title: Evaluation of neurocardiac signals in pediatric patients with cyclic vomiting syndrome through power spectral analysis of heart rate variability.
abstract: OBJECTIVE
  To investigate autonomic regulation of neurocardiac signals in pediatric patients with cyclic vomiting syndrome (CVS).
  
  
  METHODS
  Fourteen patients with CVS, ages 3 to 16 years, were screened to eliminate any underlying cause for their symptoms, although 11 of the 14 patients had a history of migraine in the immediate family. Analysis of autonomic regulation was accomplished through power spectral analysis of the beat-to-beat heart rate variability signal. Data from affected patients were compared 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 computing a ratio of power in the low-frequency band (0. 02-0.15 Hz) to the power in the high-frequency band (0.15-0.4 Hz).
  
  
  RESULTS
  Pediatric patients with CVS have an elevated sympathetic modulation of the sinus node as represented by the low frequency/high frequency ratio (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 with enhanced sympathetic and diminished parasympathetic vagal modulation of the heart.
authors.affiliation: Division of Pediatrics, Children's Hospital, Hamilton Health Sciences Corporation and McMaster University, Hamilton, Ontario, Canada.
authors.forename: J
authors.initials: J
authors.lastname: To
authors.forename: R M
authors.initials: RM
authors.lastname: Issenman
authors.forename: M V
authors.initials: MV
authors.lastname: Kamath
mesh_terms: D000293:Adolescent; D000704:Analysis of Variance; D001342:Autonomic Nervous System Diseases / Q000150:complications* / Q000175:diagnosis* / Q000503:physiopathology; D016022:Case-Control Studies; D002648:Child; D002675:Child, Preschool; D004562:Electrocardiography / Q000379:methods*; D005260:Female; D006339:Heart Rate; D006801:Humans; D008297:Male; D008403:Mass Screening; D008881:Migraine Disorders / Q000209:etiology; D010507:Periodicity; D015203:Reproducibility of Results; D012119:Respiration; D012815:Signal Processing, Computer-Assisted; D013577:Syndrome; D014630:Vagus Nerve / Q000503:physiopathology; D014839:Vomiting / Q000209:etiology*