Evaluation of the time delay in connection between low-frequency circuits of autonomic regulation of blood circulation in patients with arterial hypertension

The aim of this study was to study the features of interaction between low-frequency (LF) contours of vegetative regulation of blood circulation in patients with arterial hypertension (AH) and in healthy individuals. Material and Methods — This study included 127 synchronous records of cardiointervalograms and photoplethysmograms from patients with AH (aged 39-55 years) and 40 records from healthy subjects (aged 20-40 years). Synchronization of the LF rhythms was estimated by calculating the total percentage of phase synchronization, the phase increment correlation, the prediction error, and the phase coherence index. Results — It is revealed that the average values of time delays in communication between studied contours are somewhat lower in healthy people than in patients with AH. At the same time, the strength of this interaction is approximately similar in both studied groups. Conclusion — Patients with AH are characterized by a greater delay in the relationship between LF rhythms in regulation of heart rate and peripheral blood flow, relatively healthy individuals.