Figure 1.
Representative ADP aggregation curves demonstrating the effect of clopidogrel treatment.
Platelet aggregation was performed on PGE1 pretreated (right side) and non-pretreated (left side) platelet rich plasma (PRP). The upper and lower panels of the figure show results with PRP from a clopidogrel responder and a non-responder patient, respectively. Aggregation curves with samples from controls not taking antiplatelet medication are also demonstrated on each panel.
Figure 2.
Correlation of ADP-induced aggregation in platelet rich plasma pre-treated with PGE1 or with P2Y1 inhibitor.
Platelet rich plasma was pre-treated with 0.31 µM PGE1 or 1 mM adenosine 3’, 5’-diphosphate (A3P5P), a P2Y1 receptor inhibitor, for 3 min at 37 °C. Broken lines represent 95% confidence interval, r=0.89, p=0.001.
Figure 3.
Aspirin therapy does not influence the P2Y12 specific ADP(PGE1) platelet aggregation test.
ADP-induced aggregation in PGE1 pre-treated platelet rich plasma of controls (solid circles) and patients on aspirin therapy (open squares). Horizontal lines represent medians, the long broken line indicates the lower limit of reference interval. n.s.: non-significant.
Figure 4.
Results of ADP-induced platelet aggregation.
Platelet aggregation was induced by 5 µM (A) and 20 µM ADP (B) in the platelet rich plasma of controls (solid circles) and patients on clopidogrel monotherapy (open circles). Horizontal lines represent medians, the long broken line indicates the lower limit of reference interval. NR: non-responder.
Figure 5.
Results of VerifyNow P2Y12 and VASP phosphorylation tests.
VerifyNow P2Y12 (A) and VASP phosphorylation (B) tests were performed in the control group (solid circles) and in the group of patients on clopidogrel therapy (open circles). Horizontal lines represent medians, the long broken line indicates the lower limit of reference interval, the long dotted line on panel B shows the cut-off for clopidogrel resistance established in clinical studies [4,5,12]. NR: non-responder, WR: weak responder, SR: strong responder.
Figure 6.
Results of P2Y12 specific ADP(PGE1) platelet aggregation test.
P2Y12 specific ADP aggregation test was performed in the control group (solid circles) and in the group of patients on clopidogrel therapy (open circles). Results are demonstrated as scatterograms (A) and histograms (B). Horizontal lines on panel A represent medians, the long broken line indicates the lower limit of reference interval. NR: non-responder, WR: weak responder, SR: strong responder.
Figure 7.
Correlation of VASP phosphorylation and P2Y12 specific ADP(PGE1) aggregation tests in clopidogrel treated patients.
Broken lines represent the lower limit of reference intervals, dotted lines separate presumed strong responders from weak responders. NR: non-responder, WR: weak responder, SR: strong responder.