December 28, 2012Open Access
Clopidogrel Hyper-Response and Bleeding Risk in Neurointerventional Procedures
Resultado clave
Clopidogrel hyper-response was associated with increased risk of hemorrhagic complications, with median platelet inhibition of 94% in major bleeding vs 24% in minor/no bleeding (P=0.0084).
Diseño del estudio
Tipo
Observational (n=47)
PICO estructurado
Does clopidogrel hyper-response increase the risk of hemorrhagic complications in patients undergoing neurointerventional procedures?
P
Población
47 patients (mean age 56, 72% female) treated with antiplatelet medications undergoing neurointerventional procedures.
E
Exposición
Clopidogrel hyper-response (defined as ≥72% platelet inhibition measured by VerifyNow assay)
C
Comparador
Normal or low response to clopidogrel (<72% platelet inhibition)
O
Resultado
Postprocedural major and minor hemorrhagic complicationssafety
Resultado numérico
valor p: p=0.0084
Limitaciones
- Small sample size requiring larger studies to validate a clinically useful threshold for hyper-response
Resumen
BACKGROUND AND PURPOSE: Antiplatelet therapy is associated with decreased ischemic events after neurointerventional procedures. Antiplatelet resistance negates the protective effects of antiplatelet medication, leading to a higher incidence of ischemic events. A possible link between antiplatelet hyper-response and increased hemorrhagic complications has been inadequately investigated. We aimed to examine the correlation between antiplatelet hyper-response and the risk of hemorrhagic complications. MATERIALS AND METHODS: Patients who were treated with antiplatelet medications and underwent neurointerventional procedures were prospectively recruited. We collected the following data: demographics, vascular risk factors, antiplatelet and anticoagulation treatment, antiplatelet responsiveness, coagulation profile, and hemorrhagic complications. P2Y12 receptor-mediated platelet inhibition was tested by using the VerifyNow assay device. The primary end points were postprocedural major and minor hemorrhagic complications. Receiver operator characteristic analysis was used to evaluate the percentage of platelet inhibition as a diagnostic tool for bleeding events. The association between hemorrhage and percentage of platelet inhibition was investigated by using logistic regression modeling. RESULTS: Forty-seven patients were enrolled. The mean age was 56±12 years, and 28% were men. Ten patients (21.3%) developed hemorrhagic complications. Clopidogrel response was higher in patients with a major bleeding complication compared with those with minor or no bleeding (median, 94% versus 24% platelet inhibition; P=.0084). Of the 7 patients (14.9%) defined as hyper-responders with ≥72% platelet inhibition, 42.8% had a major bleeding complication. CONCLUSIONS: Hyper-response to clopidogrel is associated with increased risk of hemorrhagic complications. Larger studies are urgently needed to validate a clinically useful threshold to define clopidogrel hyper-response and to examine the clinical effects of antiplatelet dosage adjustment.