High platelet reactivity is associated with vascular function in patients after percutaneous coronary intervention receiving clopidogrel

Background: In the present study, we evaluated the association of platelet reactivity with vascular function in patients after percutaneous coronary intervention receiving clopidogrel treatment. Methods: We enrolled 150 patients with stable CAD receiving clopidogrel regimen (75 mg/d), 1 month after percutaneous coronary intervention. Carotid-femoral pulse wave velocity (PWV) was measured as an index of aortic stiffness and augmentation index (AIx) as an index of arterial wave reflections. High on treatment platelet reactivity (HPR) was evaluated using Verify Now Assay. Verify Now reports its results in P2Y12 reaction units (PRU), and the diagnostic cutoff value is 230 PRU. Patients were evaluated prospectively up to 24 months. The primary end point was a composite of death from cardiovascular causes, nonfatal major cardiovascular events and hospitalization for cardiovascular causes. Results: There was no difference in the basic clinical and demographic characteristics between subjects with HPR and non-HPR. Subjects with high on treatment platelet reactivity and PRU > 230 had significantly increased PWV (8.81 +/- 2.25 m/s vs. 7.69 +/- 1.95 m/s, p = 0.001) and AIx (25.27 +/- 8.67% vs. 20.87 +/- 10.57%, p = 0.04) compared to subjects with PRU <= 230. PWV was also associated with PRU (r = 0.23, p = 0.02). HPR was associated with significantly increased risk of primary end point [HR = 5.38, 95% CI:(1.15, 26.04), p = 0.03]. Conclusions: Increased platelet reactivity is associated with impaired arterial stiffness in patients after percutaneous coronary intervention receiving clopidogrel treatment, highlighting another clinical factor implicated in individual platelet response to antiplatelet therapy. Moreover, increased platelet reactivity is associated with adverse outcome in these patients. (C) 2014 Elsevier Ireland Ltd. All rights reserved.