BACKGROUND Clopidogrel, in addition to aspirin, has become a common treatment of acute coronary syndrome and for stent thrombosis prevention, when given before percutaneous transluminal coronary angioplasty. However, some patients turn out to have surgical coronary artery disease and are sent for coronary artery bypass grafting (CABG) where the irreversible effect of aspirin and clopidogrel on ...

BACKGROUND Utilization of the irreversible antiplatelet agent clopidogrel is increasing in the treatment acute coronary syndrome patients. Consequently, more patients are presenting for urgent cardiac surgery with an irreversible defect in platelet function. The objective of this study was to determine whether recent clopidogrel administration predicts transfusion and hemorrhagic complication i...

Antiplatelet agents are mainly used in the prevention and management of atherothrombotic complications. Dual antiplatelet therapy, combining aspirin and clopidogrel, is the standard care for patients having acute coronary syndromes or undergoing percutaneous coronary intervention according to the current ACC/AHA and ESC guidelines. But in spite of administration of dual antiplatelet therapy, so...

OBJECTIVE Platelet dysfunction is a common cause of bleeding after coronary artery bypass graft (CAG) surgery. This prospective observational audit explored the effects of clopidogrel and aspirin on chest drain output for the first 24 hours after CAG surgery. METHODS During a 7 week period from July to Aug 2003, all patients who underwent CAG at the London Chest Hospital were audited. Patient...

UNLABELLED Acute coronary syndrome (ACS) guidelines recommend that most patients receive dual antiplatelet therapy with clopidogrel and acetylsalicylic acid (ASA) at the time of presentation to prevent recurrent ischemic events. Approximately 10% of ACS patients require coronary artery bypass grafting surgery (CABG) during the index admission. Most studies show that patients who receive ASA and...

Dual antiplatelet therapy with aspirin plus thienopyridines has become the standard treatment of patients undergoing coronary stenting. Clopidogrel has mostly replaced the use of ticlopidine due to its more favourable adverse event profile. However, also the use of clopidogrel is not without side effects. Clopidogrel major adverse events are represented by marrow suppression, manifesting with a...

BACKGROUND The degree of antiplatelet response to clopidogrel has been associated with clinical outcomes. Studies have investigated whether adjustment of antiplatelet therapies based on a single platelet function test is beneficial. OBJECTIVES The aim of the study was to test the stability of platelet reactivity measurements over time among patients treated with standard and double doses of c...

BACKGROUND The increasing use of higher-than-approved doses of clopidogrel in clinical practice is based in part on the desire for greater levels of inhibition of platelet aggregation (IPA). Prasugrel is a new thienopyridine that is more potent than standard-dose clopidogrel in healthy subjects and patients with stable coronary artery disease. The relative antiplatelet effects of prasugrel vers...

OBJECTIVE Metabolic activity of cytochrome P450 (CYP) 3A4 has been associated with clopidogrel response variability. Because metabolic activity of CYP3A4 is genetically regulated, we hypothesized that genetic variations of this enzyme may contribute to clopidogrel response variability. METHODS AND RESULTS The CYP3A4*1B, CYP3A4*3, IVS7+258A>G, IVS7+894C>T, and IVS10+12G>A polymorphisms of the ...

BACKGROUND Clopidogrel is a potent drug for prevention of adverse effects during and after coronary intervention. Increasing experience indicates that a significant proportion of patients do not respond adequately to clopidogrel. Because failure of antiplatelet therapy can have severe consequences, there is need for a reliable assay to quantify the effectiveness of clopidogrel treatment. METH...