Comparison of a Point-of-Care Platelet Function Testing to Light Transmission Aggregometry in Patients Undergoing Percutaneous Coronary Intervention Pretreated With Aspirin and Clopidogrel

Background: Emerging data suggest that many patients are nonresponsive or partially responsive to antiplatelet therapy. In this study, we compared the point-of-care platelet function analysis (PlateletWorks) to the traditional light transmission aggregometry (LTA) in patients taking aspirin and clopidogrel. Methods: A prospective study of 48 patients on chronic aspirin and clopidogrel therapy who were scheduled for percutaneous coronary intervention was conducted. Patients' blood samples were pretreated with either adenosine diphosphate (ADP) 5 mu M, ADP 20 mu M, arachidonic acid (AA), or EDTA. Analysis of platelet aggregation was performed using the PlateletWorks and LTA platforms. Pearson correlation was used to analyze the relationship between the variables, and paired-samples t test assessed the agreement between the results. Results: A significant correlation between PlateletWorks and LTA was found for all 3 variables P <= 0.001 (AA, R-2 = 0.81; ADP 5 mu M, R-2 = 0.60; ADP 20 mu M, R-2 = 0.48). Paired-samples t tests were significant and showed a strong agreement between these methods (AA, t = 2.69, P = 0.01; ADP 5 mu M, t = 6.68, P < 0.001; ADP 20 mu M, t = -3.02, P = 0.004). Conclusions: These data demonstrated a good correlation between the PlateletWorks and the LTA with regard to platelet function in response to chronic aspirin and clopidogrel therapy. Because PlateletWorks is an easier and faster method for the evaluation of platelet function, it should be used at the point-of-care setting in patients with coronary artery disease undergoing percutaneous coronary intervention who were being treated with oral antiplatelet therapy.