Platelet activation in patients with atherosclerotic renal artery stenosis undergoing stent revascularization.

BACKGROUND AND OBJECTIVES: Soluble CD40 ligand (sCD40L) is a marker of platelet activation; whether platelet activation occurs in the setting of renal artery stenosis and stenting is unknown. Additionally, the effect of embolic protection devices and glycoprotein IIb/IIIa inhibitors on platelet activation during renal artery intervention is unknown. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: Plasma levels of sCD40L were measured in healthy controls, patients with atherosclerosis without renal stenosis, and patients with renal artery stenosis before, immediately after, and 24 hours after renal artery stenting. RESULTS: Soluble CD40L levels were higher in renal artery stenosis patients than normal controls (347.5 ± 27.0 versus 65.2 ± 1.4 pg/ml, P < 0.001), but were similar to patients with atherosclerosis without renal artery stenosis. Platelet-rich emboli were captured in 26% (9 of 35) of embolic protection device patients, and in these patients sCD40L was elevated before the procedure. Embolic protection device use was associated with a nonsignificant increase in sCD40L, whereas sCD40L declined with abciximab after the procedure (324.9 ± 42.5 versus 188.7 ± 31.0 pg/ml, P = 0.003) and at 24 hours. CONCLUSIONS: Atherosclerotic renal artery stenosis is associated with platelet activation, but this appears to be related to atherosclerosis, not renal artery stenosis specifically. Embolization of platelet-rich thrombi is common in renal artery stenting and is inhibited with abciximab.