Four-dimensional flow assessment of pulmonary artery flow and wall shear stress in adult pulmonary arterial hypertension: results from two institutions

Magn Reson Med. 2015 May;73(5):1904-13. doi: 10.1002/mrm.25326. Epub 2014 Jun 27.


Purpose: To compare pulmonary artery flow using Cartesian and radially sampled four-dimensional flow-sensitive (4D flow) MRI at two institutions.

Methods: Nineteen healthy subjects and 17 pulmonary arterial hypertension (PAH) subjects underwent a Cartesian 4D flow acquisition (institution 1) or a three-dimensional radial acquisition (institution 2). The diameter, peak systolic velocity (Vmax), peak flow (Qmax), stroke volume (SV), and wall shear stress (WSS) were computed in two-dimensional analysis planes at the main, right, and left pulmonary artery. Interobserver variability, interinstitutional differences, flow continuity, and the hemodynamic measurements in healthy and PAH subjects were assessed.

Results: Vmax, Qmax, SV, and WSS at all locations were significantly lower (P < 0.05) in PAH compared with healthy subjects. The limits of agreement were 0.16 m/s, 2.4 L/min, 10 mL, and 0.31 N/m(2) for Vmax, Qmax, SV, and WSS, respectively. Differences between Qmax and SV using Cartesian and radial sequences were not significant. Plane placement and acquisition exhibited isolated, site-based differences between Vmax and WSS.

Conclusions: 4D flow MRI was used to detect differences in pulmonary artery hemodynamics for PAH subjects. Flow and WSS in healthy and PAH subject cohorts were similar between Cartesian- and radial-based 4D flow MRI acquisitions with minimal interobserver variability.

Keywords: 4D flow MRI; pulmonary hypertension; wall shear stress.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Aged
  • Blood Flow Velocity / physiology
  • Female
  • Hemodynamics / physiology
  • Humans
  • Hypertension, Pulmonary / physiopathology*
  • Image Processing, Computer-Assisted / methods*
  • Imaging, Three-Dimensional / methods*
  • Magnetic Resonance Angiography / methods*
  • Male
  • Middle Aged
  • Observer Variation
  • Pulmonary Artery / physiology*
  • Pulmonary Embolism / physiopathology
  • Reference Values
  • Scleroderma, Systemic / physiopathology
  • Sensitivity and Specificity
  • Shear Strength
  • Stroke Volume / physiology
  • Systole / physiology