Compressed spectral arrays for the analysis of 24-hr heart rate variability signal: enhancement of parameters and data reduction.
Heart rate variability signal in the form of an R-R interval tachogram is detected in Holter type 24-hr ECG recordings. Spectral analysis is carried out over consecutive nonoverlapping records, and the information is displayed in the form of a compressed spectral array through parametric techniques. The trends of spectral parameters such as low-frequency (LF) and high-frequency (HF) powers and central frequencies are also plotted, together with the classical mean R-R value and variance relative to each single spectrum. These parameters quantify the effect of sympatho-vagal balance on heart rate control during the 24-hr period and provide important elements for the diagnostic evaluation of various pathologies, like hypertension. A spectral compression algorithm which checks the position of the poles relative to LF and HF bands inside the unitary circle in the complex zeta-plane is also developed. Applications of this procedure are foreseen in the clinical evaluation of ambulant patients as well as in the study of physical and psychological stress.
Cerutti
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Centro di Teoria dei Sistemi C.N.R., Dipartimento di Elettronica, Politecnico di Milano, Italy.
Bianchi
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Baselli
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Civardi
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Guzzetti
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S
Malliani
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Pagani
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A
Pagani
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M
D000465:Algorithms; D002940:Circadian Rhythm; D004562:Electrocardiography / Q000379:methods; D006339:Heart Rate; D006801:Humans; D006973:Hypertension / Q000503:physiopathology; D008991:Monitoring, Physiologic; D012815:Signal Processing, Computer-Assisted