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The ventricular late potentials in children with vasodepressor response of vasovagal syncope

Runmei Zou1, Yunli Li1, Lijia Wu1

  • 1Department of Pediatric Cardiovasology, Children's Medical Center, The Second Xiangya Hospital, Central South University; Institute of Pediatrics, Central South University, Changsha, Hunan, 410011, China.

International Journal of Cardiology
|July 9, 2016
PubMed

Insights

Ventricular late potentials (VLPs) show prolonged durations in children with vasovagal syncope (VVS-V), particularly LAS40, despite similar prevalence. These findings suggest subtle electrical changes in VVS-V patients.

Area of Science:

  • Cardiology
  • Pediatric Electrophysiology

Background:

  • Vasodepressor response of vasovagal syncope (VVS-V) is common in children.
  • Ventricular late potentials (VLPs) are potential markers of cardiac electrical instability.

Purpose of the Study:

  • To investigate the characteristics of VLPs in children diagnosed with VVS-V.
  • To compare VLP parameters between children with VVS-V and healthy controls.

Main Methods:

  • Signal-averaged electrocardiogram (SAECG) was used to measure VLPs.
  • 184 children with VVS-V (diagnosed via head-up tilt test) and 105 healthy controls were analyzed.

Main Results:

  • Heart rate was slightly decreased in the VVS-V group.
  • While VLP prevalence was similar, durations of TQRS, RMS40, and LAS40 were significantly prolonged in the VVS-V group.
  • Abnormal prolonged LAS40 was more frequent in children with VVS-V.

Conclusions:

  • Children with VVS-V exhibit prolonged ventricular repolarization parameters (TQRS, RMS40, LAS40) compared to healthy individuals.
  • The increased proportion of abnormal LAS40 in VVS-V patients suggests potential subtle cardiac electrical abnormalities.
Abstract

Keywords:
Head-up tilt testVasodepressor responseVasovagal syncopeVentricular late potentials

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