LVOT diameter
Recording:
  • 2D parasternal long-axis view
  • Zoom mode
  • Adjust gain to optimize the blood tissue interface
Measurement:
  • Inner edge to inner edge
  • Mid-systole
  • Parallel and adjacent to the aortic valve or at the site of velocity measurement
  • Diameter is used to calculate a circular CSA
LVOT velocity
Recording:
  • Pulsed-wave Doppler
  • Apical long axis or five-chamber view
  • Sample volume positioned just on LV side of valve and moved carefully into the LVOT if required to obtain laminar flow curve
  • Velocity baseline and scale adjusted to maximize size of velocity curve
  • Time axis (sweep speed) 100 mm/s
  • Low wall filter setting
  • Smooth velocity curve with a well-defined peak and a narrow velocity range at peak velocity
Measurement:
  • Maximum velocity from peak of dense velocity curve
  • VTI traced from modal velocity
AS jet velocity
Recording:
  • CW Doppler (dedicated transducer)
  • Multiple acoustic windows (e.g. apical, suprasternal, right parasternal, etc)
  • Decrease gains, increase wall filter, adjust baseline, and scale to optimize signal
  • Gray scale spectral display with expanded time scale
  • Velocity range and baseline adjusted so velocity signal fits but fills the vertical scale
Measurement:
  • Maximum velocity at peak of dense velocity curve
  • Avoid noise and fine linear signals
  • VTI traced from outer edge of dense signal curve
  • Mean gradient calculated from traced velocity curve
  • Report window where maximum velocity obtained
Valve anatomy
Recording:
  • Parasternal long- and short-axis views
  • Zoom mode
Measurement:
  • Identify number of cusps in systole, raphe if present
  • Assess cusp mobility and commisural fusion
  • Assess valve calcification

CSA: Cross-sectional area, VTI: Velocity time integral.