# cardiovascular system

## 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.

## 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.