Spectral decomposition of RR-variability obtained by an open loop parametric model for the diagnosis of neuromediate syncope

Author

Widesott, L. ; Nollo, G. ; Faes, L. ; Porta, A. ; Greco, M. Del ; Antolini, R.

Author_Institution

Dipt. di Fisica, Trento Univ., Italy

fYear

2001

fDate

2001

Firstpage

477

Lastpage

480

Abstract

The role of the cardiovascular regulatory mechanism in patients with neuromediate syncope (NS) is poorly understood. The aim of this study was to accomplish continuous non-invasive analysis of the baroreflex mechanism in patients during a head-tip tilt-table test (HTT) using an open-loop autoregressive model with exogenous input. The model describes the causal dependence of the RR interval on the systolic arterial pressure (SAP) variability. Thus, RR variability results as the linear composition of SAP-dependent (Pdep) and SAP-independent parts of the RR power (P). Further, the model allows the estimation of the baroreflex gain using the modulus of the transfer function (G) from SAP to RR in the low-frequency band. The results showed a significant decrease of both Pdep and G immediately before syncope. Thus, a reduced functionality of the baroreflex and of the sympathetic tone seemed to be the mechanism responsible for the NS event

Keywords

autoregressive processes; biocontrol; cardiovascular system; neurophysiology; parameter estimation; patient diagnosis; physiological models; spectral analysis; transfer functions; RR interval; RR power; RR variability; SAP-dependent part; SAP-independent part; baroreflex gain estimation; baroreflex mechanism; cardiovascular regulatory mechanism; causal dependence; consciousness loss; continuous noninvasive analysis; exogenous input; head-tip tilt-table test; low-frequency band; neuromediate syncope diagnosis; open-loop autoregressive model; open-loop parametric model; spectral decomposition; sympathetic tone; systolic arterial pressure variability; transfer function modulus; Baroreflex; Blood pressure; Cardiology; Frequency estimation; Heart rate variability; Medical treatment; Parametric statistics; Pathology; Spectral analysis; Testing;

fLanguage

English

Publisher

ieee

Conference_Titel

Computers in Cardiology 2001

Conference_Location

Rotterdam

ISSN

0276-6547

Print_ISBN

0-7803-7266-2

Type

conf

DOI

10.1109/CIC.2001.977696

Filename

977696