Patients with coronary stent implantation are treated with dual antiplatelet therapy with aspirin and a thienopyridine. This combination therapy reduced the rate of early stent thrombosis and allowed the widespread use of coronary stents, which are currently implanted in about 90% of patients with PCI. In patients with bare metal stents, the recommended duration of dual antiplatelet therapy is 4 weeks, while 6–12 months is recommended in patients with drug-eluting stents. However, problems arise in patients needing oral anticoagulation. Combination therapy with oral anticoagulation and antiplatelet therapy is associated with an increase in bleeding complications. So far no randomized studies have defined the optimal intensity and duration of antithrombotic therapy in these patients. Therefore the decision should be made based on an individual risk assessment for stent thrombosis and bleeding in each patient.