E/A ratio (E / A ratio)

Last edited 05/2018

The E/A ratio

• when flow across the MV is assessed with PW Doppler, two waves are characteristically seen
  • represent passive filling of the ventricle (early [E] wave)
  • active filling with atrial systole (atrial [A] wave)
    
    
  • classically, the E-wave velocity is slightly greater than that of the A wave
    • however, in conditions that limit the compliance of the LV, two abnormalities are possible:
      • reversal
        • the A wave is greater than the E wave
        • indicates slow filling caused by older age, hypertension, left ventricular hypertrophy (LVH), or diastolic dysfunction
      • exaggeration of normal
        • a tall, thin E wave with a small or absent A wave
        • indicates restrictive cardiomyopathy, constrictive pericarditis, or infiltrative cardiac disease (eg, amyloidosis)