CAN THE RISK FOR ACUTE CARDIAC EVENTS IN ACUTE CORONARY SYNDROME BE INDICATED BY PLATELET MEMBRANE ACTIVATION MARKER P-SELECTIN

Background: P-selectin, an adhesion molecule of the selectin family, i s expressed on the surface of activated thrombocytes by thrombin. The aim of the present study was to assess the predictive value of P-selec tin (estimated by flow cytometric assay) for acute cardiac events in a cute coronary syndrome. Methods: The study consisted of 48 patients wi th acute coronary syndrome and 30 healthy control subjects. After imme diate fixation with 1% paraformaldehyde, 50 mu l of this aliquot was i ncubated with phycoerythrin-CD62-related antigen, and then measured by flow cytometry. The short-term clinical course of the patients was co mpared with their P-selectin values. Results: The average P-selectin v alues in the 30 healthy volunteers was 0.11 +/- 0.20% (range, 0.0-0.5% ). Significant differences were observed between acute cardiac events in patients with unstable angina and high P-selectin values and those with normal P-selectin Values (chi(2)=4.3; P<0.05). Moreover, the angi na patients who experienced acute cardiac events had significantly ele vated P-selectin values (2.1 +/- 2.3%) compared with patients who did not experience acute cardiac events (0.3 +/- 0.4%, P<0.05). The P-sele ctin values were elevated in seven out of 24 patients who suffered acu te myocardial infarction. Seven of the 14 patients with acute coronary syndromes and high P-selectin values required urgent percutaneous tra nsluminal coronary angioplasty (PTCA) and coronary artery bypass graft ing (CABG), or both, otherwise they developed extension of the infarct ion. However, only five of the 34 patients with normal P-selectin valu es required urgent PTCA or CABG. Significant differences were observed in acute cardiac events between the high P-selectin and normal P-sele ctin groups (chi(2)=4.8, P<0.05). Conclusion: High P-selectin values i ndicate activation of platelets and the risk of acute cardiac events i n patients with acute coronary syndrome.