Abstract

Abstract A novel descriptor (Complex Correlation Measure (CCM)) for measuring the variability in the temporal structure of Poincaré plot has been developed to characterize or distinguish between Poincaré plots with similar shapes. This study was designed to assess the changes in temporal structure of the Poincaré plot using CCM during atropine infusion, 70 0 head-up tilt and scopolamine administration. The aim of this study was to asses the changes in temporal structure of the Poincaré plot using CCM during atropine infusion (parasympathetic blockade) and transdermal scopolamine patch administration (enhanced parasympathetic activity) phases. The change in CCM values during these autonomic perturbation phases revealed the physiological relevance of the new descriptor. The concordant reduction and enhancement in CCM values with parasympathetic activity indicates that the temporal variability of Poincaré plot is modulated by the parasympathetic activity which correlates with changes in CCM values. Introduction Heart rate variability (HRV) is one of the powerful noninvasive method for analyzing the function of the autonomic nervous system. It is useful to understand the interplay between the sympathetic and parasympathetic autonomic nervous system Poincaré plot is a visual presentation of time series signal to recognize the hidden patterns. It is also a quantitative technique in the sense that it has various parameters (ex: short-term variability (SD1) and long-term variability (SD2)) to quantify the information from the plot. The Poincaré plot of HRV signal is constructed by plotting consecutive points of RR interval time series (i.e., lag-1 plot). It is a representation of HRV signal on phase space or Cartesian plane In our previous study In this study, we demonstrate the physiological significance of the novel measure CCM by analyzing the effects of perturbations of autonomic function on Poincaré plot descriptors (SD1 and SD2) in young healthy subjects caused by the 70 0 head-up tilt test, atropine infusion and