Introduction. The new coronavirus infection (COVID-19) in children often occurs in a mild, moderate, or asymptomatic. After experiencing COVID-19, some children, as well as adults, had persistent symptoms over more than 12 weeks and could not be explained by alternative diagnoses. These changes are called Post-acute COVID-19 Syndrome (PACS, post-COVID-19 syndrome or post-covid syndrome). Clinical manifestations of post-covid syndrome in children are very diverse, there are combinations of autonomic, psycho-emotional, cognitive and somatic disorders, including disorders of the cardiovascular system.

Aim: analysis of changes in the functional state of the cardiovascular system in children in the post-covid period.

Materials and methods. The study included one hundred thirty one child aged of 5 to 17 years 11 months 29 days (mean age 12 years [9.5; 15]). The observed children were divided into 2 groups: group 1 (main) — children who had a mild new coronavirus infection (n = 76). The comparison group consisted of children who did not have COVID-19, suffered from acute respiratory viral infections of unspecified etiology of a mild course (n = 55). All children were analyzed for medical history, underwent clinical examination, electrocardiographic examination (ECG), echocardiographic examination (ECHO-KG), 24-hour Holter ECG monitoring and 24-hour blood pressure (BP) monitoring.

Results. Children who have had COVID-19 are significantly more often showed sinus tachycardia (p = 0.025), extrasystole (supraventricular, ventricular) (p = 0.046), atrioventricular blockade of the 2nd degree (p = 0.027) compared with children with ARVI. After undergoing COVID-19, in 19.7% of children an increase in blood pressure was detected, in 15.8% of children there was a significant decrease in blood pressure at night (p = 0.008). In 38.2% of children after COVID-19, there was a decrease in the activity of the parasympathetic division of the nervous system.

Conclusion. Children who have had a new mild coronavirus infection were shown to undergo a clinical examination with a mandatory assessment of blood pressure, heart rate and an ECG 3 and 6 months after the illness.

Contribution:Isaeva E.P. — concept and design of the study;Ponkratov D.A., Telesheva I.A., Gur’eva E.V. — collection and processing of the material;Zaitseva O.V., Lokshina E.E., Krutova A.V., Mukhortykh V.A., Kuznetsova E.V. — writing, editing the text.All co-authors — approval of the final version of the article, responsibility for the integrity of all parts of the article.

Acknowledgment. The study had no sponsorship.

Conflict of interest. The authors declare no conflict of interest.

Received: August 17, 2023Accepted: September 12, 2023Published: October 31, 2023