CYP2C19 and myocardial infarction: Patients with certain CYP2C19 loss-of-function alleles (LOF), such as *2 and *3, exhibit reduced conversion of clopidogrel to its active metabolite, leading to decreased platelet inhibition and an increased risk of adverse cardiovascular events, including stent thrombosis and myocardial infarction (Simon et al., 2009; C et al., 2009).