Izvestiya of Saratov University.
ISSN 1817-3020 (Print)
ISSN 2542-193X (Online)

cardiovascular system

Decrease of low-frequency spectral power in a heart rate variability signal in a mathematical model of the cardiovascular system of arterial hypertension patients

Background and Objectives: Index equal to the spectral power of the low-frequency oscillations from the time series of the time intervals between the hearts contractions are often used when investigating the cardiovascular system. Experimental studies have shown that this spectral index was a preclinical marker of cardiovascular diseases, including arterial hypertension and diabetes.

Development of a digital finger photoplethysmogram sensor

Background and Objectives: Due to the development of methods for analyzing signals of autonomous blood circulation control, cardiovascular system disorders can be diagnosed today in the early stages. It is promising to use specialized devices for personalized diagnosis of the cardiovascular system and monitoring its state. Research on autonomous blood circulation control systems is a complex problem both from the point of view of physiology and radiophysics.

Model of Cardiovascular System Autonomic Regulation with a Circuit of Baroreflectory Control of Mean Arterial Pressure in the Form of Delayed-Feedback Oscillator

A mathematical model of human cardiovascular system autonomic regulation is proposed having the form of differential equation set. Some equations of the model contain terms with time delay. The spectral analysis shows that the proposed model exhibits better qualitative and quantitative coincidence with experimental data than the known models.

Investigation of Delay Time in Interaction between the Regulatory Circuits in the Cardiovascular System of Healthy Humans Using Modeling of Phase Dynamics

Background and Objectives: Low-frequency oscillations with a basic frequency of about 0.1 Hz are observed in the human heart rate and peripheral microcirculation. It is found out that these processes are self-oscillatory and interact between themselves. However, the details and characteristics of this interaction including the direction of coupling and delays in coupling functions are not well studied yet.