Table 8.

Prosthetic aortic valve stenosis criteria^a

Parameter	Normal	Possible stenosis	Significant stenosis
Peak velocity (m/s)b	<3	3–4	>4
Mean gradient (mmHg)b	<20	20–35	>35
Doppler velocity index	≥0.30	0.29–0.25	<0.25
Effective orifice area (cm2)	>1.2	1.2–0.8	<0.80
Contour of the jet velocity through the prosthetic valve	Triangular, early peaking	Triangular to intermediate	Rounded, symmetrical contour
Acceleration time (ms)	<80	80–100	>100

^aIn conditions of normal or near normal stroke volume (50–70 mL).

^bThese parameters are more affected by flow, including concomitant aortic regurgitation.