Effects of stent coating on platelets and endothelial cells after intracoronary stent implantation

Background: Adhesion molecules are known to be important in the regulation of endothelial cell and platelet functions. Increased platelets P-selectin expression is a marker of stent thrombosis after uncoated stent placement. Hypothesis: The aim of this study was to compare the effects of intracorona ry placement of phosphorylcholine (PC)coated, versus heparin-coated, versus uncoated stents on platelets and endothelial activity. Methods: Thirty patients (age 55 +/- 10, 27 men) with significant proximal left anterior descending coronary artery stenoses were randomized to electi ve implantation of PC-coated, versus heparin-coated, versus uncoated stents . Following stent placement, intravenous heparin and aspirin plus ticlopidi ne were administered. Venous plasma soluble E-selectin. sP-selectin, and in tercellular adhesion molecule-1 levels were measured before the procedure a nd 24 and 48 h thereafter as markers of platelet and endothelial cell activ ation. Patients were excluded if they had a disease known to influence plat elet and endothelial cell function. Results: Plasma sP-selectin levels decreased significantly after implantati on of PC- and heparin-coated stents (p = 0.04:), but remained unchanged in patients randomized to uncoated stents. Plasma sE-selectin levels increased significantly after uncoated stent placement (p = 0.01) and remained uncha nged after coated stent implantation. Conclusion: In patients treated with combined antiplatelet therapy implanta tion of PC- and heparin-coated stents decreased platelet activity without a ctivating endothelial cells, whereas placement of uncoated stents led to en dothelial activation without changing platelet activity. These results sugg est that PC-coated and heparin-coated stents may be advantageous in limitin g thrombotic complications.