Poincaré plot indexes of heart rate variability detect dynamic autonomic modulation during general anesthesia induction.

Beat-to-beat heart rate variability (HRV) is caused by the fluctuating balance of sympathetic and parasympathetic tone. The Poincaré plot has been used to evaluate HRV. In this study, we validate that this new method may qualitatively and quantitatively assess the sympathovagal fluctuation in patients during induction of anesthesia with sevoflurane. Twenty-eight young patients were allocated for the study. The patients received a tilt test and on the next day they sustained anesthesia induced with inhaled anesthetics. Electrocardiography signals from the patients were relayed to an analogue-digital converter. The Poincaré plot is quantified by measuring SD1, SD2, and SD1/SD2. Power spectral analyses were performed and LF, HF and HF/LF were calculated. The LF power and the SD2 of the Poincaré plot increased while subjects were tilt-up from the supine position. Additionally, a significant correlation were found between LF and SD2, HF and SD1 (p < 0.05), and LF/HF and SD2/SD1 (p < 0.01). Sevoflurane inhalation for 10 minutes had no effect on heart rate, but diminished LF, total power and SD1, SD2 of the Poincaré plot respectively. However, the LF, SD2 and LF/HF increased; the HF, SD1 and SD1/SD2 ratio decreased after intubation stimulation. Poincaré plot and power spectral analysis of HRV during tilt test and sevoflurane induction significantly correlate. Poincaré plot analysis is easier and more sensitive at evaluating the sympathovagal balance and observing the beat-to-beat HRV.

Hsu CH ，Tsai MY ，Huang GS ，Lin TC ，Chen KP ，Ho ST ，Shyu LY ，Li CY ... -  《-》

Correlations between the Poincaré plot and conventional heart rate variability parameters assessed during paced breathing.

Guzik P ，Piskorski J ，Krauze T ，Schneider R ，Wesseling KH ，Wykretowicz A ，Wysocki H ... -  《Journal of Physiological Sciences》

Poincaré plot indexes of heart rate variability: relationships with other nonlinear variables.

The Poincaré plot for heart rate variability analysis is a technique considered geometrical and non-linear, that can be used to assess the dynamics of heart rate variability by a representation of the values of each pair of R-R intervals into a simplified phase space that describes the system's evolution. The aim of the present study was to verify if there is some correlation between SD1, SD2 and SD1/SD2 ratio and heart rate variability nonlinear indexes either in disease or healthy conditions. 114 patients with arterial coronary disease and 65 healthy subjects underwent 30 minute heart rate registration, in supine position and the analyzed indexes were as follows: SD1, SD2, SD1/SD2, Sample Entropy, Lyapunov Exponent, Hurst Exponent, Correlation Dimension, Detrended Fluctuation Analysis, SDNN, RMSSD, LF, HF and LF/HF ratio. Correlation coefficients between SD1, SD2 and SD1/SD2 indexes and the other variables were tested by the Spearman rank correlation test and a regression analysis. We verified high correlation between SD1/SD2 index and HE and DFA (α1) in both groups, suggesting that this ratio can be used as a surrogate variable.

Hoshi RA ，Pastre CM ，Vanderlei LC ，Godoy MF ... -  《-》

Consecutive ultra-short-term heart rate variability to track dynamic changes in autonomic nervous system during and after exercise.

Chen X ，Yao R ，Yin G ，Li J ... -  《-》

Linear and non-linear parameters of heart rate variability during static and dynamic exercise in a high-performance dinghy sailor.

Princi T ，Accardo A ，Peterec D 《-》