J. To et al., Evaluation of neurocardiac signals in pediatric patients with cyclic vomiting syndrome through power spectral analysis of heart rate variability, J PEDIAT, 135(3), 1999, pp. 363-366
Objective: To investigate autonomic regulation of neurocardiac signals in p
ediatric patients with cyclic vomiting syndrome (CVS).
Methods: Fourteen patients with CVS, ages 3 to 16 years, were screened to e
liminate any underlying cause for their symptoms, although 11 of the 14 pat
ients had a history of migraine in the immediate family Analysis of autonom
ic regulation was accomplished through power spectral analysis of the beat-
to-beat heart rate variability signal. Data from affected patients were com
pared with data from 38 control subjects, ages 5 to 16 years, by a one-way
analysis of variance. A measure of sympathovagal balance was obtained by co
mputing a ratio of power in the low-frequency band (0.02-0.15 Hz) to the po
wer in the high-frequency band (0.15-0.4 Hz).
Results: pediatric patients with CVS have an elevated sympathetic modulatio
n of the sinus node as represented by the low frequency/high frequency rati
o (1.45 +/- 0.42 in patients vs 0.89 +/- 0.29 in healthy control subjects,
P < .001).
Conclusions: The patients with CVS we studied have an autonomic imbalance w
ith enhanced sympathetic and diminished parasympathetic vagal modulation of
the heart.