Duplex ultrasonography in assessing restenosis of renal artery stents

Cardiovasc Intervent Radiol. Nov-Dec 1999;22(6):475-80. doi: 10.1007/s002709900435.


Purpose: To determine the accuracy and optimal threshold values of duplex ultrasonography (US) in assessing restenosis of renal artery stents.

Methods: Twenty-four consecutive patients with 33 renal arteries that had previously been treated with placement of a Palmaz stent underwent duplex US prior to intraarterial digital subtraction angiography (DSA), which was the reference standard. Diagnostic accuracy of in-stent peak systolic velocity (PSV) and reno-aortic ratio (RAR = PSV renal stent/PSV aorta) in detecting > 50% in-stent restenosis were evaluated by the receiver operating characteristic curve. Sensitivity and specificity were determined using the optimal threshold values, and using published threshold values: RAR > 3.5 and in-stent PSV > 180 cm/sec.

Results: Six examinations were technically inadequate. Nine stents had residual or restenosis > 50% at DSA. The two duplex parameters were equally accurate since areas under the curves were similar (0.943). With optimal threshold values of 226 cm/sec for PSV and 2.7 for RAR, sensitivities and specificities were 100% and 90%, and 100% and 84%, respectively. Using the published duplex criteria resulted in sensitivities and specificities of 100% and 74% for PSV, and 50% and 89% for RAR.

Conclusion: Duplex US is a sensitive modality for detecting in-stent restenosis if laboratory-specific threshold values are used.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aged
  • Angiography, Digital Subtraction
  • Female
  • Humans
  • Male
  • Prospective Studies
  • ROC Curve
  • Recurrence
  • Renal Artery / diagnostic imaging
  • Renal Artery Obstruction / diagnostic imaging*
  • Renal Artery Obstruction / therapy*
  • Sensitivity and Specificity
  • Stents*
  • Ultrasonography, Doppler, Duplex*