title: Aspirin and clopidogrel hyporesponsiveness and nonresponsiveness in patients with coronary artery stenting.
abstract: Patients undergoing coronary artery stenting receive an antiplatelet regimen to reduce the risk of antithrombotic complications. Current guidelines recommend the use of acetyl salicylic acid (aspirin) and clopidogrel as evidenced by large clinical trials. There has been a concern about variable responses of patients to aspirin and clopidogrel which may predispose them to subacute stent thrombosis or late stent thrombosis. Up to 25% of patients with acute myocardial infarction (AMI) undergoing percutaneous coronary intervention (PCI) were found to have hyporesponsiveness or resistance to clopidogrel which may predispose them to recurrent events. Dual antiplatelet regimen is a standard therapy in these patients and there is always a concern about variable responses to aspirin and clopidogrel predisposing them to acute coronary syndrome (ACS). Prevalence of this hyporesponsiveness or resistance may be due to noncompliance, genetic mutations, co-morbid situations and concomitant use of other drugs. This issue is of considerable importance in the era of coronary drug eluting stents when a long-term dual antiplatelet regimen is needed. This paper is a review for clinicians taking care of such patients with hyporesponsiveness or nonresponsiveness to dual antiplatelet regimen.
authors.affiliation: Medical Center of South Arkansas, EL Dorado, University of Arkansas for Medical Sciences, Little Rock, AR, USA. rk1965@gmail.com
authors.forename: Rakesh K
authors.initials: RK
authors.lastname: Sharma
authors.forename: Hanumanth K
authors.initials: HK
authors.lastname: Reddy
authors.forename: Vibhuti N
authors.initials: VN
authors.lastname: Singh
authors.forename: Rohit
authors.initials: R
authors.lastname: Sharma
authors.forename: Donald J
authors.initials: DJ
authors.lastname: Voelker
authors.forename: Girish
authors.initials: G
authors.lastname: Bhatt
mesh_terms: D015906:Angioplasty, Balloon, Coronary / Q000009:adverse effects / Q000295:instrumentation*; D001241:Aspirin / Q000627:therapeutic use*; D000077144:Clopidogrel; D003324:Coronary Artery Disease / Q000628:therapy*; D004351:Drug Resistance; D006801:Humans; D010975:Platelet Aggregation Inhibitors / Q000627:therapeutic use*; D010979:Platelet Function Tests; D012008:Recurrence; D018570:Risk Assessment; D012307:Risk Factors; D015607:Stents; D013927:Thrombosis / Q000209:etiology / Q000517:prevention & control*; D013988:Ticlopidine / Q000031:analogs & derivatives* / Q000627:therapeutic use; D016896:Treatment Outcome
chemical_list: D010975:Platelet Aggregation Inhibitors; D000077144:Clopidogrel; D013988:Ticlopidine; D001241:Aspirin