disorders and its relationship with the presence of HMS, comorbidities, vitamin D prophylaxis was determined 3,8 times more often than children without clinical signs of HMS. The highest frequency of disorders of its functional state is observed in adolescents. Changes in lipid metabolism and endothelial dysfunction were assessed in children with and without signs of HMS. It was found that in children with HMS from the zone of increased radiation control there is a tendency to reduce the content of β-lipoproteins in the serum and significantly higher values of L-arginine and nitric oxide in the serum. It was determined that the most informative among biochemical markers of endothelial dysfunction in children with HMS is the content of nitric oxide in the serum. The parameters of the functional state of the heart and blood vessels are analyzed with the help of an innovative information-measuring complex of pulse-cardiac diagnostics. It is established that its use is a more informative method of preclinical diagnosis of the cardiovascular system, than the assessment of a standard electrocardiogram. It was determined that to detect and monitor endothelial dysfunction in children with HMS, it is sufficient to estimate the minimum number of its indicators (heart rate fluctuations, absolute spectral power of regulation, pulse wave amplitude and sphygmogram incision height). The relationship between the clinical manifestations of vascular disorders and indicators of endothelial dysfunction and lipid metabolism in groups of examined children, which are negatively changed in children with HMS. A more significant decrease in the content of vitamin D in children with HMS was determined. A prognostic scale for assessing significant anamnestic and clinical factors of increased risk of cardiovascular pathology in children has been developed. The effectiveness of correction of vascular disorders by vitamin D preparations in children with radiation-burdened anamnesis as a result of the Chernobyl accident with clinical signs of HMS was evaluated. An improved scheme for the prevention of vascular disorders in children with clinical signs of HMS has been developed. It has been proven that prescribing vitamin D to children with HMS promotes an increase in its content in the blood, reducing the incidence of clinical manifestations of cardiovascular disorders, while normalizing electrophysiological and biochemical markers of endothelial dysfunction.