title: Differential effect of ticagrelor versus prasugrel on coronary blood flow velocity in patients with non-ST-elevation acute coronary syndrome undergoing percutaneous coronary intervention: an exploratory study.
abstract: BACKGROUND
  Prasugrel and ticagrelor provide a superior anti-ischemic action than clopidogrel, with some of ticagrelor's benefits possibly attributed to adenosine-mediated mechanisms. We aimed to compare the effect of maintenance dose of ticagrelor versus prasugrel on coronary blood flow velocity (CBFV) during increasing doses of intravenously administered adenosine.
  
  
  RESULTS
  In a prospective, single-center, single-blind, crossover study, 56 patients with non-ST-elevation acute coronary syndrome undergoing percutaneous coronary intervention were randomized to receive either ticagrelor 90 mg BID or prasugrel 10 mg OD with a 15-day treatment period. At the end of each treatment period, CBFV by transthoracic Doppler echocardiography was assessed at baseline and under incremental doses (50 μg/kg per minute, 80 μg/kg per minute, 110 μg/kg per minute, and 140 μg/kg per minute) of adenosine infusion. Maximal CBFV area under the curve was higher for ticagrelor-treated than for prasugrel-treated patients, with a least squares mean difference of 7.16 (95% confidence interval, 2.61-11.7; P=0.003). Maximal CBFV/baseline CBFV ratio was higher with ticagrelor than prasugrel at 50, 80, and 110 μg/kg per minute but not at 140 μg/kg per minute adenosine infusion rate, with mean difference (95% confidence interval) of 0.17 (0.08-0.26; P<0.001), 0.21 (0.02-0.41; P=0.03), 0.24 (0.01-0.47; P=0.04), and 0.14 (-0.12 to 0.4; P=0.3), respectively.
  
  
  CONCLUSIONS
  In patients with non-ST-elevation acute coronary syndrome undergoing percutaneous coronary intervention, ticagrelor augments CBFV to a greater extent than prasugrel when incremental doses of adenosine are administered. Although exploratory, these results may represent a pleiotropic action of ticagrelor, possibly contributing to its beneficial effects in such patients.
authors.affiliation: Department of Cardiology, Patras University Hospital, Rion, Patras, Greece. dalex@med.upatras.gr
authors.forename: Dimitrios
authors.initials: D
authors.lastname: Alexopoulos
authors.forename: Athanasios
authors.initials: A
authors.lastname: Moulias
authors.forename: Nikolaos
authors.initials: N
authors.lastname: Koutsogiannis
authors.forename: Ioanna
authors.initials: I
authors.lastname: Xanthopoulou
authors.forename: Apostolos
authors.initials: A
authors.lastname: Kakkavas
authors.forename: Eleni
authors.initials: E
authors.lastname: Mavronasiou
authors.forename: Periklis
authors.initials: P
authors.lastname: Davlouros
authors.forename: George
authors.initials: G
authors.lastname: Hahalis
mesh_terms: D054058:Acute Coronary Syndrome / Q000175:diagnosis / Q000503:physiopathology / Q000628:therapy*; D000241:Adenosine / Q000008:administration & dosage / Q000031:analogs & derivatives* / Q000627:therapeutic use; D061605:Administration, Intravenous; D000368:Aged; D019540:Area Under Curve; D001783:Blood Flow Velocity / Q000187:drug effects; D003326:Coronary Circulation / Q000187:drug effects*; D018592:Cross-Over Studies; D015150:Echocardiography, Doppler; D005260:Female; D006115:Greece; D006801:Humans; D016018:Least-Squares Analysis; D008297:Male; D008875:Middle Aged; D062645:Percutaneous Coronary Intervention; D010879:Piperazines / Q000627:therapeutic use*; D010975:Platelet Aggregation Inhibitors / Q000627:therapeutic use*; D000068799:Prasugrel Hydrochloride; D011237:Predictive Value of Tests; D011446:Prospective Studies; D016037:Single-Blind Method; D013876:Thiophenes / Q000627:therapeutic use*; D000077486:Ticagrelor; D016896:Treatment Outcome; D014665:Vasodilator Agents / Q000008:administration & dosage
chemical_list: D010879:Piperazines; D010975:Platelet Aggregation Inhibitors; D013876:Thiophenes; D014665:Vasodilator Agents; D000068799:Prasugrel Hydrochloride; D000077486:Ticagrelor; D000241:Adenosine
keywords: P2Y12 receptor; acute coronary syndrome; adenosine; prasugrel; ticagrelor