Mathematical biomarkers for autonomic regulation of cardiovascular system

Abstract

Blood pressure and heart rate are the most important vital signs in diagnosing disease. Both blood pressure and heart rate are characterized by a high degree of variability short term from moment to moment, medium term over the normal day and night as well as in the very long term over months to years. The study of new mathematical algorithms to evaluate the variability of cardiovascular parameters has a high potential in the development of new methods for early detection of cardiovascular disease, to establish differential diagnosis with possible therapeutic consequences. The autonomic nervous system is a major player in the general adaptive reaction to stress and disease. The quantitative prediction of the autonomic interactions in multiple control loops pathways of cardiovascular system is directly applicable to clinical situations. The primary objective of this project is to develop new multimodal analytical techniques for the variability of cardiovascular system. We will focus on new approaches for deterministic parameter identification. For this, we will study the effects of several drugs blocking the autonomic system at specific levels and study their effects on arterial pressure and heart rate variability. A multimodal analysis of cardiovascular signals will be studied by evaluating their amplitudes, phases, time domain patterns and sensitivity to imposed stimuli, i.e.: drugs blocking the autonomic system. The causal effects, gains and dynamic relationships will be studied through dynamical fuzzy logic models, such as the discrete-time model and discrete-event model. We expect an increase in accuracy of modeling and a better estimation of the heart rate and blood pressure time series, which could be of benefit for intelligent patient monitoring. We foresee that identifying quantitative mathematical biomarkers for autonomic nervous system will allow individual therapy adjustments to aim at the most favorable sympathetic-parasympathetic balance. (AU)