Objective: Evaluation of the spectral parameters of heart rate variability at children with premature beats and mitral valve prolapse (MVP).
Methods: The study included 190 children: I group 160 (84.2%) children with premature supraventricular and ventricular beats and mitral valve prolapse, average age (13.32±0.23) years and II group, healthy children 30 (15.79%), average age (12.2±0.72) years, who were examined with ECG, ECOCG, ECG Holter monitoring over 24 hours, and ambulatory monitoring of blood pressure over 24 hours.
Results: Rhythm disorders: supraventricular prema-ture beats have been determined in 32 (16.84%) chil-dren, with prevails in the I group in 29 (18.12%) vs. 3 (10.0%) II group and ventricular premature beats in 12 (7.50%) only I group (p>0.05). Ambulatory ECG monitoring for 24 hours have been determined su-praventricular premature beats in 86.25% cases with MVP vs. 13.33% healthy children (p<0.001), ventricu-lar premature beats in 18.75% cases I group vs. 3.33% group (p<.05), sinus tachycardia in 75.50% children with MVP vs. 43.33% healthy children (p<0.001) and supraventricular tachycardia in 43.38% cases I group vs. 13.33% II group (p<0.001). Spectral parameters of the heart rate variability at children have been calcula-ted during 24 hours period and there were observed a prevalence of waves with low and very low frequency at children with MVP. Monitoring blood pressure over 24 hours has revealed, average values of systolic and dyas-tolic blood pressure day and night without statistical distinctions (p>0.05), the maximum pulse in the after-noon with the high average values at children with mi-tral valve prolapse: 120.93±2.79 b/min vs. 110.52±3.94 b/min in healthy children (p<0.05).
Conclusions: Results of the study showed that MVP are associated with supraventricular premature beats in 86.25% cases. Monitoring blood pressure over 24 ho-urs has revealed, average values of systolic and dyas-tolic blood pressure day and night without statistical distinctions between research groups. Analysis of the spectral parameters of the heart rate variability on ECG Holter monitoring over 24 hours, demonstrates preva-lence of waves with low and very low frequency at chil-dren with MVP, an autonomic imbalance characterized by sympathetic over activity.