Time-frequency analysis of the EGG in the diagnosis of vasovagal syndrome in older people
Journal
Annual International Conference of the IEEE Engineering in Medicine and Biology - Proceedings
Journal Volume
26 I
Pages
290-293
Date Issued
2004
Author(s)
Abstract
The Smoothed Pseudo Wigner-Ville Distribution (SPWVD) is used for the time-frequency analysis of variations in RR interval. A novel technique to determine the smoothing window lengths is implemented, and a new heart rate variability (HRV) metric is developed, instantaneous center frequency variability (ICFV), which uses the time-frequency map generated by the SPWVD. The technique is then applied to 50 patients with unexplained falls and age > 60, under-going head-upright tilt table testing (HUT). Eighteen of the patients were diagnosed with vasovagal syndrome. Attempts at syncope prediction using the new metric is an improvement on traditional techniques: an ICFV less than 0.07 Hz from 90 s to 180 s after tilt is predictive of a negative test (negative predictive value: 0.77). The comorbidity and autonomie degeneration present in elderly patients are thought to be responsible for lowering the negative predictive value.
Subjects
Blood vessel prostheses
Cardiovascular system
Electrocardiography
Frequency domain analysis
Neurology
Time domain analysis
Heart rate variability (HRV)
Vasovagal syncopes
Vasovagal syndromes
Biomedical engineering
Type
conference paper