Cardiac flow analysis applied to phase contrast magnetic resonance imaging of the heart

Area of Science:

• Cardiovascular Imaging
• Biomedical Engineering
• Fluid Dynamics

Background:

• Accurate assessment of blood flow dynamics within the heart is crucial for understanding cardiac function and diagnosing abnormalities.
• Traditional methods may not fully capture the complex, three-dimensional nature of intracardiac blood flow patterns.
• Phase contrast magnetic resonance imaging (PC-MRI) offers a non-invasive approach to visualize and quantify blood flow.

Purpose of the Study:

• To demonstrate and quantify changes in swirling blood flow within cardiac chambers using PC-MRI.
• To characterize the location and strength of large-scale vortices in the heart.
• To establish reference data for clinical analysis of cardiac flow patterns and abnormalities.

Main Methods:

• Phase contrast magnetic resonance imaging (PC-MRI) was employed to generate blood flow fields.
• Velocity fields were acquired by projecting 3D blood flow onto multiple planes.
• Streamlines and vector plots were utilized to illustrate blood dynamical behavior across cardiac phases.
• Temporal vorticity fields were analyzed to track changes in blood swirls over a cardiac cycle.

Main Results:

• Large-scale vortices were observed within the heart chambers.
• A technique was developed to characterize the location and strength of these vortices.
• Changes in blood swirls over a cardiac cycle were successfully indicated using temporal vorticity fields.
• Detailed blood flow patterns and dynamical behavior were illustrated using streamlines and vector plots.

Conclusions:

• The study provides insights into blood dynamics within the heart, potentially improving understanding of circulation efficiency.
• The developed technique and acquired data can serve as a reference for comparing normal and abnormal cardiac flow patterns.
• Results can aid in the calibration of other flow-imaging modalities using a velocity-encoding standard.