CYP2C19*2 genetic polymorphism and other predictors for coronary in-stent restenosis in patients on clopidogrel therapy

Abstract

Dual antiplatelet therapy (DAPT) is the cornerstone therapy in patients undergoing percutaneous coronary intervention (PCI) to prevent atherothrombotic complications. Clopidogrel with aspirin is the most commonly prescribed DAPT. Clopidogrel is a prodrug which requires hepatic activation by the cytochrome P 450 2C19 (CYP2C19) enzyme which is highly polymorphic. The loss-of- function *2 allele is the most common genetic polymorphism.CYP2C19*2 has been reported to significantly decrease the concentration of the active metabolite of clopidogrel leading to complications post-PCI, such as major adverse cardiovascular events. In-stent restenosis (ISR), defined as ≥50% re-narrowing of a deployed stent, is a complication that may threaten the long prognosis of PCI. Few studies have been conducted to explore the association between CYP2C19*2 and coronary ISR in patients receiving clopidogrel and conflicting findings have been reported.