1. Determine coronary rest period
    • Acquire HLA with high temporal resolution (50 phases)
  2. Navigator-gated, free-breathing 3D pulse sequence:
    • Trans-axial slices (from the proximal main pulmonary artery to the middle of the right atrium; entire cardiac coverage if desired).
    • Slice thickness: 1-1.5 mm
    • Spatial resolution in-plane: 1.0 mm or less
    • Slices: typically 50 – 80
    • Adjust trigger delay and acquisition window according to observed coronary artery rest period
    • Parallel acquisition preferred
    • Navigator placed over the right hemi-diaphragm
  3. Optional:
    • Consider contrast to increase vessel conspicuity
    • Breath-hold techniques if poor image quality or if navigators are unavailable or are of poor quality
    • T2-prepared sequence may be useful
Tips and Tricks
  1. Problems identifying coronary rest period:
    • Repeat high temporal resolution 4-ch scan at the correct HR
    • Consider cine scan during free-breathing if HR changes significantly during breath-hold
    • Check during systole with a tight window (<50 ms)
    • As a compromise, scan with longest trigger delay and a tight window (<50 ms)
  2. Coronary rest period may differ between LCA and RCA
  3. High HR (≥ 90bpm): Use shortest scan window possible to minimize blurring
  4. Keep scan times to a sensible limit
  5. Higher spatial resolution equals longer scan times
4-ch view showing the RCA in diastole