Computational Analysis of Flow Structures in Turbulent Ventricular Blood Flow Associated With Mitral Valve...

Area of Science:

• Cardiovascular dynamics
• Biomedical engineering
• Computational fluid dynamics

Background:

• Cardiac disease and interventions can alter blood flow, increasing thrombosis risk.
• Mechanical forces on blood cells, particularly platelets, influence activation.
• Understanding intraventricular flow mechanics is key to mitigating thrombotic events.

Purpose of the Study:

• To analyze blood flow in the left ventricle using patient-specific data.
• To investigate the impact of mitral valve interventions on intraventricular flow dynamics.
• To differentiate flow structures and their mechanical stimuli on blood cells.

Main Methods:

• Developed a computational model of left ventricular blood flow using Navier-Stokes equations.
• Employed a parameterized model for mitral valve flow and a finite element method for solving equations.
• Utilized triple decomposition of the velocity gradient tensor to analyze flow structures (rotation, strain, shear).

Main Results:

• Mitral valve clip intervention significantly modified intraventricular flow patterns.
• Shear stress increased more in clipped cases compared to untreated cases.
• Reduced valve opening area led to substantial increases in rotation, strain, and particularly shear.

Conclusions:

• Computational analysis provides insights into shear-induced platelet activation.
• The study offers an algorithm to distinguish shear from other flow modalities in the left ventricle.
• Findings can improve models of platelet activation in cardiac conditions and interventions.