دانلود رایگان مقاله بررسی همودینامیک تاثیر ترومبوز داخل مجرا بر فشار دیوار تحت جریان ضربانی

Abstract

Purpose: Aortic aneurysms occurs when the wall stress exceeds the strength of the vascular tissue. Intraluminal Thrombus (ILT) may absorb tension and reduce the aortic aneurysm wall stress. The purpose of this study is to test the hypothesis that the presence and growth of ILT alters the wall stress in a stented aneurysm. Method: A virtual stented aneurysm model with ILT is created to study the flow and wall dynamics by means of Fluid-Structure Interaction (FSI) analysis. Wall stresses are determined by two-dimensional axisymmetric finite element analysis. Calculations are performed as thrombus elastic modulus increased from 0.1 to 2 MPa and calculations are repeated as thrombus depth is increased in 10% increment until thrombus fills the entire aneurysm cavity. Results: The blood flow velocity, pressure, and maximum wall stresses are compared to the aforementioned models. The maximum stress reduction of 46% occurs at the time of peak flow and 28% at the time of peak pressure when thrombus elastic modulus increases from 0.1 to 2 MPa. In addition, as the thrombus depth increased from 10% to 100 %, the wall stress at the time of peak flow and peak pressure decreased almost 25% and 20%. Conclusions: The findings of this study may have implications not only for understanding the wall stress in ILT but also for providing more detailed information about aortic aneurysm with intraluminal thrombus.

Conclusion

The purpose of present study was to investigate hemodynamic parameters like blood flow velocity, pressure and wall stress distribution through a stented aortic aneurysm with intraluminal thrombus. A two-dimensional axisymmetric model of aortic aneurysm with various both depth and elastic modulus of thrombus in the presence of pulsatile flow with considering fluid-solid interaction was simulated. The results revealed that the wall stress decreases by the growth of thrombus elastic modulus for both times of peak flow and peak pressure and the difference between pressure values of the inlet and outlet at the time of peak pressure decreases in the case of reduction in difference between elastic modulus of intima and thrombus.