Specific features of electrocardiograms in infants with intrauterine growth restriction and developmental delays
Authors: Derevtsov Vitaly V. , Ivanov Dmitry O. , Shcherbakova Marina Yu. , Romanyuk Fedor P. , Chumakova Galina N. , Chistyakova Guzel N. 
Published: February 2022

Aim. Assessment of electrocardiographic indicators in infants born on time with delayed intrauterine growth and mild development.
Materials and methods. Under the supervision of 164 infants. From mothers with an aggravated somatic and obstetric-gynecological history, 139 children were born: 71 (gr. 1) with delayed intrauterine growth and development of mild severity, 68 (gr. 2) without delayed intrauterine growth and development. The control group (gr. 3) consisted of 25 practically healthy children born to practically healthy mothers. All children were born full-time. They were examined in dynamics at the age of 1 (n=154), 3 (n=142), 6 (n=133), 12 (n=130) months. A comprehensive analysis of the data of history, physical examination, electrocardiography was carried out. There was no medical intervention. The duration of the study is 3 years. Heart rate, incidence of early ventricular repolarization syndrome and nonspecific disorders of the repolarization process were evaluated; in the II standard retraction, morphology, amplitude in millimeters and width in seconds of the tooth P; duration in seconds of PQ interval (PR), QRS complex and QT interval; morphology, amplitude in millimeters of tooth T. Non-parametric methods of statistical analysis were used.
Results. The median amplitude of the tooth P on day 23 in children of subgr. 1b, compared with children of gr. 3, is 0.2 mm less; 1 month in children of gp. 1 (1b), compared with children of gp. 3, less by 0.1 mm; at 3 months in children of subgp. 1a, compared with children of subgp. 1b, less by 0.35 mm, in children of subgp. 1b, compared with children of gp. 3, more by 0.2 mm; at 6 months in children of gp. 1 (1a and 1b), compared with children of gr. 3, more by 0.2 mm; at 12 months in children of subgp. 1a, compared with children of subgp. 1b, less by 0.2 mm, in children of subgp. 1b, compared with children of gr. 2, more by 0.2 mm, in children of gp. 1 (1a), compared with children of gr. 3, less by 0.2 (0.5) mm, and, compared with children of gr. 3, less by 0.2 mm. From 3 to 6 months increased in children of subgp. 1a by 0.35 mm. In children of gp. 1st (1a), a slowdown from 23 days to 1 month of intradermal conduction by 0.01 s, from 1 to 3 months of intraventricular conduction by 0.01 s, from 3 to 6 months of intradermal conduction by 0.01 s. Electrical systole in children of gr. 1 slowed from 1 to 3 and from 3 to 6 months by 0.01 s; in children of subgp. 1a from 1 to 3 months increased by 0.01 s, from 3 to 6 months decreased by 0.01 s, from 6 to 12 months increased by 0.01 s. Median tooth amplitude T on 23 days, 1 month in children of gp. 1 (1a and 1b), compared to children of gr. 3, more by 0.4 mm and 0.3 mm, respectively; at 3 months in children of subgp. 1a, compared with children of subgp. 1b, less by 0.35 mm, and, compared with children of gr. 2, less by 0.2 mm, in children of subgp. 1b, compared with children of gr. 2 more by 0.15 mm, in children of gp. 1 (1b), compared with children of gr. 3, more by 0.3 (0.45) mm; at 12 months in children of subgp. 1b, compared with children of gr. 2, more by 0.4 mm, in children of gp. 1 (1a), compared with children of gp. 3, less by 0.3 mm. From 23 days to 1 month in children of gp. 1 (1a) increased by 0.8 mm.
Conclusion. Certain peculiarities of electrocardiogram in dynamics of growth and development of the organism of infants born on time with delay of intrauterine growth and development of mild severity related to volume overload of atrium, enlargement of interventricular septum, hypoxia, sympathetic activity, requiring corrective events are revealed.