Evaluation of aortic stenosis severity using 4D flow jet shear layer detection for the measurement of valve effective orifice area

Julio Garcia*, Michael Markl, Susanne Schnell, Bradley Allen, Pegah Entezari, Riti Mahadevia, S Chris Malaisrie, Philippe Pibarot, James Carr, Alex J Barker

*Corresponding author for this work

Research output: Contribution to journalArticle

16 Scopus citations

Abstract

Aims: The objective of this study was to evaluate the potential of 4D flow MRI to assess valve effective orifice area (EOA) in patients with aortic stenosis as determined by the jet shear layer detection (JSLD) method. Methods and Results: An in-vitro stenosis phantom was used for validation and in-vivo imaging was performed in 10 healthy controls and 40 patients with aortic stenosis. EOA was calculated by the JSLD method using standard 2D phase contrast MRI (PC-MRI) and 4D flow MRI measurements (EOAJSLD-2D and EOAJSLD-4D, respectively). As a reference standard, the continuity equation was used to calculate EOA (EOACE) with the 2D PC-MRI velocity field and compared to the EOAJSLD measurements. The in-vitro results exhibited excellent agreement between flow theory (EOA=0.78cm2) and experimental measurement (EOAJSLD-4D=0.78±0.01cm2) for peak velocities ranging from 0.9 to 3.7m/s. In-vivo results showed good correlation and agreement between EOAJSLD-2D and EOACE (r=0.91, p<0.001; bias: -0.01±0.38cm2; agreement limits: 0.75 to -0.77cm2), and between EOAJSLD-4D and EOACE (r=0.95, p<0.001; bias: -0.09±0.26cm2; limits: 0.43 to -0.62cm2). Conclusion: This study demonstrates the feasibility of measuring EOAJSLD using 4D flow MRI. The technique allows for optimization of the EOA measurement position by visualizing the 3D vena contracta, and avoids potential sources of EOACE measurement variability.

Original languageEnglish (US)
Pages (from-to)891-898
Number of pages8
JournalMagnetic Resonance Imaging
Volume32
Issue number7
DOIs
StatePublished - Sep 2014

Keywords

  • 4D flow MRI
  • Aortic stenosis
  • Effective orifice area
  • Jet shear layer

ASJC Scopus subject areas

  • Biophysics
  • Biomedical Engineering
  • Radiology Nuclear Medicine and imaging

Fingerprint Dive into the research topics of 'Evaluation of aortic stenosis severity using 4D flow jet shear layer detection for the measurement of valve effective orifice area'. Together they form a unique fingerprint.

  • Cite this