Alejandro González1, Francisco Moniche2, Aurelio Cayuela3, Jose Ramón Gonzalez-Marcos2, Antonio Mayol4, Joan Montaner5. 1. Department of Radiology, Interventional Neuroradiology, Virgen del Rocio University Hospital, Seville, Spain. Electronic address: ggjandro@gmail.com. 2. Department of Neurology, Virgen del Rocio University Hospital, Seville, Spain. 3. Department of Research Unit, Virgen del Rocio University Hospital, Seville, Spain. 4. Department of Radiology, Interventional Neuroradiology, Virgen del Rocio University Hospital, Seville, Spain. 5. Neurovascular Research Group, Stroke Programme, IBIS-HVR, Seville, Spain.
Abstract
OBJECTIVE:Clopidogrel plays a central role in the treatment of patients undergoing carotid artery stenting (CAS). The objective was to evaluate the effect of clopidogrel (75 mg/d) on platelet reactivity in responders and nonresponders and the antiplatelet effect of different doses of clopidogrel in patients with high on-treatment reactivity (OTR) after CAS. METHODS:Patients with high OTR (defined by VerifyNow (Accumetrics, San Diego, Calif) assay as ≥230 P2Y12 reaction units [PRU]) were randomly assigned in a 1:1 ratio to group 1 (standard-dose clopidogrel therapy: 75 mg/d for 30 days) or group 2 (high-dose clopidogrel: 150 mg/d for 30 days). RESULTS: The study enrolled 214 patients. Of these, 115 (53.7%) were clopidogrel responders (group 0), and 99 (46.3%) had high OTR (clopidogrel nonresponders); of which, 50 were randomly assigned to group 1 and 49 to group 2. At baseline, the PRU value did not differ between group 1 (288.50 ± 46) and group 2 (295.45 ± 47.2; P = .308). Patients displayed reduced mean platelet reactivity levels at 30 days in group 1 (238.96 ± 72.25; P < .001) and group 2 (201.85 ± 77.8; P < .001). Although high-dose clopidogrel resulted in more intense platelet function inhibition, the differences between median 30-day PRU values (P = .483) and the percentage change of PRU (P = .442) for groups 1 and 2 were not significant. The incidences of transient ischemic attack, stroke, or death at up to 30 days after CAS in the high-OTR patients were similar between groups 1 and 2 (P = .481). CONCLUSIONS:Patients with high OTR undergoing CAS treated with standard-dose and double-dose clopidogrel had significantly reduced platelet reactivity after 30 days. The double dose did not result in statistically significantly greater reductions in reactivity compared with the standard dose.
RCT Entities:
OBJECTIVE:Clopidogrel plays a central role in the treatment of patients undergoing carotid artery stenting (CAS). The objective was to evaluate the effect of clopidogrel (75 mg/d) on platelet reactivity in responders and nonresponders and the antiplatelet effect of different doses of clopidogrel in patients with high on-treatment reactivity (OTR) after CAS. METHODS:Patients with high OTR (defined by VerifyNow (Accumetrics, San Diego, Calif) assay as ≥230 P2Y12 reaction units [PRU]) were randomly assigned in a 1:1 ratio to group 1 (standard-dose clopidogrel therapy: 75 mg/d for 30 days) or group 2 (high-dose clopidogrel: 150 mg/d for 30 days). RESULTS: The study enrolled 214 patients. Of these, 115 (53.7%) were clopidogrel responders (group 0), and 99 (46.3%) had high OTR (clopidogrel nonresponders); of which, 50 were randomly assigned to group 1 and 49 to group 2. At baseline, the PRU value did not differ between group 1 (288.50 ± 46) and group 2 (295.45 ± 47.2; P = .308). Patients displayed reduced mean platelet reactivity levels at 30 days in group 1 (238.96 ± 72.25; P < .001) and group 2 (201.85 ± 77.8; P < .001). Although high-dose clopidogrel resulted in more intense platelet function inhibition, the differences between median 30-day PRU values (P = .483) and the percentage change of PRU (P = .442) for groups 1 and 2 were not significant. The incidences of transient ischemic attack, stroke, or death at up to 30 days after CAS in the high-OTR patients were similar between groups 1 and 2 (P = .481). CONCLUSIONS:Patients with high OTR undergoing CAS treated with standard-dose and double-dose clopidogrel had significantly reduced platelet reactivity after 30 days. The double dose did not result in statistically significantly greater reductions in reactivity compared with the standard dose.