Renal embolic protection devices improve blood flow after stenting for atherosclerotic renal artery stenosis.

OBJECTIVES

We sought to measure angiographic renal frame counts (RFC), as a quantitative angiographic assessment of renal blood flow, to evaluate microvascular compromise due to atheroembolism associated with RAS.

BACKGROUND

Atheroembolism associated with renal artery stenting (RAS) has been implicated as a cause for worsening renal function following successful intervention. Use of a distal embolic protection device (EPD) during RAS has been shown to be safe with debris capture in a high percentage of cases. However, objective benefit for renal function with EPD has been difficult to demonstrate.

METHODS

A control group of 30 consecutive patients (33 kidneys) who underwent RAS without EPD were compared with 33 consecutive patients (33 kidneys) who underwent RAS with EPD using RFC measurement.

RESULTS

The prestent and poststent mean RFC for the control group was 30.4 ± 12.1 vs. 23.7 ± 9.9 (P = 0.002) and for the EPD group it was 42.6 ± 12.6 vs. 28.3 ± 9.2 (P < 0.0001). The EPD group had a greater improvement in renal blood flow, manifested by a greater reduction of the RFC (Δ RFC) 14.2 ± 15.2 vs. 6.7 ± 11.7 (P = 0.03) compared with the control group.

CONCLUSIONS

The use of an EPD was associated with a much larger improvement in renal blood flow (lower RFC) following RAS. This suggests that EPD's may be effective in preventing renal atheroembolic injury and that a controlled trial measuring the impact of EPD's on renal blood flow following RAS should be performed.