Jung et al.34 (2007) randomly allocated 13 Yorkshire pigs to two groups for pulsatile (twin pulse pump, n=7) versus non-pulsatile (biopump, n=6) VAD treatment after electrically induced ventricular fibrillation and investigated the flow in the left coronary artery. After 20, 40, 60, 80, 100 and 120 min, they measured mean coronary flows of 0.77±0.3, 0.76±0.19, 0.95±0.23, 0.86±0.23, 1.00±0.24 an...

In the abdominal segment of the human aorta under a patient's average resting conditions, pulsatile blood flow exhibits complex laminar patterns with secondary flows induced by adjacent branches and irregular vessel geometries. The flow dynamics becomes more complex when there is a pathological condition that causes changes in the normal structural composition of the vessel wall, for example, i...

Pulsatile Flow Analysis of the Femoral Artery To the Editor: We read with great interest the article, “Pulse Pressure Amplification, Arterial Stiffness, and Peripheral Wave Reflection Determine Pulsatile Flow Waveform of the Femoral Artery” by Hashimoto et al,1 studying the correlation between reverse diastolic blood flow and increased arterial stiffness in the femoral artery. The authors empha...

____________ _ (}. Extra-Corpor. Techno/. 20[ 1]: p. 24-29, 60 references, Spring 1988) Pulsatile perfusion has been a topic of great controversy for many years. This paper reviews historical aspects of pulsatile perfusion, as well as current and conceptual aspects of pulsatile perfusion. The positive and negative points of pulsatile perfusion are discussed so the reader may draw conclusions in...

Transition of additive and non-additive pulsatile flows through a simple 3D model of arterial stenosis is investigated by using a large eddy simulation (LES) technique. We find in both the pulsatile cases that the interaction of the two shear layers, one of which separates from the nose of the stenosis and the another one from its opposite wall, causes recirculation in the flow downstream of th...

The cardiovascular disease is one of most frequent cause deaths in modern society. The objective of this work is analyse the effect of dynamic vascular geometry (curvature, torsion, bifurcation) and pulsatile blood nature on secondary flow, wall shear stress and platelet deposition. The problem was examined as multi-scale physical phenomena using perturbation analysis and numerical modelling. T...

OBJECTIVE To investigate the effect of pulsatility of venous flow waveform in the inferior and superior caval vessels on the performance of functional and "failing" Fontan patients based on two primary performance measures - the conduit power loss and the distribution of inferior caval flow (hepatic factors) to the lungs. METHODS Doppler angiography flows were acquired from two typical extra-...

Endothelial cytosolic pH (pH(i)) modulates ion channel function, vascular tone, and cell proliferation. Steady shear induces rapid acidification in bicarbonate buffer. However, in vivo shear is typically pulsatile, potentially altering this response. We tested effects and mechanisms of pH(i) modulation by flow pulsatility, comparing pressurized steady versus pulse-flow responses in bovine aorti...

BACKGROUND Patients with advanced heart failure have improved survival rates and quality of life when treated with implanted pulsatile-flow left ventricular assist devices as compared with medical therapy. New continuous-flow devices are smaller and may be more durable than the pulsatile-flow devices. METHODS In this randomized trial, we enrolled patients with advanced heart failure who were ...

OBJECTIVE With a high-frequency percussive ventilator and a mechanical lung model, to measure tidal volume (V(T)), pulsatile pressure amplitude (difference between peak and nadir pulsatile pressure [DeltaP];), and mean airway pressure (P (aw)) at various pulsatile frequencies, pulsatile inspiratory-expiratory ratios (I:E(p)), and pressures (measured at the interface between the pulse-generator ...