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Updated: Jun 27, 2026

Software for Analysis of Heart Rate and Blood Pressure Time-series Data from the Valsalva Maneuver
Published on: June 27, 2025
The effect of orthostasis on recurrence quantification analysis of heart rate and blood pressure dynamics
M Javorka1, Z Turianikova, I Tonhajzerova
1Institute of Physiology, Jessenius Faculty of Medicine, Comenius University, Mala Hora 4, Martin, Slovak Republic. mjavorka@lefa.sk
Abstract:
The purpose of this paper is to investigate the effect of orthostatic challenge on recurrence plot based complexity measures of heart rate and blood pressure variability (HRV and BPV). HRV and BPV complexities were assessed in 28 healthy subjects over 15 min in the supine and standing positions. The complexity of HRV and BPV was assessed based on recurrence quantification analysis. HRV complexity was reduced along with the HRV magnitude after changing from the supine to the standing position. In contrast, the BPV magnitude increased and BPV complexity decreased upon standing. Recurrence quantification analysis (RQA) of HRV and BPV is sensitive to orthostatic challenge and might therefore be suited to assess changes in autonomic neural outflow to the cardiovascular system.
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