title: Noninvasive measurement of pressure gradient across a coronary stenosis using phase contrast (PC)-MRI: A feasibility study.
abstract: To investigate the feasibility of blood pressure difference measurement, ΔP, across the coronary artery using phase contrast (PC)-MRI for potential noninvasive assessment of the functional significance of coronary artery stenosis.
  
  
  
  Three-directional velocities in the coronary arteries acquired using 2D-PC-MRI were used with the Navier-Stokes equations to derive ΔP. Repeat phantom studies were performed to assess the reproducibility of flow velocity and ΔP. ΔP derived using PC-MRI (ΔPMR) and that obtained using pressure transducer (ΔPPT) were compared. Reproducibility of coronary flow velocity was assessed in healthy controls (n = 11). Patients with suspected coronary artery disease (n = 6) were studied to evaluate the feasibility of ΔPMRmeasurement across a coronary stenosis.
  
  
  
  Phantom: Good overall reproducibility of flow velocity and ΔP measurements and excellent correlation (ΔPMRvs ΔPPT) was observed: intraclass correlation (ICC) of 0.95(Vz), 0.72(Vx), 0.73(Vy), and 0.87(ΔPMR) and R2= 0.94, respectively. Human: Good reproducibility of coronary flow velocity was observed: ICC of 0.94/0.95(Vz), 0.76/0.74(Vx), and 0.80/0.77(Vy) at cardiac phase 1/2. Significant (p = 0.025) increase in ΔPMRwas observed in patients (6.40 ± 4.43 mmHg) versus controls (0.70 ± 0.57 mmHg).
  
  
  
  ΔPMRin the coronary arteries is feasible. Upon further validation using the invasive measure, ΔPMRhas the potential for noninvasive assessment of coronary artery stenosis. Magn Reson Med 77:529-537, 2017. © 2016 International Society for Magnetic Resonance in Medicine.
authors.affiliation: Biomedical Imaging Research Institute, Department of Biomedical Sciences, Cedars-Sinai Medical Center, Los Angeles, California, USA.|Department of Bioengineering, University of California, Los Angeles, California, USA.
authors.forename: Zixin
authors.initials: Z
authors.lastname: Deng
authors.affiliation: Biomedical Imaging Research Institute, Department of Biomedical Sciences, Cedars-Sinai Medical Center, Los Angeles, California, USA.
authors.forename: Zhaoyang
authors.initials: Z
authors.lastname: Fan
authors.affiliation: Division of Cardiology, Severance Cardiovascular Hospital, Seoul, South Korea.
authors.forename: Sang-Eun
authors.initials: SE
authors.lastname: Lee
authors.affiliation: Biomedical Imaging Research Institute, Department of Biomedical Sciences, Cedars-Sinai Medical Center, Los Angeles, California, USA.
authors.forename: Christopher
authors.initials: C
authors.lastname: Nguyen
authors.affiliation: Biomedical Imaging Research Institute, Department of Biomedical Sciences, Cedars-Sinai Medical Center, Los Angeles, California, USA.
authors.forename: Yibin
authors.initials: Y
authors.lastname: Xie
authors.affiliation: Biomedical Imaging Research Institute, Department of Biomedical Sciences, Cedars-Sinai Medical Center, Los Angeles, California, USA.
authors.forename: Jianing
authors.initials: J
authors.lastname: Pang
authors.affiliation: Siemens Healthcare R&D, Los Angeles, USA.
authors.forename: Xiaoming
authors.initials: X
authors.lastname: Bi
authors.affiliation: Biomedical Imaging Research Institute, Department of Biomedical Sciences, Cedars-Sinai Medical Center, Los Angeles, California, USA.
authors.forename: Qi
authors.initials: Q
authors.lastname: Yang
authors.affiliation: Department of Radiology, Severance Hospital, Seoul, South Korea.
authors.forename: Byoung-Wook
authors.initials: BW
authors.lastname: Choi
authors.affiliation: Division of Cardiology, Severance Cardiovascular Hospital, Seoul, South Korea.
authors.forename: Jung-Sun
authors.initials: JS
authors.lastname: Kim
authors.affiliation: Biomedical Imaging Research Institute, Department of Biomedical Sciences, Cedars-Sinai Medical Center, Los Angeles, California, USA.
authors.forename: Daniel
authors.initials: D
authors.lastname: Berman
authors.affiliation: Division of Cardiology, Severance Cardiovascular Hospital, Seoul, South Korea.
authors.forename: Hyuk-Jae
authors.initials: HJ
authors.lastname: Chang
authors.affiliation: Biomedical Imaging Research Institute, Department of Biomedical Sciences, Cedars-Sinai Medical Center, Los Angeles, California, USA.|Department of Bioengineering, University of California, Los Angeles, California, USA.|Department of Medicine, University of California, Los Angeles, California, USA.
authors.forename: Debiao
authors.initials: D
authors.lastname: Li
mesh_terms: D000368:Aged; D001783:Blood Flow Velocity; D001794:Blood Pressure; D001795:Blood Pressure Determination; D023921:Coronary Stenosis / Q000000981:diagnostic imaging* / Q000503:physiopathology*; D005240:Feasibility Studies; D005260:Female; D006801:Humans; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D018810:Magnetic Resonance Angiography / Q000379:methods*; D008297:Male; D008875:Middle Aged; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D012815:Signal Processing, Computer-Assisted; D014655:Vascular Resistance
keywords: coronary artery disease (CAD); coronary pressure gradient; fractional flow reserve (FFR); magnetic resonance imaging (MRI); phase-contrast MRI (PC-MRI); relative pressure difference estimation