When these lines are graphed sequentially they present a
wave portrait of heart rhythm (Fig. 2a). Rhythmographic representation
allows a great deal of information to be compressed in a simple picture.
The wave portrait in Fig. 2a is composed of 448 R-R intervals of the ECG.
A spectral analysis of this curve allows Nerve-Express to identify two
main spectral components (Fig. 2b):
- High frequency - 0.4 - 0.1 5Hz
- Low frequency - 0. 15 - 0.04 Hz
It has been found that there is a high correlation between the power of
High-frequency spectrum and the tone of the Parasympathetic Nervous System
(PSNS), and also between the power of Low -frequency spectrum and the tone
of the Sympathetic Nervous System (SNS). This finding has been well
documented in a number of medical and scientific publications and in
conference reports from the American College of Cardiology, the American
Heart Association, and others.
Nerve-Express uses a unique algorithm, which helps to analyse peak
amplitudes in both high and low spectral frequencies and to graph the
quantitative relationship between activities of the Sympathetic and the
a) Wave 'portrait' of Heart Rate Variability
b) Spectral Function
of Heart Rate Variability
[Top of Page]
[ANSA Table of Contents] [ Back ] [ Up ] [ Next ]