OBJECTIVE: We aimed to identify the impact of CYP2C19 polymorphism testing on clinical outcomes in patients who have undergone carotid artery stenting (CAS).

METHODS: This was a single-center retrospective cohort study. CYP2C19 polymorphisms were identified based on the presence of two normal functional alleles in normal metabolizers (NMs), a normal functional allele and a nonfunctional allele in intermediate metabolizers and two nonfunctional alleles in poor metabolizers. Patients were recommended for the CYP2C19 polymorphism testing followed by the change in dual antithrombotic drugs (DAPT) at the discretion of the supervising physician. The primary clinical endpoint was stent thrombosis (ST). Logistic regression was used to evaluate the relative risk of clinical outcomes.

RESULTS: A total of 273 patients were included. The relative risk of ST was not reduced in patients who underwent CYP2C19 polymorphism testing than in patients without this test (3.1% vs. 3.9%, OR = 0.914, 95% CI = 0.218-3.841). The ST in NMs and non-NMs was 3.4% and 2.9%, respectively, and showing no reduction in NMs (OR = 1.145, 95% CI = 0.162-8.105). Changing DAPT did not reduce the relative risk of ST compared with non-changing (2.3% vs. 3.2%, OR = 1.604, 95% CI = 0.024-107.033).

CONCLUSIONS: CYP2C19 polymorphism was not related to stent thrombosis in patients with CAS.