[Glossary] PW mode measurement

The glossary of “Auto Measure”

• HR (bpm)：Heart rate
• PSV (cm/s)：Peak systolic velocity
• EDV (cm/s)：End diastolic velocity
• PI：Pulsatility index (of Gosling)
  • PI = (PSV–EDV)/TAV Max
• RI：Resistance index (of Pourcelot)
  • RI = (PSV–EDV)/PSV
• VTI (cm)：Velocity-time integral
  • VTI = ∫ [(Upper Velocity + Lower Velocity) / 2] dt
• TAV Max (cm/s)：The maximum of time-averaged velocity
  • TAV Max = VTI Max × HR / 60
  • VTI Max = ∫ [Upper Velocity] dt
• S/B：The average RI of a cycle
• S/D：Systolic/Diastolic Ratio
  • S/D = PSV/EDV
• ACCL (cm/s²)：The acceleration index
  • ACCL = (PSV – EDV)/ACCT
• ACCT (s)：The time from the lowest (EDV) to the highest (PSV)
• VFM (ml/min)：Volume flow per minute
  • VFM = TAV × Diam² × Pi × 15
  • TAV = VTI × HR / 60
• VFM Max (ml/min)：The maximum of volume flow per minute
  • VFM Max = TAV Max × Diam² × Pi × 15
• Diam (mm) ：Diameter

⚠VFM, VFM Max, Diam values will be shown when you are in the frozen state.

The glossary of measure tool “PW V, T, HR”

• T (s)：Time
• HR (bpm)：Heart rate = 60/T
• Range (cm/s)：The range of flow velocity

The glossary of measure tool “RI, S/D”

• PSV (cm/s)：Peak systolic velocity
• EDV (cm/s)：End diastolic velocity
• S/D：Systolic/Diastolic Ratio
  • S/D = PSV/EDV
• RI：Resistance index (of Pourcelot)
  • RI = (PSV–EDV)/PSV

The glossary of measure tool “PI”

• PSV (cm/s)：Peak systolic velocity
• D (cm/s)：End diastolic velocity
• Area (cm²)：Blood vessel cross-sectional area
• Diam (mm)：Diameter
• PI：Pulsatility index (of Gosling)
  • PI = (PSV–EDV)/TAV Max
  • TAV Max = VTI Max × HR / 60
• TAV Max (cm/s)：The maximum of time-averaged velocity
  = VTI * (HR/60)
• VFM Max (ml/min)：The maximum of volume flow per minute
  = TAV Max * (Diam)² * Pi * 15

The glossary of measure tool “VTI”

• VTI (cm)：Velocity-time integral
• SV (ml)：Stroke Volume = Pi * [(LVOT Diam)/2]² * VTI

The glossary of measure tool “E/A Ratio”

• E Vel. (cm/s): E wave velocity
• A Vel. (cm/s): A wave velocity
• E/A Ratio: Ratio of E- to A-wave velocities
• DT (ms): Deceleration time of the E wave
• DT Slope (cm/s²): Deceleration Slope
  • DT Slope = E Velocity / (DT / 1000)

• Vmax (cm/s)：Maximum Velocity
• Max PG (mmHg)：Maximum Pressure Gradient = 4 * (Vmax/100)²