End-Diastolic Velocity (EDV): Doppler velocity at the end of diastole; critically low or reversed values indicate elevated downstream resistance or severe vascular compromise.
End-diastolic velocity (EDV) is the blood flow velocity measured at the end of diastole on spectral Doppler. It reflects downstream vascular resistance. Absent or reversed EDV in the umbilical artery is a critical sign of severe fetal compromise in IUGR. The ICA/CCA ratio (resistivity) and S/D ratio are calculated from PSV and EDV values.