PURPOSE To create and characterize a physical Windkessel module that can provide realistic and predictable vascular impedances for in-vitro flow experiments used for computational fluid dynamics validation, and other investigations of the cardiovascular system and medical devices. METHODS We developed practical design and manufacturing methods for constructing flow resistance and capacitance ...

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...

The present study assessed (1) the impact of the measurement site (lower versus upper extremity) on the corresponding compliance variables and (2) the overall reliability of diastolic pulse contour (Windkessel-derived) analysis in normal and hypertensive subjects. Arterial tonograms were recorded in the supine position from the radial and posterior tibial arteries in 20 normotensive (116+/-12/6...

This paper presents a model-based approach to estimation of cardiac output (CO) and total peripheral resistance (TPR). In the proposed approach, the response of cardiovascular system (CVS), described by the windkessel model, is tuned to the measurements of systolic, diastolic and mean arterial blood pressures (BP) so as to yield optimal individual- and time-specific system time constant that is...

Two competing schools of thought ascribe vascular disease states such as isolated systolic hypertension to fundamentally different arterial system properties. The "windkessel school" describes the arterial system as a compliant chamber that distends and stores blood and relates pulse pressure to total peripheral resistance (R(tot)) and total arterial compliance (C(tot)). Inherent in this descri...

In the modeling of the pulse wave in the systemic arterial tree, it is necessary to truncate small arterial crowns representing the networks of small arteries and arterioles. Appropriate boundary conditions at the truncation points are required to represent wave reflection effects of the truncated arterial crowns. In this work, we provide a systematic method to extract parameters of the three-e...

The most common descriptor of afterload in the clinical setting is peripheral vascular resistance. Nonetheless, this is only one of the elements of afterload. A comprehensive descriptor of left ventricular extrinsic afterload is contained in the 3-element Windkessel (wind-chamber) model. Although this Windkessel circulatory model contains only characteristic impedance, aortic compliance and per...

Background: With increasing age, some changes appeared in specifications of vessels which including dimensions and elasticity in their. The changes in parameters such as resistance, inertance and compliance vessels appear and eventually changes in the environmental pulse releases are in circulation. These changes clearly appear in specification of photoplethysmogram particularly in the size and...

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...

Several works have separated the pressure waveform p in systemic arteries into reservoir p(r) and excess p(exc) components, p = p(r) + p(exc), to improve pulse wave analysis, using windkessel models to calculate the reservoir pressure. However, the mechanics underlying this separation and the physical meaning of p(r) and p(exc) have not yet been established. They are studied here using the time...