Characteristics of ventricular extrasystoles co-occurring with comorbidities in young athletes

Abstract

Aim: to assess the role of autonomic disorders and undifferentiated connective tissue dysplasia (UCTD) of the heart in children with ventricular extrasystoles (VE) engaged in sports. Patients and Methods: the study included 52 athlete boys with newly diagnosed cardiac arrhythmia in the form of ventricular extrasystoles. The study group (n=34) consisted of children with moderate VE severity co-existing with asympaticotonic type of autonomic dysfunction syndrome (ADS) amid undifferentiated connective tissue dysplasia mostly affecting the heart (UCTDH). The study group was split into two subgroups: subgroup 1 (n=11) – children with monotopic VE persisting at load and subgroup 2 (n=23) – children with occasionally appearing VE which reduced in the vertical position and/or at load. The control group (n=18) consisted of children with moderate VE amid UCTDH without ADS manifestations. A comprehensive clinical and laboratory assessment was performed in all patients. Results: on Holter monitoring (HM), in patients of the study group, subgroup 1, a sinus rhythm was recorded with the presence of 9,000- 15,000 VE per day (single or paired). The power spectral analysis of heart rate variability (HRV) in the subgroup 1 children demonstrated that in most cases (10 (90.9%)) there were low levels of the total power (TP) (р<0.05) and high values of the high-frequency component (HF) (p<0.05) as compared to those in the control group children. Also, a significant decrease in creatine phosphokinase-MB activity in the blood serum was found in children of the study group, subgroup 1, as compared to the reference values (р<0.05). The VE development in the study group, subgroup1, children was caused by the combined exposure to sport loads and the autonomic control of cardiovascular function amid UCTDH. In the study group, subgroup 2, children the laboratory testing did not demonstrate any statistically significant changes in creatine phosphokinase-MB activity in the blood serum as compared to the reference values (р>0.05). On HM, in most of the subgroup 2 children, a sinus rhythm was recorded with the presence of 6,000-9,000 VE per day. The changes in HRV parameters and their spectrogram in 19 (82.6%) cases were common for asympaticotonic type. As compared to the values in the control group children, TP was slightly lower (р>0.05) along with a high HF level (р>0.05). A half of the control group children had a moderate increase in creatine phosphokinase-MB activity in the blood serum (р<0.05), while in other cases its values did not differ considerably from the normal range. On HM, in most cases a normal sinus rhythm with usually single EV, 300-5,000 per day, was recorded. The main measurements of the power spectral analysis of HRV and spectrogram indicators suggested that children of this group had sufficient body energy supply. The presence of VE in the control group children was associated with the impact of sport loads on the heart with dysplasia. Conclusion: the authors have distinguished the clinical variants of heart rhythm disorders in young athletes with different levels of body energy supply, VE patterns, etc. In young athletes, ventricular extrasystoles are characterized by a persisting occurrence in cases with asympaticotonic type of autonomic disorders amid UCTDH. They are associated with a decrease in energy supply of the body, in particular, the myocardial muscle. Occasionally occurring VE were recorded in athletes without significant disturbances in energy supply. KEYWORDS: ventricular extrasystoles, autonomic dysfunction syndrome, undifferentiated connective tissue dysplasia of the heart, energy supply, athletes. FOR CITATION: Cherkasov N.S., Doronina T.N., Prakhov A.V., Semenova I.A. Characteristics of ventricular extrasystoles co-occurring with comorbidities in young athletes. Russian Journal of Woman and Child Health. 2023;6(1):45–49 (in Russ.). DOI: 10.32364/2618-8430-2023-6-1-45-49.