Related Experiment Video
Updated: Jul 1, 2025
11:16
In vitro Assessment of Aortic Regurgitation Using Four-Dimensional Flow Magnetic Resonance Imaging
Published on: February 25, 2022
3.3K
Validation of 2D flow MRI for helical and vortical flows
Zia Mehmood1, Hosamadin Assadi1,2, Ciaran Grafton-Clarke1,3
1Norfolk and Norwich University Hospitals NHS Foundation Trust, Norwich, UK.
Open Heart
|March 8, 2024
Summary
New two-dimensional (2D) phase contrast (PC) methods can quantify blood flow helicity and vorticity in the aortic root. These validated imaging biomarkers show high reproducibility for clinical use.
Area of Science:
- Cardiovascular Imaging
- Biomedical Engineering
- Fluid Dynamics
Background:
- Quantifying blood flow dynamics in the aortic root is crucial for understanding cardiovascular health.
- Existing methods may have limitations in assessing complex flow patterns like helicity and vorticity.
Purpose of the Study:
- To develop and validate two-dimensional (2D) phase contrast (PC) magnetic resonance imaging (MRI) methods for quantifying blood flow helicity and vorticity in the aortic root.
Main Methods:
- Utilized four-dimensional (4D) flow cardiovascular MRI data from healthy controls and patients with heart failure with preserved ejection fraction or aortic stenosis.
- Adapted 4D flow data to simulate 2D PC planes, quantifying flow displacement (FD), systolic flow reversal ratio (sFRR), and rotational angle (RA).
- Assessed helicity and vorticity through visual analysis of flow vectors and quantitative metrics.
Main Results:
- The sFRR demonstrated high accuracy (AUC=0.955) in identifying vortex flow, with a threshold of >8% showing 82% sensitivity and 100% specificity.
- Average late systolic FD (flow eccentricity marker) also showed significant accuracy (AUC=0.909) for vortex flow detection.
- Quantitative metrics (FD, sFRR, ΔsRA) exhibited excellent reproducibility (ICC > 0.92) and strong correlation with manual measurements.
Conclusions:
- Developed 2D PC flow imaging techniques effectively quantify blood flow helicity (ΔRA) and vorticity (FRR) in the aortic root.
- These novel imaging biomarkers of flow helicity and vorticity demonstrate high reproducibility, supporting potential clinical adoption.
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