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Figure 1 | Thrombosis Journal

Figure 1

From: Comparison of VerifyNow-P2Y12 test and Flow Cytometry for monitoring individual platelet response to clopidogrel. What is the cut-off value for identifying patients who are low responders to clopidogrel therapy?

Figure 1

Receiver Operator Characteristic (ROC) curves defining the sensitivity and specificity of the VerifyNow-P2Y 12 test in patients receiving antiplatelet therapy. Sensitivity and specificity in discriminating responders from non-responders to treatment was based on the arbitrary definition of positive patients (Low responders to clopidogrel; n = 6) and negative patients (High plus Intermediate responders to clopidogrel; n = 46) based on the percentage of platelets exhibiting CD62P expression and PAC-1 binding after stimulation in the presence of PG E1. The two curves shown here, for results expressed as PRU (absolute P2Y12 Reaction Unit) and % of inhibition (% inhibition), respectively, define cut-off values of PRU > 213 and ≤ 15% inhibition, as those giving the highest accuracy (minimal false negative and positive results) in the VerifyNow-P2Y12 test.

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