Computational modeling of left ventricular flow using PC-CMR-derived four-dimensional wall motion

Area of Science:

• Cardiovascular Imaging and Mechanics
• Computational Fluid Dynamics
• Biomedical Engineering

Background:

• Intracardiac hemodynamics is vital in cardiac and valvular diseases.
• Left ventricle (LV) blood flow simulations aid in understanding hemodynamics.
• Fully coupled fluid-solid LV modeling is complex due to myocardial wall behavior.

Purpose of the Study:

• To develop individualized LV models using integrated imaging and CFD for patient-specific hemodynamics.
• To characterize intracardiac LV hemodynamics using a novel moving-boundary CFD method.
• To leverage standard cardiac MRI protocols for feasible patient assessment.

Main Methods:

• Integrated two MRI modalities (cine CMR and PC-MRI) with a moving-boundary CFD method.
• Used non-rigid image registration (NRIR) on cine CMR for 4D endocardial motion, bypassing complex myocardial modeling.
• Applied PC-MRI data for time-resolved mitral inflow velocity in CFD simulations.

Main Results:

• Computed CFD flow patterns (streamlines, vortex rings, kinetic energy) and compared them with clinical data.
• Established relationships between LV wall kinematics and flow characteristics using the NRIR framework.
• Validated simulation fidelity by comparing aortic outflow tract flow rate with PC-MRI measurements.

Conclusions:

• The proposed methodology offers a novel and feasible approach for patient-specific LV hemodynamics.
• Leverages standard PC-CMR protocols for improved clinical assessment.
• Enhances prognostic studies and surgical planning for cardiac conditions.