PSV	Vr
<50% stenosis	<180 cm/s	<2.5
>50% stenosis	>180 cm/s	>2.5
>70% stenosis	>300 cm/s
For patients suffering from rest pain or non-healing ulceration; a lower PSV >240 cm/s is the threshold for consideration of re-invention.
Significant decrease in ABI >0.15 was also useful to predict restenosis.