Relationship between Clopidogrel-Induced Platelet P2Y12 Inhibition and Stent Thrombosis or Myocardial Infarction after Percutaneous Coronary Intervention : A Case-Control Study

• Aims: Platelet inhibition levels were investigated in patients with previous angiographically confirmed stent thrombosis (ST), myocardial infarction (MI) and controls.Methods and Results: Using The Swedish Coronary Angiography and Angioplasty Registry we identified patients with angiographically confirmed ST (n=48) or MI (n=30) while on dual antiplatelet therapy within 6 months of percutaneous coronary intervention (PCI) and matched control patients (n=78) with none of these events in the same setting. On-clopidogrel platelet reactivity was measured with VerifyNow™ P2Y12 and vasodilator stimulated phosphoprotein phosphorylation (VASP-P) assay.The mean P2Y12 reaction units (PRU) was higher (246.8 ± 75.9 vs. 200.0 ± 82.7, p=0.001) in ST patients compared to controls. The optimal cut-off for ST was ≥222 PRU (area under the curve 0.69, p<0.0001) in a receiver operating characteristics (ROC) analysis, which was identical to the cut-off level defined as the proportion of controls below the 30th percentile of P2Y12 inhibition distribution in patients with ST.  The cut-off level resulted in 70.2% sensitivity and 67.3% specificity. There was no significant difference in mean PRU but a higher device-reported % inhibition (45.1 ± 23.8 vs 32.1 ± 23.2, p=0.04) in patients with MI compared to controls. Results with the VASP-P assay were not related to the occurrence of ST or MI.Conclusion: Stent thrombosis was associated with high on-clopidogrel platelet reactivity measured with VerifyNow™. Spontaneous MI in stented patients on clopidogrel treatment was not. There was, however, a substantial overlap in clopidogrel platelet reactivity response between patients with and without on-treatment ST.

Subject headings

MEDICIN OCH HÄLSOVETENSKAP  -- Klinisk medicin -- Kardiologi (hsv//swe)

MEDICAL AND HEALTH SCIENCES  -- Clinical Medicine -- Cardiac and Cardiovascular Systems (hsv//eng)

Keyword

clopidogrel

acute coronary syndromes

coronary artery disease

stent thrombosis

VerifyNow™

VASP

clopidogrel poor response

klopidogrel

akuta koronara syndrom

hjärtinfarkt

stenttrombos

Cardiology

Kardiologi

Kardiologi

Cardiology

Publication and Content Type

ref (subject category)

art (subject category)