The goal of this study was to review the origin, clinical relevance and treatment of pulse pressure (PP). Elevated PP is increasingly being recognized as a risk factor for cardiovascular, particularly coronary, disease. Pulse pressure is discussed in terms of both Windkessel and distributive models of the arterial circulation. Pulse pressure arises from the interaction of cardiac ejection (stro...

Introduction. Recent studies report reduced vascular compliance and elevated levels of fibroblast growth factor 23 (FGF23) in patients with autosomal dominant polycystic kidney disease (ADPKD) and preserved kidney function. In the present study, we investigated the relationship between vascular compliance and FGF23 in patients in early phases of ADPKD. Materials and Methods. We studied 54 ADPKD...

The purpose of this study is to validate numerical simulations of flow and pressure in an abdominal aortic aneurysm (AAA) using phase-contrast magnetic resonance imaging (PCMRI) and an in vitro phantom under physiological flow and pressure conditions. We constructed a two-outlet physical flow phantom based on patient imaging data of an AAA and developed a physical Windkessel model to use as out...

The effects of acute changes in circulating blood volume on embryonic vascular hemodynamics were evaluated with the use of input impedance. We simultaneously measured dorsal aortic pressure with a servo-null system and flow velocity with a 20-MHz pulsed Doppler system in n = 90 stage 24 chick embryos. We withdrew or infused 1,3, or 5 microliters of blood via a second-order vitelline vein (n = 1...

Recent clinical and animal studies have suggested that ventricular-vascular coupling normally operates at either optimal ventricular efficiency (EFF = stroke work/myocardial oxygen consumption) or stroke work (SW) and that efficiency in particular is compromised by cardiac dysfunction. These distinctions between coupling states at maximal work vs. efficiency are largely based on theoretical mod...

We have measured the changes in oxy-haemoglobin and deoxy-haemoglobin in the adult human brain during a brief finger tapping exercise using near-infrared spectroscopy (NIRS). The cerebral metabolic rate of oxygen (CMRO2) can be estimated from these NIRS data provided certain model assumptions. The change in CMRO2 is related to changes in the total haemoglobin concentration, deoxy-haemoglobin co...

BACKGROUND Atherosclerosis begins in the arterial wall, with endothelial dysfunction accompanied by functional and structural changes that influence arterial stiffness. Pulse contour analysis provides an assessment of compliance or elasticity of the large conduit arteries (C(1)) and small microcirculatory arteries (C(2)). In this study, the predictive value of reduced elasticity of these arteri...

This study combines experimental and modeling approaches in order to investigate the temporal dynamics of the human brain at rest. The dynamics of the neuronal activity is modeled with FitzHugh-Nagumo oscillators and the blood-oxygen-level-dependent (BOLD) time series is inferred via the Balloon-Windkessel hemodynamic model. The simulations are based on structural connections that are derived f...