Late stent thrombosis in a patient with CYP2C19*3/*17 genotype and clopidogrel high on-treatment platelet reactivity

Abstract

Aim: Recurrent thrombotic events still occur despite dual antiplatelet therapy in patient's post percutaneous coronary intervention (PCI) could be attributed to high on-treatment platelet reactivity. Methods: A 44-year-old male, who had staged PCI to left anterior descending (LAD) 2 weeks after an anterior MI, with a drug-coated stent was readmitted with new anterior STEMI 35 days later. Coronary angiogram revealed mid-stent thrombus in situ. He had further uncomplicated PCI. Platelet function testing and genotyping showed clopidogrel high on-treatment platelet reactivity and CYP2C19*3/*17 genotype. Ticagrelor was commenced. Results & conclusion: This case study is the first reported in Malaysia to document a patient with a CYP2C19*3/*17 genotype presenting with a stent thrombosis after an uncomplicated index PCI procedure.