Introduction: The risk of recurrent ischaemic events is related to platelet function, which is often assessed by thromboelastography (TEG). TEG has high interindividual variability.
Objective: To identify causal variants associated with TEG parameters in patients who receive aspirin and clopidogrel after intra- or extracranial stenting.
Methods: Patients who underwent stenting for extracranial or intracranial stenosis (70-99%) were recruited into the study. Blood samples were obtained for TEG to assess the platelet function before stenting. Aspirin- and clopidogrel-related genetic polymorphisms were determined by the MassARRAY method. Minor allele frequency and Hardy-Weinberg equilibrium (HWE) tests and linkage disequilibrium (LD) analysis were carried out. The influences of genetic polymorphism on TEG parameters were analysed by linear regression.
Results: A total of 249 patients were included in this study. Twenty-two selected single nucleotide polymorphisms (SNPs) were genotyped, and no significant deviation from HWE was found for any SNP in the study patients. Four SNPs-rs2104543, rs12772169, rs1998591 and rs1042194-within CYP2C18 were in high LD, and the genetic polymorphisms had a significant impact on the TEG parameters maximal clot strength (MAThrombin) and ADP-induced platelet-fibrin clot strength (MAADP). Patients who carried the loss-of-function CYP2C19*2 (rs4244285) allele were also at risk of increased MAThrombin and MAADP.
Conclusions: Testing for these polymorphisms may be valuable in the identification of patients at high risk of recurrent ischaemic events. Alternative treatments may be considered for these high-risk patients.
Trial registration number: NCT01925872.
Keywords: CLINICAL PHARMACOLOGY; STROKE MEDICINE.
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