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Updated: Jan 22, 2026

Slicing and Culturing Pig Hearts under Physiological Conditions
Published on: March 20, 2020
Generalized Poincaré plots analysis of heart period dynamics in different physiological conditions: Trained vs.
Mirjana M Platiša1, Tijana Bojić2, Sanja Mazić3
1Institute of Biophysics, Faculty of Medicine, University of Belgrade, Belgrade, Serbia.
Background:
Recently we proposed a new method called generalized Poincaré plot (gPp) analysis which gave a new insight into the pattern of neurocaridac control. In this study we examined potential of gPp method to reveal changes in cardiac neural control in young athletes during three conditions: supine rest, running and relaxation, with respect to untrained subjects.
Methods:
This method is based on the quantification of Pearson's correlation coefficients r(j, k), between symmetrical (j = k) and asymmetrical summed j previous and k following RR intervals up to the 100th order (j,k≤100).
Results:
Differences between groups were obtained at all levels of this analysis. The main result is the significant difference of NAI, normalized index of asymmetry, between groups in running, which was originated in different positions of local maxima of r(j, k). Compared with untrained subjects, these findings indicate modified neural control and altered intrinsic heart rate behavior in athletes which are related to some kind of memory mechanism between RR intervals.
Conclusion:
Obtained results provide great potential of gPp method analysis in the recognition of changes in neurocardiac control in healthy subjects. Further studies are needed for identification of altered cardiac regulatory mechanisms whose background may be useful in the evaluation of genesis of athletes neurocardiovascular pathology.
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