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bioRxiv · 10.1101/2023.03.23.534047

Model based concept to extract heart beat-to-beat variations beyond respiratory arrhythmia and baroreflex

Baranauskas, M.·Stanikunas, R.·Kaniusas, E.·Lukosevicius, A.
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Abstract

Heart rate (HR) and its variability (HRV) reflect the autonomous nervous system (ANS) modulation, especially sympathovagal balance. This work aims to present concept of a personalizable HR model and an in silico system to identify the HR regulation parameters and subsequently capture residual heart beat-to-beat variations from individual psychophysiological recordings in humans. The model encompasses respiratory sinus arrhythmia (RSA) and baroreflex mechanisms, and uses respiration and blood pressure signals and the time instances of R peaks from an electrocardiogram as inputs. The system extracts the residual displacements of the modeled R peaks relative to the real R peaks. Three components - tonic, spontaneous, and 0.1 Hz changes - can be derived from these R peak residual displacements and can, therefore, enhance HRV analysis beyond RSA and baroreflex. Our model-based concept suggests that these residuals are not merely modeling errors. The proposed method could help to investigate additional neural regulation impulses from the higher-order brain and other influences.

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Baranauskas, M., Stanikunas, R., Kaniusas, E., Lukosevicius, A.. 2023-03-25. Model based concept to extract heart beat-to-beat variations beyond respiratory arrhythmia and baroreflex. https://doi.org/10.1101/2023.03.23.534047

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