Safety and efficacy of aspirin, clopidogrel, and warfarin after coronary stent placement in patients with an indication for anticoagulation.

Background: Dual antiplatelet therapy with aspirin and clopidogrel has replaced aspirin and systemic anticoagulation with warfarin as the preferred antithrombotic therapy after percutaneous coronary intervention (PCI) with stent placement. However, a number of patients have indications for all 3 drugs. We sought to determine the frequency and type of hemorrhagic complications in patients who undergo systemic anticoagulation with warfarin while receiving aspirin and clopidogrel after a PCI with stent placement.
Methods: We performed a retrospective analysis of the Mayo Clinic PCI database and identified 66 consecutive patients who were discharged from hospital after PCI between January 2000 and August 2002 (inclusive) receiving a combination of dual antiplatelet therapy (aspirin and clopidogrel) and systemic anticoagulation (warfarin) to determine the incidence of bleeding and other clinical events during the treatment period.
Results: Six patients (9.2%; 95% CI, 3.5-19.0) reported a bleeding event; 2 patients required a blood transfusion. No patient died or sustained a myocardial infarction or stent thrombosis.
Conclusions: The risk of bleeding may be increased in patients treated with aspirin, a thienopyridine, and warfarin early after PCI with stent placement.