title: Clopidogrel resistance.
abstract: Clopidogrel resistance has been used as one of the terms employed in the literature to describe different degrees of ex vivo low platelet inhibition after clopidogrel administration. In addition to the diverse nomenclature, the characterisation of clopidogrel resistance has also been problematic because different authors have given different definitions. The mechanisms responsible for this decreased platelet response are not yet clearly defined, some hypotheses have been put forward but not yet demonstrated. Although there have been no large prospective studies demonstrating that the degree of platelet inhibition is directly related to clinical outcomes, several recent studies and reports have shown an association between less platelet inhibition and more adverse events after percutaneous coronary interventions with clopidogrel therapy suggesting that clopidogrel resistance may be a marker for increased risk of recurrent cardiovascular events. Larger scale investigations are needed to support these findings.
authors.affiliation: Epworth Hospital, Richmond, Melbourne, Victoria, Australia. ernestoo@epworth.org.au
authors.forename: Ernesto
authors.initials: E
authors.lastname: Oqueli
authors.forename: Martin
authors.initials: M
authors.lastname: Hiscock
authors.forename: Ronald
authors.initials: R
authors.lastname: Dick
mesh_terms: D054058:Acute Coronary Syndrome / Q000188:drug therapy*; D000244:Adenosine Diphosphate; D000077144:Clopidogrel; D003577:Cytochrome P-450 Enzyme System / Q000187:drug effects; D004351:Drug Resistance / Q000187:drug effects*; D006801:Humans; D010974:Platelet Aggregation / Q000187:drug effects; D010975:Platelet Aggregation Inhibitors / Q000494:pharmacology* / Q000627:therapeutic use; D018048:Receptors, Purinergic P2 / Q000187:drug effects; D013988:Ticlopidine / Q000031:analogs & derivatives* / Q000494:pharmacology / Q000627:therapeutic use; D017211:Treatment Failure
chemical_list: D010975:Platelet Aggregation Inhibitors; D018048:Receptors, Purinergic P2; D000244:Adenosine Diphosphate; D003577:Cytochrome P-450 Enzyme System; D000077144:Clopidogrel; D013988:Ticlopidine