Our first hypothesis is that dose adjustment of aspirin and clopidogrel based on biological monitoring reduces the rate of severe cardiovascular complications compared to a conventional strategy in patients scheduled for drug eluting stent implantation and followed up for one year. Our second hypothesis is that interruption of clopidogrel / Prasugrel after one year of a combined therapy of clopidogrel/Prasugrel and aspirin is associated with a higher rate of severe cardiovascular complications as compared with patients in whom aspirin and clopidogrel / Prasugrel is maintained during the subsequent 6 months of follow-up.