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.
Centro di Teoria dei Sistemi C.N.R., Dipartimento di Elettronica, Politecnico di Milano, Italy.
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Cerutti
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Bianchi
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Baselli
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Civardi
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Guzzetti
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Malliani
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Pagani
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Pagani
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