Stimulus evoked changes in cerebral blood flow, volume, and oxygenation arise from responses to underlying neuronally mediated changes in vascular tone and cerebral oxygen metabolism. There is increasing evidence that the magnitude and temporal characteristics of these evoked hemodynamic changes are additionally influenced by the local properties of the vasculature including the levels of basel...

BACKGROUND Counter-pulsation control (CPC) by ventricular assist devices (VADs) is believed to reduce cardiac load and increase coronary perfusion. However, patients with VADs have a higher risk of arrhythmia, which may cause the CPC to fail. Consequently, CPC has not been applied by VADs in clinical practice. The phase-locked loop (PLL) algorithm for CPC is readily implemented in VADs; however...

Cardiovascular system modeling involves a great number of parameters (resistances, compliances, network geometries, etc.) which are unknown a priori and need to be identified. The present work aims at developing an identification procedure for estimating subject-specific hemodynamic parameters based on a one-dimensional (1-D) tree-like vascular flow model. For the present identification method,...

Wave separation analysis and wave intensity analysis (WIA) use (aortic) pressure and flow to separate them in their forward and backward (reflected) waves. While wave separation analysis uses measured pressure and flow, WIA uses their derivatives. Because differentiation emphasizes rapid changes, WIA suppresses slow (diastolic) fluctuations of the waves and renders diastole a seemingly wave-fre...

The new version of the hydro-electro-mechanical system (HEMS) is modeled via 14 serially connected electrical equivalent circuits resulting in an integrated circuit. model accepts a group variables and even examines interaction between them. This paper introduces improved heart by replacing monolithic structures with segmental comprehensive equivalents. Windkessel Model (WM) relationships aorta...

Abstract Pulmonary arterial hypertension (PAH) is a rare disorder characterized by elevated blood pressure and pulmonary vascular resistance, often followed right ventricular hypertrophy heart failure. The effect of PAH its treatments on the mechanics, function, remodelling ventricle (RV) currently not well understood. To study cardiac biomechanics functionality as progresses, we implemented co...