Numerical Simulation of Hemodynamics of Left Ventricular Assist Device for Surgical Planning translation missing: zh.hyrax.visibility.files_restricted.text

Sun, Hanyao (Spring 2019)

Permanent URL: https://etd.library.emory.edu/concern/etds/vd66w084n?locale=zh
Published

Abstract

Left ventricular assist devices (LVAD), which facilitate blood flow from the left ventricle to the aorta, are a surgical option for patients with end-stage congestive heart failure, a condition that the heart fails to pump enough blood to meet the body’s need. LVAD can be surgically implanted through a left thoracotomy with outflow-graft anastomosis. Generally, the approach of LVAD should be considered when the left ventricle fails to provide more than 70% of blood flow. In this research, we investigated on three LVAD configuration positions: axial-flow and transversal-flow LVAD on ascending aorta and axial-flow LVAD on descending aorta. The position at which the graft is configured may have important clinical consequences depending on various severity of heart failure. We describe a computer-generated model to illustrate the flow dynamics in the aorta with respect to different outflow-graft configurations under various degrees of heart failure. 

The simulation indicates that the location of the anastomosis has important effect on blood flow in the ascending aorta, the aortic arch and the descending aorta. Moreover, under the condition of 50% blockage of aortic root, LVAD is not generally recommended because the hazard associated with open heart surgery could outweigh its overall benefit. However, our simulation suggests that if LVAD is implanted under such condition, its configuration position does not make a significant impact to hemodynamics inside the aorta comparing to that of premorbid aorta. Under the condition of 70% blockage of aortic root, this is when LVAD implantation should be generally considered. The simulation indicates that under this scenario, axial-flow LVAD on descending aorta is the most optimal solution. The most extreme case of heart failure is 100% blockage of aortic root, meaning that the only source of blood supply is through LVAD. The simulation indicates that under this extreme case, transversal-flow LVAD on ascending aorta could be the most promising option. Results of this study provide insight on the importance of the anastomosis location on the hemodynamics in the aorta, systolic pressure on the aortic wall, velocity and vorticity of blood flow inside the aorta. 

Table of Contents

Table of Contents

Introduction 1

Geometrical Modeling 5

Physical Modeling (Navier-Stokes Fluid Dynamics) 8

Code 15

Computer Simulation Results 19

Discussion 34

Reference 39

About this Honors Thesis

Rights statement
  • Permission granted by the author to include this thesis or dissertation in this repository. All rights reserved by the author. Please contact the author for information regarding the reproduction and use of this thesis or dissertation.
School
Department
Degree
Submission
Language
  • English
Research field
关键词
Committee Chair / Thesis Advisor
Committee Members
最新修改

Primary PDF

Supplemental Files