Complete versus partial distal embolic protection during renal artery stenting

The aim of this study was to evaluate whether complete embolic protection is superior to partial embolic protection for preservation of kidney function during renal artery angioplasty and stenting.

Renal artery angioplasty and stenting (RAAS) is a common treatment for atherosclerotic renal artery stenosis. However, RAAS may be complicated by peri-procedural loss of kidney function.

In total, 44 patients were randomized to embolic protection devices (EPD) use; 25 complete and 19 partial embolic protection. These patients were further randomized to receive abciximab (n = 23) or placebo (n = 21). [corrected] MDRD glomerular filtration rate (GFR), was used as the primary measure of renal function. Creatinine was measured by a modified Jaffe reaction using the IDMS-traceable assay. The primary endpoint was the percent change in estimated glomerular filtration rate (eGFR) 1 month following stent placement.

There was no difference in percent change eGFR at 1 month between complete or partial protection (-4 +/- 25 vs. +3 +/- 30, P = 0.45). Abciximab was associated with a net improvement in eGFR when compared with placebo (+0.5 +/- 27 vs. -11 +/- 20, P = 0.04). On subgroup analysis, the use of abciximab was associated with significantly improved eGFR in the partial distal embolic protection group (+14 +/- 33 vs. -17 +/- 13 %, P = 0.018) but not in the complete distal embolic protection group (+2.5 +/- 26 vs. -11 +/- 24, P = 0.42), however, there was no interaction between completeness of protection and abciximab on eGFR (P = ns). Capture of embolic material was more likely with complete protection when compared with those receiving partial protection (51% vs. 21%, P < 0.05).

Complete protection was superior to partial protection for the capture of athermanous debris during renal artery stenting. However, this was not associated with improved renal function. Importantly, Abciximab conferred a benefit for renal function that was independent of the degree of embolic protection.