The noninvasive assessment of spontaneous temporal physiological parameters variations can provide valuable information about control systems involved in their complex regulations. Recently, in addition to conventional measures describing variability in time and frequency domains, methds based on nonlinear dynamics are increasingly used in physiology. The graphical analysis using Poincaré plot analysis with subsequent qualitative and quantitative analysis is one of them. The aim of this paper is to provide basic information about this method and its application in physiological research and clinical praxis.

        Key words: Poincaré plot, heart rate variability, nonlinear dynamics