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Measuring Cardiac Autonomic Nervous System (ANS) Activity in Children
09:45

Measuring Cardiac Autonomic Nervous System (ANS) Activity in Children

Published on: April 29, 2013

Cardiac autonomic modulation evaluated by heart interval variability is unaltered but subtly widespread in the

Dalmo Correia1, Luiz Fernando Junqueira, Rodrigo Juliano Molina

  • 1Faculty of Medicine of Triângulo Mineiro, Division of Tropical Medicine, Uberaba, MG, Brazil.

Pacing and Clinical Electrophysiology : PACE
|June 6, 2007
PubMed

Insights

Cardiac autonomic function in indeterminate Chagas' disease appears normal as a group, but individual variability in heart rate modulation exists. This suggests subtle autonomic nervous system changes in some patients.

Area of Science:

  • Cardiology
  • Autonomic Nervous System Function
  • Chagas' Disease Research

Background:

  • Cardiac autonomic function in chronic indeterminate Chagas' disease is poorly understood, with conflicting research findings.
  • This study aimed to clarify cardiac autonomic modulation in this patient group.

Purpose of the Study:

  • To analyze short-term heart interval variability in individuals with indeterminate Chagas' disease.
  • To assess cardiac autonomic modulation in a Brazilian endemic area.

Main Methods:

  • Collected 5-minute electrocardiogram (ECG) R-R interval data in supine and standing positions from 18 chagasic and 18 control subjects.
  • Analyzed time and frequency domain variability indices using the Mann-Whitney test.

Main Results:

  • Overall heart interval variability indices were statistically similar between chagasic and control groups.
  • A wide dispersion of individual variability indices was observed in the chagasic group, ranging from normal to altered levels.
  • This dispersion occurred in both supine and standing positions.

Conclusions:

  • Indeterminate Chagas' disease subjects, as a group, exhibit unchanged short-term heart interval variability.
  • Individual cardiac autonomic modulation varies significantly, with some showing depressed and others exacerbated indices.
  • This variability suggests that most chagasics lack significant lesions, while a minority may have subtle efferent innervation-sinus node complex damage.
Abstract

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