Hemodynamic Numerical Simulation Of Before And After Carotid Artery Stenting On Carotid Artery Stenosis

Objective: To evaluate the hemodynamic characteristics of before and aftercarotid artery stenting(CAS) on carotid artery stenosis with the special two-dimensionalcervical carotid artery blood flow mechanics model by computer fluid dynamicsnumerical simulation base on patients’ digital subtraction angiography images.Methods: Cervical carotid artery blood flow mechanics models before and aftercarotid artery stenting were conducted in ten patients with carotid artery stenosis. Thecontour of carotid artery stenosis were intercepted by Photoshop software.The2-dimensional coordinates of the contour were showed by Matlab software.Gambitsoftware formed the stenosis shape, meshed two-dimensional grid and set boundaryconditions.Fluent software was used to simulate the blood flow. Comparedhemodynamic parameters of wall shear stress, pressure and blood flow velocity betweenbefore and after CAS.Results: Numerical simulation calculation indicated that compared with thosebefore operation,there were significant changes in hemodynamic parameters afteroperation. The mean preoperative blood flow velocity at position of stenosis was7.83±5.00m/s, postoperative was2.18±0.66m/s, P <0.05.The mean preoperative bloodflow velocity at post-stenosis part was0.72±0.35m/s, postoperative was1.91±0.22m/s, P <0.05.Average preoperative pressure at position of stenosis was9008±2211.01Pa,postoperative was13460±1655.43Pa, P <0.05. The mean preoperative pressure atpost-stenosis part was3562±1536.18Pa, postoperative was11677±2524.57Pa, P <0.05.The mean preoperative WSS at position of stenosis was3.57±2.68Pa, postoperativewas0.95±0.36Pa, P <0.05.Conclusion: Special2-dimensional hemodynamic numerical simulation isfeasible when the rate of cervical carotid artery stenosis is more than95%.Thenumerical simulation is a good method for evaluating hemodynamic characteristicsbefore and after CAS. Comparing with pre-CAS，the blood flow velocity at the positionof stenosis decrease, the blood flow velocity at the position of post-stenosis partincrease, the pressure at the position of stenosis increase, the pressure at the position ofstenosis post-stenosis part increase and the WSS at the position of stenosis decreaseafter CAS.