Ticagrelor improves peripheral arterial function in patients with a previous acute coronary syndrome

Purpose: The novel P2Y12 antagonist ticagrelor inhibits ADP-induced platelet aggregation more potently than clopidogrel and reduces the incidence of myocardial infarction and total death in patients with an acute coronary syndrome (ACS). Besides platelet inhibitory effects, ticagrelor inhibits adenosine re-uptake and increases coronary flow reserve during adenosine infusion in man. The purpose of the present study was to determine whether ticagrelor improves peripheral arterial function in patients with a previous ACS compared to patients treated with aspirin, clopidogrel or prasugrel. Methods: 127 patients with a previous ACS (>3 months, <3 years ago) on maintenance dose of (1) no ADP-blocker, n=35, (2) clopidogrel 75 mg, n=35, (3) prasugrel 10 mg n=32, or (4) ticagrelor 90 mg, bid, n=25, were evaluated with peripheral arterial tonometry after forearm ischemia. Results: The results demonstrated that ticagrelor improves peripheral arterial function compared to the other groups: (1) 1.78±0.53 (2) 1.78±0.45 (3) 1.64±0.33 (4) 2.25±0.54, mean ± SD, ticagrelor vs no ADP-blocker p<0.01, vs clopidogrel p<0.01, vs prasugrel p<0.001. There were fewer patients with endothelial dysfunction (<1.67 RHI) in the ticagrelor group 12% compared to aspirin 51%, clopidogrel 46% and prasugrel 53%, p<0.01. Conclusion: In conclusion, our data show that, in patients with a previous ACS, treatment with ticagrelor improves peripheral endothelial function compared to no ADP-blocker, clopidogrel or prasugrel treatment. Further studies are needed to understand if this effect contributes to the clinical effects of ticagrelor.