Severity	Aortic jet velocity (m per second)	Mean gradient (mm Hg)	Aortic valve area (cm2)
Normal	< 2.5	—	3 to 4
Mild	2.5 to 2.9	< 25	1.5 to 2
Moderate	3 to 4	25 to 40	1 to 1.5
Severe	> 4	> 40	< 1