Spectral analysis of fetal heart rate variability in fetuses with supraventricular extrasystoles

Fetal Diagn Ther. 2003 Jul-Aug;18(4):284-8. doi: 10.1159/000070811.


Objective: Fetal heart rate (FHR) variability is an important indicator of fetal well-being. In fetal tachyarrhythmias, however, visual analysis of FHR variability is limited. We therefore applied power spectral analysis of FHR to evaluate the fetal state.

Methods: Fetal R-R intervals were detected by means of an external ECG in 3 fetuses with supraventricular extrasystoles after cardiac malformations had been excluded by fetal echocardiography. Using an autoregressive model, power spectral densities were calculated from 20 consecutive 256-beat segments for the following frequency bands: <0.03 Hz (very low frequency), 0.03-0.069 Hz (low frequency; LF), 0.07-0.129 Hz (mid-frequency) and 0.13-1.0 Hz (high frequency; HF).

Results: The FHR variability in fetal supraventricular extrasystoles mainly resulted from the HF component (63.91 +/- 6.97%). The sympatho-vagal balance (LF/HF) was decreased in the tracings with extrasystoles (0.13).

Conclusion: The analysis of FHR variability in fetal supraventricular extrasystoles revealed an imbalance between sympathetic and parasympathetic regulation.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Electrocardiography / methods
  • Female
  • Fetal Diseases / diagnosis
  • Fetal Diseases / physiopathology*
  • Heart Rate, Fetal / physiology*
  • Humans
  • Infant, Newborn
  • Male
  • Pregnancy
  • Statistics, Nonparametric
  • Tachycardia, Supraventricular / diagnosis
  • Tachycardia, Supraventricular / physiopathology
  • Ventricular Premature Complexes / diagnosis
  • Ventricular Premature Complexes / physiopathology*