Recurrence quantification analysis describes the complex and deterministic behavior of heart rate variability in healthy subjects

This study highlights the application of recurrence quantification analysis (RQA) to derive information about nonlinear properties of heart rate variability (HRV). Parameters introduced by RQA, based on distance, recurrence and entropy of Recurrence Plots (RPs), show a natural application to cardiovascular signals, as descriptors of variable inherent complexity and determinism in different physiological conditions. RQA was applied to RR interval series collected in healthy subjects during relaxation, providing quantitative markers associated with the presence of complexity and determinism in HRV.