Acute Carotid Stent Thrombosis in an Ultrarapid Clopidogrel Metabolizer: Case Report and Literature Review

Introduction: Carotid angioplasty and stenting (CAS) represents an effective procedure for treating carotid artery disease. The acute in-stent thrombosis is an extremely rare complication of CAS especially when it occurs postprocedurally during the first 24 hours. Improper antiplatelet therapy or poor response to antiplatelet medications is known to be associated with a higher risk of in-stent thrombosis during early postprocedural period following a successful intervention. Material and Methods: A patient who experienced acute carotid in-stent thrombosis in early postprocedural period is described. He had been taking dual antiplatelet therapy for 2 weeks before undergoing a successful CAS. Moreover, pharmacogenetics studies showed the patient to be a clopidogrel ultrarapid metabolizer, which theoretically confers hyperresponsivity to medication. Alongside the report itself, a brief literature review of relevant sources pertinent to the case has been conducted. Results: According to the available literature, this is the first case report describing an ultrarapid clopidogrel metabolizer who underwent an uneventful CAS but experienced acute carotid in-stent thrombosis in early postprocedural period. A rescue procedure included an endovascular intervention consisting of thrombectomy and local alteplase application, followed by postprocedural administration of intravenous eptifibatide. At discharge, patient's dual antiplatelet therapy included ticagrelor instead of clopidogrel. Conclusion: Acute carotid in-stent thrombosis is a highly unexpected complication of CAS and can occur despite ultrarapid clopidogrel metabolism trait.