Continuous monitoring of the sympatho-vagal balance through spectral analysis

The activity of the autonomic nervous system is noninvasively studied by means of autoregressive (AR) frequency analysis of the heart-rate variability (HRV) signal. Some methods of noise rejection and robustness for AR recursive identification are presented that make on-line frequency analysis of the heart-rate variability signal more reliable. The performance of the algorithms is first tested through simulations, and then results obtained on real data during ischemic episodes are presented.