Which is the most impoant sign of significance of renal aery stenosis on an angiogram?
The most impoant sign of significant renal aery stenosis on an angiogram is presence of bridging collaterals. Other signs of hemodynamically significant aerial stenosis are post stenotic dilation, pressure gradient >10mmHg or ipsilateral renal vein renin hypersecretion. Ref: Essentials of Surgery: Scientific Principles and Practice By Lazar J. Greenfield, page 560; Computed Body Tomography With Mri Correlation, Volume 1 By Joseph K. T. Le page 1288
Presence of collaterals
A percentage diameter stenosis > 70%
Post-stenotic dilatation of the renal aery
A systolic pressure gradient > 20 mm Hg across the lesion