Ukraine, Zaporizhzhia, 2026.
The dissertation is devoted to optimizing the diagnosis and monitoring of cardiovascular disorders in children aged 5–12 years with post-COVID syndrome based on the study of the clinical features of multisystem inflammatory syndrome and the assessment of changes in laboratory and instrumental parameters.
The study presents the results of examination of 80 children in the main group with post-COVID syndrome, who were divided into subgroups according to disease severity based on the diagnostic criteria for multisystem inflammatory syndrome: 25 children were included in subgroup I and 55 children in subgroup II. The control group consisted of 30 apparently healthy age-matched children.
The clinical examination of children with post-COVID syndrome demonstrated that this category of patients was characterized by a multisystem pattern of clinical manifestations involving general infectious, respiratory, gastrointestinal, nervous, and cardiovascular systems. The most frequent clinical symptoms in the main group were fever, recorded in 96.3% of cases, sleep disturbances in 65.0%, dyspnea in 65.0%, abdominal pain in 58.75%, decreased concentration in 57.5%, headache in 51.25%, cough in 48.75%, and nausea in 46.25% of children. It was found that the structure of post-COVID syndrome was dominated by a moderate course, diagnosed in 68.75% of children, whereas a severe course was established in 31.25% of cases, indicating the clinical heterogeneity of the condition under study.
Scientific novelty of the study. By means of comprehensive examination, the frequency and severity of cardiovascular manifestations in children with post-COVID syndrome were determined. A statistically significant relationship was established between the severity of the prior disease and the levels of inflammatory markers, as well as the degree of cardiovascular involvement. Scientific data on the course of post-COVID syndrome in children aged 5–12 years were expanded through detailed study of organ and system involvement, including the cardiovascular system. Changes in echocardiographic parameters in children with post-COVID syndrome were studied in greater detail. The alterations in the specific marker of cardiomyocyte injury, NT-proBNP, and the marker of coagulation system impairment, D-dimer, were further elucidated. The patterns, spectrum, and feasibility of prolonged follow-up of children with post-COVID syndrome were established. Recommendations were developed for the management of children with identified manifestations of cardiovascular dysfunction in order to improve the general condition of children with post-COVID syndrome.
Practical significance of the obtained results. In order to improve the diagnosis of long-term consequences of coronavirus infection caused by SARS-CoV-2 in pediatric patients, an optimized diagnostic algorithm based on laboratory and instrumental methods for assessment of the cardiovascular system was proposed. Clinical variants of post-COVID syndrome in children aged 5–12 years were identified.
A method for predicting the development of severe post-COVID syndrome with cardiovascular involvement in children aged 5–12 years was developed using receiver operating characteristic curves based on disease severity indicators, speckle-tracking echocardiographic parameters, D-dimer and NT-proBNP levels, and IgG to SARS-CoV-2. An algorithm for follow-up of patients aged 5–12 years with post-COVID syndrome was created and implemented.
