Cardiovascular diseases occupy one of the leading places in the structure of neonatal morbidity. Pathogenesis of these disorders include impairment of regulation of the heart and blood vessels, which lead to destructive processes in the cells of the sinus node and other parts of the conduction system of the heart and changes in postnatal adaptation of the cardiovascular system. Diagnosis of arrhythmias requires in-depth study in infants, because them can be dangerous to the health of the newborn and lead to adverse consequences. Thus, the problem of arrhythmias and conduction in newborns is relevant and requires timely early diagnosis and further monitoring.
The study involved 187 newborns in the early neonatal period (the first 168 hours of life).
In-depth study included determination of copeptin and IMA levels in comparison with troponin I, electrophysiological, morphometric and hemodynamic parameters of cardiovascular system.
Assessment of daily ECG monitoring data revealed that the most common types of neonatal arrhythmias were tachyarrhythmias (p<0.05) and supraventricular arrhythmias (p<0.05). Comparison of the levels of copeptin and IMA in newborns with arrhythmias, showed significantly higher levels of IMA in newborns with cardiac arrhythmias (p<0.001), with the greatest myocardial damage in full-term infants, H = 27.5, p<0.001) and infants with asphyxia at birth (H = 25.3, p<0.001). Higher levels of copeptin were found in children with arrhythmias secondary to asphyxia (H = 27.3, p<0.0001).
Multiple regression analysis was used to determine probable correlations of copeptin in newborns with arrhythmias secondary to asphyxia with Apgar score at 1 minute, pH, platelets, calcium, P duration, TV1 amplitude, min RR (R = 0.770; R2 = 0.594; p<0.001); IMA with pCO2, BE, CPK-MB, SV6 amplitude (R = 0.812; R2 = 0.672; p<0.001); IMA in full-term infants with arrhythmias with TIII duration, dPDA, QTc (R = 0.902; R2 = 0.814; p = 0.006) and IMA in premature infants with arrhythmias with pCO2, P amplitude, LDH, copeptin (R = 0.770; R2 = 0.592 ; p <0.001). Diagnostic and prognostic indicators of neonatal arrhythmias are levels of copeptin > 0.1 ng/ml (AUC = 0.697; 95% CI [0.593–0.787]) and IMA > 2633.87 ng/ml (AUC = 0.732; 95% CI [0.631–0.818]), the level of IMA secondary to asphyxia of > 2279.96 ng/ml (AUC = 0,793; 95% СI [0,694–0,871]) is prognostic. The obtained results demonstrate the role of these biochemical markers of myocardial damage in the diagnosis of neonatal arrhythmias.
Daily ECG monitoring showed statistically significant differences in the indicators of myocardial electrical activity in newborns with arrhythmias with statistically higher values of average daily heart rate (p<0.05), maximum heart rate (p <0.05), lower values of minimum RR (p˂0, 01), higher values of maximum RR (p˂0.01) and higher QTc (p<0.01) in children of the main group, decreased HRV parameters. The risk of developing threatening ventricular arrhythmias in full-term infants, due to the impact on QTc, is associated with levels of AST, CPK, Na, EDDRV, d RA, TV1 and TV2 amplitude (R = 0.998; R2 = 0.997; p<0.00912 ). The state of sympathetic heart rate regulation (SDANN) in full-term infants depends to a greater extent on LDG and DBP levels (R = 0.739; R2 = 0.546; p<0.0006), in preterm infants - on the electrolyte state of umbilical cord blood and oxygen saturation (R = 0.632; R2 = 0.40; p<0.003). The condition of the parasympathetic HRV (rMSSD), which is phylogenetically immature in preterm infants, is influenced by the development of placental dysfunction (rbs = 0.3; p<0.05) and IAS aneurysm (rbs = 0.3; p<0.05); among the numerical variables - umbilical cord blood Ca, CRP, TV5 amplitude and TV1 duration (R = 0.618; R2 = 0.381; p<0.001).
Comparative analysis of Doppler echocardiography revealed that newborns with arrhythmias with asphyxia had higher rates of neonatal pulmonary hypertension (MW U Test: p1a, 1b<0.01; p1a, 2b<0.05) and a decrease in EDDLV (MW U Test: p1a, 1b<0,01), which leads to less efficient functioning and requires the involvement of compensatory mechanisms in the form of a positive chrono- and inotropic effect (MW U Test: p1a, 2b<0,01).
The study showed that statistically significant indicators of the prognosis of cardiac arrhythmias and conduction in newborns are the presence of asphyxia and parameters of adaptation at birth, levels of copeptin, troponin I, GGP, umbilical cord blood sodium, heart rate, QTc, amplitude of the R wave, ST segment status.
