FUNCTIONAL CONDITION OF THE CARDIOVASCULAR SYSTEM IN CHILDREN WITH TYPE 1 DIABETES DEPENDING ON THE LEVEL OF GLYCEMIA

Abstract

Purpose of the study: to determine main parameters of the heart rhythm in children with type 1 diabetes, depending on the night level of glycemia. We performed bifunctional monitoring of glycemia and ECG in 50 patients with type 1 diabetes from 10 to 17 years. Depending on the glycemic parameters summarized in all patients we divided 3 groups: Group 1 (n=11) – sites of hypoglycemia (≤3.9 mmol/l), Group 2 (n=35) – optimal level of glycemia (4.0-9.0 mmol/l) and Group 3 (n=45) – sites of hyperglycemia (> 9 mmol/l). According to the results of glycemic monitoring, 96% of children do not have glycemic target marks at night and 20% of patients have asymptomatic night hypoglycemia. When analyzing the parameters of Holter ECG monitoring, the greatest value of heart rate, duration of the QTc interval, as well as atrial ectopic activity were often recorded during periods of hypoglycemia. Hyperglycemia also causes pathologic elongation of the ventricular electric systole and a greater number of ventricular extrasystoles. Thus, night hypo- and hyperglycemia in children and adolescents with type 1 diabetes leads to an extension of the QTc interval, an increase in the number of extrasystoles with the highest severity and frequency in hypoglycemia. We noted a high level of functioning of the sympathetic department of the autonomic nervous system and the central contour of heart rhythm regulation in children and adolescents with type 1 diabetes mellitus in hypoglycemia.