RESUMEN
AIM: To characterise cardiac rhythm dynamics in sleeping adolescents by heart rate trend in Holter monitoring (HM). MATERIALS AND METHODS: Synchroneous HM and classical night EEG-polygraphy from 22.00 to 08.00 were conducted in 9 healthy adolescents (5 boys and 4 girls) aged 10-15 years. The heart rate trends in sleep exhibited periods of stable rhythm (PSR) and periods of enhanced dispertion (PED) which took 38.4 and 61.6% of the sleep duration, respectively. PED occurred 5.3 +/- 0.16 times per night. The comparison of the heart rate trends to night sleep structure reflected at EEG indicated that fast sleep coincided with PED in 100% of cases being in the middle of PED cycle. PED incorporated also fragments I and II of slow wave sleep (SWS). PSR were represented primarily with phases II and IV of SWS. Step-by-step scanning of the right space of the interval histograms showed that maximal slowering of cardiac rhythm occurred in SWS phase II and fast sleep (76.5 and 23.5%, respectively). CONCLUSION: The profile of the heart rate night trend in HM reflects an independent ultradian rhythm. Maximal cardiac rhythm unstability and bradycardia occurred, respectively, in fast sleep and phase II of SWS.
Asunto(s)
Adolescente/fisiología , Electrocardiografía Ambulatoria , Frecuencia Cardíaca/fisiología , Sueño/fisiología , Arritmias Cardíacas/diagnóstico , Arritmias Cardíacas/fisiopatología , Niño , Femenino , Estudios de Seguimiento , Humanos , Masculino , Valores de ReferenciaRESUMEN
24-hour Holter monitoring of 60 healthy children aged 3 to 15 years provided criteria for assessing the circadian heart rate (HR) variations as a measure of alterations occurred in autonomic heart rhythm control. Specific HR dynamics during their sleep is described, which involves changes in steady-state rhythm and higher dispersion periods associated with the alternation of slow and fast sleep phases. Sex- and age-related HR features are defined during 24-hour monitoring.
Asunto(s)
Ritmo Circadiano , Electrocardiografía Ambulatoria , Frecuencia Cardíaca , Adolescente , Factores de Edad , Niño , Preescolar , Femenino , Humanos , MasculinoRESUMEN
A complex of methods including clinical analysis, ECG, and exercise EEG was used to examine 52 patients aged 2 to 20 years with Romano-Ward syndrome. There were two groups: group I with syncopal attacks, group II without them. The patients with Romano-Ward syndrome had dysfunction of the suprasegmental systems regulated autonomously in the form of functional insufficiency of the mesencephalic activating system. In the patients without syncopal attacks, there was hyperproduction of the theta-rhythm, which may reflect the mechanisms of compensation. According to the EEG readings, criteria for the syndrome gravity and sudden death risk factors were distinguished.