Abstract 18307: Prevalence, Predictors and Prognostic Impact of High On-treatment Platelet Reactivity to Aspirin and Clopidogrel in Patients With Symptomatic Peripheral Artery Disease in Japanese Population

Abstract

Introduction: High on-treatment platelet reactivity (HPR) is associated with increased risk of ischemic events and therapeutic failure in patients with coronary artery disease, whereas its role in patients with peripheral artery disease is not widely reported. Purpose: This study aims to investigate the prevalence of HPR in patients with symptomatic peripheral artery disease and its possible predictors in Asian population. Methods: Among patients who underwent endovascular therapy at our institution during September 2013 to April 2014, 125 patients who received aspirin and/or clopidogrel were included. Residual platelet reactivity was assessed with VerifyNow aspirin and P2Y12 assays. HPR was defined as aspirin reaction units (ARU) ≧ 550 for aspirin and P2Y12 reaction units (PRU) ≧ 235 for clopidogrel. Results: The prevalence of HPR to aspirin was not significantly different between patients with intermittent claudication (IMC) and critical limb ischemia patients (22.2% and 23.2%, respectively), whereas the prevalence of HPR to clopidogrel was higher in CLI patients, especially in patients with tissue loss compared to IMC patients (39.3% and 62.5%, respectively, p<0.05). 7.7% of IMC patients and 12.5% of CLI patients showed HPR to both aspirin and clopidogrel. Multivariate analysis revealed that age and diabetes were independent predictors for HPR to clopidogrel. Conclusion: HPR to aspirin and/or clopidogrel was highly prevalent in symptomatic PAD patients in Japanese population. The prevalence of HPR was significantly higher in patients with tissue loss compared with those without. Optimizing antiplatelet regimen according to residual platelet reactivity in CLI patients would be indispensable to avoid repeat revascularization and unexpected amputation.