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Medical AI Inquiry: You was designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.  Labels: BACKGROUND, RESULTS. Meshes: Adenosine Diphosphate, Aged, Aspirin, Biotransformation, Clopidogrel, Combined Modality Therapy, Coronary Artery Disease, Coronary Restenosis, Coronary Thrombosis, Drug Resistance, Drug Therapy, Combination, Epinephrine, Eptifibatide, Female, Follow-Up Studies, Humans, Male, Middle Aged, Myocardial Infarction, Peptides, Platelet Aggregation, Platelet Aggregation Inhibitors, Prodrugs, Prospective Studies, Purinergic P2 Receptor Antagonists, Recurrence, Risk, Smoking, Stents, Ticlopidine, Treatment Outcome.
user
Is clopidogrel resistance associated with increased risk of recurrent atherothrombotic events in patients with acute myocardial infarction? Context: Although clopidogrel reduces the risk of cardiovascular episodes after coronary events and stenting, a substantial number of incidents continue to occur. The antiplatelet effect of clopidogrel was studied prospectively in 60 consecutive patients who underwent primary angioplasty (percutaneous coronary intervention [PCI]) with stenting for acute ST-segment-elevation myocardial infarction (STEMI) to determine whether variability in response to clopidogrel affects clinical outcomes. Patients were stratified into 4 quartiles according to the percentage reduction of ADP-induced platelet aggregation. Although patients in the first quartile were resistant to the effects of clopidogrel (ADP-induced platelet aggregation at day 6, 103+/-8% of baseline), ADP-induced aggregation was reduced to 69+/-3%, 58+/-7%, and 33+/-12% of baseline, respectively, in patients in quartiles 2 through 4 (P<0.01 for all). In addition, epinephrine-induced platelet aggregation and platelet aggregation under flow conditions, assessed by the cone-and-plate(let) analyzer method, were reduced significantly less in the first quartile than in quartiles 2 through 4. Whereas 40% of patients in the first quartile sustained a recurrent cardiovascular event during a 6-month follow-up, only 1 patient (6.7%) in the second quartile and none in the third and fourth quartiles suffered a cardiovascular event (P=0.007).
assistant
Up to 25% of STEMI patients undergoing primary PCI with stenting are resistant to clopidogrel and therefore may be at increased risk for recurrent cardiovascular events. Final Decision: yes