HEART RATE VARIABILITY IN THE ASSESSMENT OF ADAPTIVE CAPACITY IN NEWBORNS WITH PERINATAL INJURY OF CENTRAL NERVOUS SYSTEM

Relevance. The neurohumoral mechanisms regulating heart rhythm in newborns are a focal point of research in perinatal cardiology. This emphasis arises from the fact that heart rhythm serves as a key indicator of the functional interplay within the cardiovascular system and the overall physiological state of a newborn, acting as a primary marker of autonomic nervous system activity. Aim: To examine the characteristics of autonomic heart rhythm regulation in newborns with perinatal injuries of central nervous system through daily electrocardiogram monitoring. Subjects and methods. The study included 40 full-term newborns divided into two groups: Group I involved conditionally healthy newborns (n = 23), and Group II included newborns with hypoxic-ischemic lesions of the central nervous system (n = 17). Based on temporal and spectral analysis of heart rate variability, it was demonstrated that changes in the early neonatal period correlate with clinical signs of impaired postnatal adaptation. By the 3rd–4th day of life, all newborns exhibited a decrease in parasympathetic influence on heart rhythm and increased activity of the sympathetic division of the autonomic nervous system during the day. Hypoxic-ischemic injury of the central nervous system was associated with more pronounced autonomic dysfunction, leading to impaired regulation of the circulatory system. An imbalance between sympathetic and parasympathetic influences on the heart in newborns, who experienced asphyxia was identified as a significant arrhythmogenic factor. Heart rate variability emerges as a critical, informative marker for identifying at-risk newborns prone to developing heart rhythm disorders, facilitating timely inclusion in risk groups and ensuring appropriate follow-up care.