Modeling of restenosis of main arteries after the intravascular stenting interventions

Objectives to study the mechanism of restenosis after the intra-arterial stenting using the original device for modeling of intra-arterial blood flow. Material and methods. To perform the experiment, we have created the original device simulating the intra-arterial blood flow. A glass tube of rotameter was the imitation of the arterial vessel. The closed system was filled with the liquid imitating blood, specifically the solution of glycerin the same viscosity as the human blood plasma. Using our original model of intra-artetial blood flow, we were able to study the intra-arterial hemodynamics under different conditions of cardiovascular system functioning, including arrhythmias. Results. In extrasystolic arrhythmia, during the spread of the first post-extrasystolic wave, we observed the intensive impact of pressure wave (the indicator was the silk thread) on the vessel walls with forming of reflected and standing waves. Putting the piezo crystal probe of pressure inside the tube, we verified our observations. The increase of pressure during the spread of the first post-extrasystolic wave in multiple measurements had a mean value of 160% in comparison with the pressure during the regular heart rhythm. Conclusion. The hydraulic shock appears during the spread of the first post-extrasystolic wave in the arterial vessel. Its effect on hemodynamics grows in case of the frequent extrasystoles and allorhythmia. The mechanical impact of hydraulic shock in extrasystoles can be the starting point of the restenosis onset and progressing in the intra-arterial stent.

Download Full-text

Upper Extremity Vein Graft Monitoring Device after Surgery Procedure: A Preliminary Study

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.925.656 ◽

2014 ◽

Vol 925 ◽

pp. 656-660 ◽

Cited By ~ 3

Author(s):

Hoi Leong Lee ◽

Abu Bakar Shahriman ◽

Siti Khadijah Za'aba ◽

Khairunizam Wan ◽

S. Ahmad Roohi ◽

...

Keyword(s):

Blood Flow ◽

Blood Volume ◽

Vein Graft ◽

Graft Failure ◽

Low Cost ◽

High Rate ◽

Arterial Blood Flow ◽

Arterial Blood ◽

Starting Point ◽

Vein Graft Failure

In most cases, surgical vein bypass or interposition vein grafting was used in both primary management of crush-avulsion amputations and on intervention for rehabilitating the patency of occluded arteries via microvascular surgery. However, surgical revascularization has significant shortcomings, principal among which is the high rate of accelerated thrombosis that develops in arterialised vein graft which renders the vein graft susceptible to acute occlusion and eventually give rise to graft failure. Evaluaion and detection of vein graft failure is essential as that will be the starting point for the clinician to make the diagnosis and safeguard patency of implanted vein graft which would otherwise fail. Unfortunately, most of the available diagnostic and monitoring tools available in the market are expensive, hence not all the hospital, private clinic and others medical centers that fully-equipped with these type of equipments. The objective of this study is to design and develop a low-cost and non-invasive vein graft monitoring prototype that able to provide high accuracy in predicting the vein graft patency and meanwhile providing the short-term monitoring on vein graft right after surgery procedure. Impedance plethysmography (IPG) was employed to measure pulsatile changes in longitudinal impedace to quantify arterial blood flow and pulsatile blood volume. Tetra-polar electrode measurement system was implemented by introduce a constant 1-mA AC current (I) at frequency of 100 kHz in the two outer electrodes. The voltage (V) is measured between the two inner electrodes, and the resulting impedance (Z) is calculated using Ohm’s Law. Arterial blood flow and pulsatile blood volume can then be estimated using impedance related volume conduction equation. By measuring the changes in electrical bioimpedance which can be used to derive important hemodynamic variables, it allows the postoperative graft surveillance and early detection atherosclerosis and thrombosis as well as estimate its severity that leads to the vein graft failure.

Download Full-text

Changes in Umbilical Arterial Blood Flow by an Intraamniotic Distilled Water Infusion

Yearbook of Obstetrics Gynecology and Women s Health ◽

10.1016/s1090-798x(08)70024-9 ◽

2007 ◽

Vol 2007 ◽

pp. 30-31

Author(s):

S.H. Ural

Keyword(s):

Blood Flow ◽

Arterial Blood Flow ◽

Distilled Water ◽

Arterial Blood ◽

Water Infusion

Download Full-text

Impact of Pre Transplant Transarterial Chemoembolization on Hepatic Arterial Blood Flow and Outcomes in Liver Transplantation

10.26226/morressier.58eb975dd462b80290b50084 ◽

2017 ◽

Author(s):

Siddharth Jain

Keyword(s):

Liver Transplantation ◽

Blood Flow ◽

Transarterial Chemoembolization ◽

Arterial Blood Flow ◽

Hepatic Arterial Blood Flow ◽

Arterial Blood

Download Full-text

Modeling Elastic Walls in Lattice Boltzmann Simulations of Arterial Blood Flow

SNE Simulation Notes Europe ◽

10.11128/sne.23.tn.10189 ◽

2013 ◽

Vol 23 (2) ◽

Author(s):

Xenia Descovich ◽

Giuseppe Pontrelli ◽

Sauro Succi ◽

Simone Melchionna ◽

Manfred Bammer

Keyword(s):

Blood Flow ◽

Lattice Boltzmann ◽

Arterial Blood Flow ◽

Arterial Blood ◽

Lattice Boltzmann Simulations ◽

Elastic Walls

Download Full-text

Sustained Inflation Reduces Pulmonary Blood Flow during Resuscitation with an Intact Cord

Children ◽

10.3390/children8050353 ◽

2021 ◽

Vol 8 (5) ◽

pp. 353

Author(s):

Jayasree Nair ◽

Lauren Davidson ◽

Sylvia Gugino ◽

Carmon Koenigsknecht ◽

Justin Helman ◽

...

Keyword(s):

Blood Flow ◽

Perinatal Asphyxia ◽

Arterial Blood Flow ◽

Positive Pressure ◽

Optimal Timing ◽

Delayed Cord Clamping ◽

Arterial Blood ◽

Cord Clamping ◽

Sustained Inflation ◽

Near Term

The optimal timing of cord clamping in asphyxia is not known. Our aims were to determine the effect of ventilation (sustained inflation–SI vs. positive pressure ventilation–V) with early (ECC) or delayed cord clamping (DCC) in asphyxiated near-term lambs. We hypothesized that SI with DCC improves gas exchange and hemodynamics in near-term lambs with asphyxial bradycardia. A total of 28 lambs were asphyxiated to a mean blood pressure of 22 mmHg. Lambs were randomized based on the timing of cord clamping (ECC—immediate, DCC—60 s) and mode of initial ventilation into five groups: ECC + V, ECC + SI, DCC, DCC + V and DCC + SI. The magnitude of placental transfusion was assessed using biotinylated RBC. Though an asphyxial bradycardia model, 2–3 lambs in each group were arrested. There was no difference in primary outcomes, the time to reach baseline carotid blood flow (CBF), HR ≥ 100 bpm or MBP ≥ 40 mmHg. SI reduced pulmonary (PBF) and umbilical venous (UV) blood flow without affecting CBF or umbilical arterial blood flow. A significant reduction in PBF with SI persisted for a few minutes after birth. In our model of perinatal asphyxia, an initial SI breath increased airway pressure, and reduced PBF and UV return with an intact cord. Further clinical studies evaluating the timing of cord clamping and ventilation strategy in asphyxiated infants are warranted.

Download Full-text