|Peak-to-Peak Systolic Gradient (Catherization)||Mean Echo Doppler Gradient (CW)||Peak Instantaneous Echo Doppler Gradient (CW)⁎|
|Mild AS||less than 30 mm Hg||less than 25 mm Hg||less than 40 mm Hg|
|Moderate AS||30 to 50 mm Hg||25 to 40 mm Hg||40 to 70 mm Hg|
|Severe AS||greater than 50 mm Hg||greater than 40 mm Hg||greater than 70 mm Hg|
↵⁎ Gradients obtained from apical window usually most predictive of catheter gradient.