ORIGINAL ARTICLESHigher platelet activity is present in patients with restenosis after percutaneous coronary intervention compared with patients with an occlusion of coronary artery bypass graftOsmancik, Pavel Pa; Bednar, Frantisekb; Pavkova, Leonaa; Tousek, Petra; Stros, Petra; Jirasek, KarelbAuthor Information aCardiocenter, Department of Cardiology, Czech Republic bCardiocenter, Department of Cardiac Surgery, 3rd Medical School, Charles University and University Hospital Kralovske Vinohrady Prague, Czech Republic Received 3 March, 2007 Revised 17 August, 2007 Accepted 18 August, 2007 Correspondence to Pavel P. Osmancik, MD, PhD, Cardiocenter, Department of Cardiology, 3rd Medical School, Charles University and University Hospital Kralovske Vinohrady, Srobarova 50, 100 34 Prague 10, Czech Republic Tel: +420 721544447; fax: +420 267162621; e-mail: firstname.lastname@example.org Blood Coagulation & Fibrinolysis: December 2008 - Volume 19 - Issue 8 - p 807-812 doi: 10.1097/MBC.0b013e3283169223 Buy Metrics Abstract The aim of the study was to compare platelet activity between patients with an occlusion of bypass graft after coronary artery bypass graft surgery and restenosis after percutaneous coronary intervention (PCI); that is, between patients with reappearance of ischemia after two different kinds of coronary revascularization. Thirty patients were studied in a cross-sectional designed study. Fifteen of them were patients with the worst bypass graft patency from Prague-4 study (control protocol-driven coronary angiography performed at 1 year after surgery; originally 47 bypass grafts implanted, 94% of venous grafts occluded). The remaining 15 were patients with restenosis 3–12 months after PCI. Blood samples were drawn at least 12 weeks after coronary angiography. Platelet activity was determined by membrane expression of P-selectin (CD62P, % of positive cells) by flow cytometry, aggregability by ADP aggregometry. Data are expressed as mean ± SEM. Both groups were similar with respect to age, BMI and presence of diabetes mellitus. No patient suffered from acute coronary syndrome. P-selectin expression was significantly higher in the patients with restenosis compared with patients with bypass graft occlusion (1.96 ± 0.07 vs. 0.77 ± 0.03, P < 0.001, Wilcoxon test). ADP aggregometry was not different between groups (55.5 ± 1.1 vs. 56.1 ± 0.8, P = NS). Higher platelet activity is present in the patients with restenosis after PCI compared with the patients with the occlusion of bypass graft. Platelet activity play more important role in the development of restenosis after PCI compared with the occlusion of bypass graft after coronary artery bypass graft surgery, at least in the period up to 1 year after revascularization. © 2008 Lippincott Williams & Wilkins, Inc.