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Endovascular technologies and reconstructive interventions on profound femoral artery at revascularization of multilevel stenotic-occlusive process of infrainguinal arterial channel

100%

Herasymiuk N. I. , Husak M. O. , Venher I. K. , Kovalskyy D. V. , Loyko I. I. , Selskyy B. P.

Journal of Education, Health and Sport

2021

tom 11

nr 1

153-162

Introduction. Number of patients with obliterating lesions of the aorta and main arteries of the lower extermities has been steadily increasing every year. When choosing the scope of surgical treatment all the features of the multilevel stenotic-occlusive process of the infrainguinal arterial bed should be taken into account. Purpose. To improve the results of revascularization of the infrainguinal arterial bed by applying surgical intervention on profound femoral artery and endovascular methods to restore permeability of the outflow arteries. Materials and methods. The work is based on the results of examination and surgical treatment of 264 patients with stenotic-occlusive process of the infrainguinal arterial bed. There were four groups of patients. The basis of revascularization interventions on the infranguinal artery was shunt surgery. Bypass surgery was performed using a reverse autovein. The combined shunt was used for localization of the distal anastomosis at the level of the popliteal, shin arteries, tibioperinel trunk. Results. In atherosclerotic stenotic-occlusive lesions of the infrainguinal arterial bed of the lower extremity, the volume of surgical treatment depends on the level of the occlusive process, the functional state of the PFA and the blood flow pathways. And the method of surgical intervention in shunt interventions is determined by the type of distal lesion and the level of imposition of distal and proximal anastomoses. Conclusion. The use of endovascular methods of revascularization and reconstructive interventions on PFA in combination with femoral-distal shunt operations contributes to good and satisfactory results of surgical treatment of stenotic-occlusive processes of the infrainguinal arterial bed.

Prediction of vortex structures in pulsatile flow through S-bend arterial geometry with different stenosis levels

63%

Khan P. M. , Raj A. , Alam M. I. , Chakraborty S. , Roy S.

Biocybernetics and Biomedical Engineering

2023

tom Vol. 43, no. 1

298--312

Arterial stenosis poses a high cardiovascular risk, and clinical intervention is needed when these stenoses grow beyond a specific limit. The study of vortex dynamics in these diseased arteries can be beneficial to understand its severity. Therefore, in the present work, we have investigated the flow structures in an S-bend arterial geometry with different levels of stenosis using a sharp interface immersed boundary method. We have observed an onset of Kelvin-Helmholtz-type vortex roll-up for higher degrees of stenoses. Fluctuations in the wall shear stress are observed for higher stenosis degrees. However, these fluctuations depend on the position and length of the stenosis. Newtonian and non-Newtonian Carreau fluids predict similar vortex structures, although minor differences in the Kelvin-Helmholtz vortex structures and associated fluctuations are observed in the diastolic phase. The Newtonian fluid predicts a slightly longer low time-averaged wall shear stress (≤0.5 Pa) region immediately after the stenosis compared with the Carreau fluid in the 58 % blockage S-bend artery.

Mathematical analysis of mass and heat transfer through arterial stenosis

51%

Hussain A. , Sarwar L. , Akbar S. , Malik M. Y.

Journal of Power Technologies

2022

tom Vol. 102, nr 3

88--95

The article investigates the steady state flow of an incompressible fluid which is treated as a Williamson fluid through a stenoised region in the shape of cosine constriction. Blood is taken as a Williamson fluid. Mathematical formulation leads us to nonlinear compatibility and energy equations, which are then deciphered by the shooting technique to obtain the numerical solution. Suitable resemblance transformations are used to change partial differential equations into an embellished form of ordinary differential equations. Further, the consequences of the different parameters involved are shown by graphs and a conclusion is presented. Velocity and temperature fields are canvassed graphically for the distinct values of emerging parameters and discussed in tabular form. Skin friction and the coefficient of heat transfer are also covered in the discussion. The resulting Nusselt number curve exhibits negative deflection for variational values of λ and height of the stenosis δ.