Clopidogrel Nonresponse May Not Be a Class Effect

Findings from a crossover study suggest that most patients who do not respond to clopidogrel do respond to ticlopidine.

The platelet inhibitory response to clopidogrel varies among individuals. Compared with those who respond normally, those with decreased response are at greater risk for stent thrombosis and other adverse cardiovascular events after percutaneous coronary intervention (PCI). In a study from Italy, 143 PCI patients treated with aspirin and clopidogrel were assessed for clopidogrel nonresponse, which was defined two ways: <10% absolute decrease in maximal platelet aggregation (definition 1), and <20% decrease in percentage of maximal inhibition of platelet aggregation (definition 2). All patients were then switched to ticlopidine from clopidogrel and reassessed for ticlopidine nonresponse.

The inhibition of platelet aggregation was normally dis…

Reviewing Author

Howard C. Herrmann, MD

Disclosures

Consultant/Advisory BoardAffluent Medical; Artedrone; Caranx; Johnson & Johnson; Medtronic; Prolifagen; Wells Fargo

EquityMicrointerventional Devices, Inc.

RoyaltiesUniversity of Pennsylvania

Grant/Research SupportAbbott Vascular; Edwards Lifesciences; Johnson & Johnson; Medtronic

Editorial BoardsCatheterization and Cardiovascular Interventions; Journal of the American College of Cardiology; Circulation: Cardiovascular Interventions; JACC Cardiovascular Interventions; JACC Case Reports; JSCAI