A simplified model of arterial blood pressure intended for use in model-based signal processing applications is presented. The main idea is to decompose the pressure into two components: a travelling wave which describes the fast propagation phenomena predominating during the systolic phase and a windkessel flow that represents the slow phenomena during the diastolic phase. Instead of decomposi...

Windkessel and similar lumped models are often used to represent blood flow and pressure in systemic arteries. The windkessel model was originally developed by Stephen Hales (1733) and Otto Frank (1899) who used it to describe blood flow in the heart. In this paper we start with the onedimensional axisymmetric Navier-Stokes equations for time-dependent blood flow in a rigid vessel to derive lum...

A simplified model of arterial blood pressure intended for use in model-based signal processing applications is presented. The main idea is to decompose the pressure into two components: a travelling wave describes the fast propagation phenomena predominating during the systolic phase and a windkessel flow represents the slow phenomena during the diastolic phase. Instead of decomposing the bloo...

This paper describes system analyze of the Windkessel models. The equations, space state and transfer functions of 2, 3 and 4 elements Windkessel models are described. The Simulink environment model schemas are presented as well. The Bode frequency and step response analyses are presented for all three models as well. Moreover the simulation of the special input signal which represents blood fl...

Within the last decade the quantification of pulse wave reflections mainly focused on measures of central aortic systolic pressure and its augmentation through reflections based on pulse wave analysis (PWA). A complementary approach is the wave separation analysis (WSA), which quantifies the total amount of arterial wave reflection considering both aortic pulse and flow waves. The aim of this w...

Arterial windkessel mechanisms and arterial pressure (AP) low frequency (LF) waves were investigated by means of simple lumped models of a compliant resistant/arterial tree and of flow regulation in peripheral vascular districts (PVDs) with three types of feedback: 1) delay, 2) Van der Pol oscillator, 3) relay; all were able to actively compensate flow changes and to simulate peripheral LF vaso...

Proper interpretation of BOLD fMRI and other common functional imaging methods requires an understanding of neurovascular coupling. We used laser speckle-contrast optical imaging to measure blood-flow responses in rat somatosensory cortex elicited by brief (2 s) forepaw stimulation. Results show a large increase in local blood flow speed followed by an undershoot and possible late-time oscillat...

3 Modelling 5 3.1 Elements of fluid mechanics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 3.2 Flow in blood vessels . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 3.3 Flow on a vessel graph . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 3.4 One-dimensional analysis . . . . . . . . . . . . . . . . ....

Some have said that it is inappropriate and perhaps impossible to consider wave Windkessel phenomena simultaneously. For 50 years, arterial hemodynamics has been dominated by the frequency-domain “impedance analysis” in which was assumed all variations aortic pressure flow were caused only forward- backward-going waves. This paper a review of results incorporating effects Frank’s Windkessel. We...

Objectives To test the usefulness of continuous assessment of arterial load based on a 3-element Windkessel model by a combined analysis of the esophageal Doppler derived-blood flow and arterial pressure waveform, against standard frequency-domain analysis of arterial impedance. Methods Time-domain variables of arterial impedance were obtained by the simultaneous analysis of the Doppler derived...