New Cardiovascular Indices Based on a Nonlinear Spectral Analysis of Arterial Blood Pressure Waveforms

TL;DR

This paper introduces a nonlinear spectral analysis method based on the scattering transform to derive new cardiovascular indices from arterial blood pressure waveforms, providing insights into physiological states.

Contribution

It presents a novel nonlinear spectral analysis technique using the scattering transform to extract meaningful cardiovascular indices from blood pressure signals.

Findings

Effective decomposition of blood pressure waveforms into elementary components.

Successful application to tilt and handgrip tests showing promising results.

New indices contain relevant physiological information.

Abstract

A new method for analyzing arterial blood pressure is presented in this report. The technique is based on the scattering transform and consists in solving the spectral problem associated to a one-dimensional Schr\"odinger operator with a potential depending linearly upon the pressure. This potential is then expressed with the discrete spectrum which includes negative eigenvalues and corresponds to the interacting components of an N-soliton. The approach is similar to a nonlinear Fourier transform where the solitons play the role of sine and cosine components. The method provides new cardiovascular indices that seem to contain relevant physiological information. We first show how to use this approach to decompose the arterial blood pressure pulse into elementary waves and to reconstruct it or to separate its systolic and diastolic phases. Then we analyse the parameters computed from this technique in two physiological conditions, the head-up 60 degrees tilt test and the isometric handgrip test, widely used for studying short term cardiovascular control. Promising results are obtained.