Poincaré plot indexes of heart rate variability capture dynamic adaptations after haemodialysis in chronic renal failure patients

Abstract

The hypothesis that the Poincaré plot indexes of heart rate variability (HRV) detect dynamic changes after haemodialysis (HD) over the HRV in haemodynamically stable chronic renal failure (CRF) patients was examined. Minor axis (SD1), major axis (SD2) and the SD1/SD2 ratio were compared against standard HRV indexes in time and frequency domain, in a group of healthy subjects and in a group of CRF patients before and after HD. These indexes were estimated from Poincaré plots reconstructed with lags of one, two and four heartbeats. The surrogate data analysis technique was applied in order to discern if only random components or linear features of HRV contribute to its dynamics. None of the standard linear HRV indexes changed after HD. The Poincaré plot indexes measured from CRF patients were smaller than the ones measured from healthy subjects. In CRF patients the SD1/SD2 ratio decreased after HD, when a lag of four heartbeats was used (0.68 +/- 0.19 before HD versus 0.55 +/- 0.12 after HD, P<0.05). The presence of deterministic components in HRV were confirmed for all measures of the SD1/SD2 ratio. Moreover, a loss of non-linear components after HD was detected by the surrogate analysis over the SD1/SD2 ratio with a lag of four heartbeats. In conclusion, the SD1/SD2 ratio measured at lag of 4 heartbeats capture dynamic changes after HD upon the HRV of CRF patients that are not solely related to linear autocorrelations of HRV. This suggests that the SD1/SD2 ratio reflects non-linear information of HRV.

Nonlinear Methods to Assess Changes in Heart Rate Variability in Type 2 Diabetic Patients

“…The concept of this m lagged plot emerged from the recognition that any given R-R interval can influence up to eight subsequent R-R intervals 24,25 . It has been shown that SD1 correlates with the short-term variability of heart rate and is mainly influenced by parasympathetic modulation, whereas SD2 is a measure of long-term variability 14,26 and reflects sympathetic activation.…”

Phase space in EEG signals of women refferred to meditation clinic

“…The mean value of SD 1 for Poincare plot in Fz, Cz and Pz channels with two different lags (1)(2)(3)(4)(5)(6) are shown in Table 1. The values of SD 1 with lag 1 are about 1.53 -1.94, but they are at around 8.52 -10.95 with lag 6 in all channels.…”

“…The conventional plot has two dimensions and a lag of one interval, i.e., each point on the plot consists of a pair of successive intervals (RR i , RR i+1 ). Lerma et al [6] used longer lags (RR i , RR i+t with 1  t  8) to analyze HRV in chronic renal failure patients. Contreras et al [4] showed that lagged Poincare widths and spectral indices might be useful to distinguish normal from pathological heart rate signals.…”

Visual and Quantitative Analysis Methods of Respiratory Patterns for Respiratory Gated PET/CT

“…It has been often used to portray the dynamics of fluctuations between the intervals, such as in the studies of beat-to-beat heart rate variability [15–17]. We generated Poincaré sections by plotting the intersections of a given trajectory in the phase space diagram with a lower-dimensional state subspace, called the Poincaré plane, transverse to the trajectory [18, 19].…”