Association of CYP2C19*2 polymorphism with clopidogrel response and 1-year major adverse cardiovascular events in a multiethnic population with drug-eluting stents.

BACKGROUND: Patients undergoing elective percutaneous coronary intervention (PCI) with drug-eluting stents (DES) who have impaired clopidogrel response, have a higher risk of subsequent major adverse cardiovascular events (MACE). AIM OF THE STUDY: To establish the relationship between CYP2C19 genotype, clopidogrel responsiveness and 1-year MACE. MATERIALS & METHODS: Aspirin/clopidogrel responses were assessed with Multiplate Analyzer and CYP2C19*2 allele by SpartanRx. RESULTS: A total of 42.0% carried ≥1 CYP2C19*2 allele. Prevalences of aspirin and clopidogrel high on-treatment platelet reactivity (HPR; local cutoffs: 300 AU*min for aspirin and 600 AU*min for clopidogrel) were 11.5% and 19.8% respectively. In multivariate ana-lysis, clopidogrel HPR was found to be an independent predictor for 1-year MACE (adj HR: 3.48, p = 0.022 ). CONCLUSION: Having clopidogrel HPR could be a potentially modifiable risk factor guided by phenotyping.