Platelet reactivity after clopidrogrel treatment assessed with point-of-care analysis (MEA) and early drug-eluting stent thrombosis.
Does platelet reactivity to clopidogrel assessed with multiple electrode platelet aggregometry (MEA) correlate with the risk of early drug-eluting stent thrombosis?
2/07-2/08, 1608 patients
Before PCI, all patients received 600 mg clopidogrel. The ADP-induced platelet aggregation was assessed in whole blood with a MEA.
The primary end point was definite ST at 30 days.
Compared with normal responders (n = 1,285), low responders (MEA upper qunitile, n = 323) had a significantly higher risk of:
definite ST within 30 days (2.2% vs. 0.2%; odds ratio [OR]: 9.4; 95% confidence interval [CI]: 3.1 to 28.4; p < 0.0001)
Mortality rates were 1.2% in low versus 0.4% in normal responders (OR: 3.2; 95% CI: 0.9 to 11.1; p = 0.07).
Composite of death or ST was higher in low versus normal responders (3.1% vs. 0.6%; OR: 5.1; 95% CI: 2.2 to 11.6; p < 0.001).
Low response to clopidogrel assessed with MEA is significantly associated with an increased risk of ST. Further studies are warranted to evaluate the ability of MEA to guide antiplatelet therapy in patients undergoing PCI.