Ventricular late potentials in schoolchildren with type I diabetes mellitus

Purpose — to study the indicators characterizing the ventricular late potentials (VLP) in schoolchildren with type I diabetes mellitus (TIDM). Materials and methods. 120 children aged 6–17 years were examined (56 — primary school age (6–11 years old), 64 children — senior school age (12–17 years old)). Of which at the age of 6–11 years old: 36 — with TIDM main group I, 20 healthy children (control group I). Of children 12–17 years old, 44 children were with TIDM — main group II, 20 healthy children were included in the control group II. In each age main group рatients with TIDM were divided into 2 subgroups depending on the duration of the disease: subgroup A — 39 patients (22 — primary school age, 17 — senior school age) with diabetes duration 1–3 years and subgroup B — 41 patients (14 и 27 retrospectively) with diabetes duration 4 years or more. All children underwent registration of VLP by high$resolution ECG. The following parameters were calculated: duration of the filtered QRS complex (TotORS, ms), the duration of the low$amplitude (up to 40 μV) part of the signal at the end of the QRS complex (LAS40, ms), the rms amplitude of oscillations in the last 40 ms of the ORS complex (RMS40, μV), as well as the ratio TotQRS / RMS40. The obtained results were processed on the basis of Microsoft Office Excel 2007 spreadsheets using the Statistica 7.0 package for Windows. Results. When analyzing the indicators, it was found that children with diabetes in comparison with healthy children had differences that could be interpreted as signs of lifespan (increase in TotORS, LAS40 and TotQRS / RMS40 ratio, decrease in RMS40 values). Such changes with varying degrees of reliability were recorded in all age groups, and were more pronounced in subgroups B, both in children 6–11 years old, and in patients 12–17 years old. This speaks in favor of the aggravation of the disturbance in the electrical stability of the myocardium as the duration of the disease increases. Conclusions. Thus, the data obtained indicate that children with type I diabetes have foci of delayed fragmented activity due to the electrophysiological heterogeneity of the myocardium. The presence of such foci is recognized as an independent prognostic factor for the risk of fatal arrhythmias, which poses the task of the specialists involved in the management of these patients with the early detection of VLP in order to prevent life$threatening conditions. The research was carried out in accordance with the principles of the Helsinki Declaration. The study protocol was approved by the Local ethics committee of all participating institutions. The informed consent of the patient was obtained for conducting the studies. No conflict of interest was declared by the authors.