Foundation of Cardiac Surgery Development

Simulation of aorta model with bicuspid aortic valve (BAV). The dilated part of the ascending aorta was replaced with a vascular prosthesis. Lines of flow were obtained from computer simulation of a 65-year-old male patient with a dilated aorta and BAV. Image also shows distribution of aortic wall shear stresses.

Problem:

Bicuspid aortic valve is the most common congenital cardiac malformation in adults. BAV is strongly associated with vascular complications such as aortic root dilatation, thoracic aortic aneurysm and aortic dissection. Accurately estimating changes in basic hemodynamic parameters and reducing the risk of aortopathy and valve dysfunction can improve long-term BAV patient outcomes. Computer modeling based on patient-specific CT images can define parameters, which in clinical conditions are very difficult or sometimes impossible to measure. The opening and closing of the aortic valve is the result of complex interactions between valve leaflets, the aortic root and blood. Therefore, to study the events that take place as the blood flows through the aortic valve, computer-based fluid-structure interaction simulation was used with a flexible aortic wall and flexible aortic valve leaflets.

Solution:

ANSYS Multiphysics software was used to determine the flow pattern, turbulence, stagnation area, shear stress, wall deformation and turbulence eddy dissipation based on a numerical solution of the Navier-Stokes and continuity equations. FSI evaluated the degree to which geometric changes of a dilated aorta influence the flow distribution and basic hemodynamic parameters in patients with BAV.

Software used:

  • ANSYS Multiphysics