Serial monitoring of P2Y12 levels after ischemic stroke: Preliminary Report

초록

Purpose : Clopidogrel is one of popular medication in patients after acute ischemic stroke. Platelet function test can predict the stroke recurrence in the stroke patients taking antiplatelet agents. Timedependent changes in platelet reactivity have been reported in patients with coronary artery disease. However, it remained unclear which time is proper for checking platelet reactivity after acute stroke.Therefore, we sought to evaluate the timedependent changes in platelet reactivity to clopidogrel in the acute stage and 3 months after ischemic stroke onset. Methods : We conducted a single hospital based, prospective, observational study. P2Y12 reaction units (PRUs), was measured by VerifyNow assay serially(within 7 days and 3 months after stroke onset). PRU ≤ 240 was used as cutoff to identify clopidogrel responder and clopidogrel nonresponder. We analyzed the change of clopidogrel reactivity between acute stage and chronic stage. Results : Both the acute and the followup PRUs were measured in 75 patients in this study. In acute stroke period, 39 patients(52%) were nonresponders to clopidogrel. Among nonresponders in acute stage, 20 patients(51%) changed to responders in 3 months after stroke onset. However, among 36 responders in acute stage, 15 subjects(41%) changed to nonresponders. Conclusions : Our results suggested that clopidogrel reactivities changed over acute stroke period in many patients. Further studies are needed to investigate the usefullness of serial platelet reactivity assays and to find the proper time for platelet function test.