Diagnostic Criteria for Transplant Renal Artery Stenosis

Diagnostic Significance of Elevated PSV

A PSV threshold of 200 cm/s has been reported to have a sensitivity of 73-91% and specificity of 75-96% for detecting renal artery stenosis of ≥60% in native kidneys, according to the American College of Radiology 1
Higher PSV thresholds (≥300 cm/s) have been suggested to improve specificity for detecting hemodynamically significant stenosis, as per the American College of Radiology 1

Renal artery ratio (RAR) is a useful additional criterion, with a threshold value of 3.5 commonly used to identify significant stenosis, as recommended by the American College of Radiology 1
For stented renal arteries, higher thresholds apply - PSV of at least 395 cm/s or RAR of at least 5.1 is more predictive of significant in-stent stenosis, according to the American College of Radiology 1
Resistive index (RI) provides prognostic information, with RI >0.80 reported as a negative prognostic sign for response to revascularization, as per the American College of Radiology 1
Patients with RI >0.80 at 3 months post-transplantation have a 47% risk of developing chronic allograft nephropathy compared to 9% in those with RI <0.80, as stated by a medical guideline society 2