Effects of aortic irregularities on blood flow

Area of Science:

• Cardiovascular fluid dynamics
• Biomedical engineering
• Computational biology

Background:

• Anatomic aortic anomalies disrupt blood flow.
• Turner syndrome (TS) frequently presents with cardiovascular anomalies, especially aortic issues.

Purpose of the Study:

• Investigate blood flow characteristics in four patient-specific Turner syndrome aortic arch geometries.
• Analyze the impact of aortic anomalies on flow structures and red blood cell (RBC) distribution.
• Evaluate the significance of non-Newtonian blood behavior.

Main Methods:

• Employed numerical simulations to model blood flow.
• Utilized the Quemada viscosity model for non-Newtonian blood properties.
• Represented blood as a mixture of water and convected scalar RBCs.

Main Results:

• Observed significant geometry-dependent differences in flow structures and RBC distribution.
• Identified transitional flow and jet formation in the coarctation case due to aortic constriction.
• Found varying RBC dilution across geometries, impacting wall shear stress (WSS).
• Demonstrated that local RBC volume fraction variations induce significant viscosity changes.

Conclusions:

• Aortic arch geometry critically influences hemodynamics and RBC distribution in Turner syndrome.
• Non-Newtonian blood properties are essential for accurate simulation of flow in anomalous aortas.
• Understanding these effects is crucial for managing cardiovascular risks in Turner syndrome.