Platelet activation after stenting with heparin-coated versus noncoated stents.
BACKGROUND
In animal models, heparin coating reduces platelet accumulation induced by coronary stenting. However, reduced platelet activation has never been demonstrated in humans. The purpose of the current study was to investigate the effect of heparin coating on platelet activation after coronary artery stenting.


METHODS
In a prospective, randomized, pilot study of 50 consecutive elective patients, platelet activation was analyzed by measuring aggregation and surface receptor expression before and at 2 hours, 24 hours, 5 days and 30 days after implantation of either heparin-coated or noncoated stents.


RESULTS
There was less platelet activation after implantation of a heparin-coated stent, as indicated by reduced expression at 24 hours of active glycoprotein (GP) IIb/IIIa (10.3 +/- 6.1 vs 6.7 +/- 2.1, P =.014), and total GP IIb/IIIa (382 +/- 101 vs 306 +/- 88, P =.01). A trend at 30 days poststenting of lower total (383 +/- 150 vs 296 +/- 86, P =.07) and active GP IIb/IIIa expression (10.3 +/- 6.9 vs 7.5 +/- 2.9, P =.15) was also observed with the heparin-coated stent). Aggregation and stimulated p-selectin did not differ between stent types.


CONCLUSIONS
Use of a heparin-coated stent in this pilot study of elective patients was associated with primarily less early platelet expression of GP IIb/IIIa. These findings have implications on the risk of subacute thrombosis and deserve further investigation.
Gurbel
Paul A
PA
Sinai Hospital, Sinai Center for Thrombosis Research, Baltimore, Md 21215, USA. pgurbel@lifebridgehealth.org
Bliden
Kevin P
KP
D000368:Aged; D000925:Anticoagulants / Q000008:administration & dosage*; D001241:Aspirin / Q000008:administration & dosage; D015415:Biomarkers / Q000097:blood; D001792:Blood Platelets / Q000187:drug effects / Q000502:physiology; D054641:Dual Specificity Phosphatase 2; D005260:Female; D005434:Flow Cytometry; D006493:Heparin / Q000008:administration & dosage*; D006801:Humans; D008297:Male; D019007:P-Selectin / Q000097:blood; D010865:Pilot Projects; D015539:Platelet Activation; D010974:Platelet Aggregation / Q000187:drug effects; D019039:Platelet Glycoprotein GPIIb-IIIa Complex / Q000378:metabolism*; D040201:Platelet Membrane Glycoprotein IIb / Q000097:blood; D011446:Prospective Studies; D054648:Protein Phosphatase 2; D017027:Protein Tyrosine Phosphatases / Q000097:blood; D015607:Stents
D000925:Anticoagulants; D015415:Biomarkers; D019007:P-Selectin; D019039:Platelet Glycoprotein GPIIb-IIIa Complex; D040201:Platelet Membrane Glycoprotein IIb; D006493:Heparin; D054648:Protein Phosphatase 2; C517032:DUSP2 protein, human; D054641:Dual Specificity Phosphatase 2; D017027:Protein Tyrosine Phosphatases; D001241:Aspirin