Clopidogrel plays a pivotal role in the antithrombotic regimen after percutaneous
intervention with stent implantation. However, response to clopidogrel shows a wide
interindividual variability and a high on-treatment residual ADP-inducible platelet
reactivity has already been associated with an increased risk for adverse events after
coronary stenting. In the present study, platelet reactivity will be determined by 6
different platelet function tests in patients on dual antiplatelet therapy after angioplasty
and stenting for peripheral, coronary and carotid artery disease. One hundred patients
showing high on-treatment residual ADP-inducible platelet reactivity in 2 or more tests will
be randomized to receive either 75mg or 150mg of daily clopidogrel in addition to aspirin for
3 months. The aim of the present study is to investigate the effects of intensified
antithrombotic therapy (150mg clopidogrel + 100mg aspirin daily) versus standard
antithrombotic therapy (75mg clopidogrel + 100mg aspirin daily) in patients with decreased
clopidogrel-mediated platelet inhibition after percutaneous intervention with stent
implantation.