Clopidogrel Gene Mutation Linked to Higher Rate of Stent Thrombosis

February 13, 2009 (Munich, Germany) — A polymorphism in one of the genes responsible for metabolizing clopidogrel to its active form has been shown to be associated with an increased risk of stent thrombosis in patients undergoing PCI.

The study, published online February 4, 2009 in the European Heart Journal, was conducted by a group led by Dr Dirk Sibbing (Deutsches Herzzentrum, Munich, Germany).

The mutant *2 allele of the CYP2C19 gene occurs with a frequency of about 15%. In the current study, 25% of patients had one copy of the genotype (ie, were heterozygous) and 2% of the group were homozygous. Patients who were heterozygous had an increased risk of stent thrombosis compared with those without this genotype, and those who were homozygous had a higher risk again.

"The results of the present study identify patients at high risk for stent thrombosis and provide a rationale for administration of an intensified antiplatelet treatment in patients scheduled for coronary stent placement. Genetic determination of the CYP2C19 loss-of-function polymorphism may be beneficial in this setting, as high-risk patients can be identified prior to the planned procedure. High clopidogrel maintenance dosing or the use of novel and more potent P2Y12-receptor antagonists, such as prasugrel, may be potential treatment options for tailored antiplatelet therapy in CYP2C19*2 carriers"