To access, purchase, authenticate, or subscribe to the full-text of this article, please visit this link: http://dx.doi.org/10.1016/j.ahj.2017.07.013 Byline: Payam Dehghani, MD [email@example.com] (a,*), Andrea Lavoie, MD (a), Shahar Lavi, MD (b), Jennifer J. Crawford, PhD (a), Sebastian Harenberg, PhD (a), Rodney H. Zimmermann, MD (a), Jeff Booker, MD (a), Sheila Kelly, MSc (a), Warren J. Cantor, MD (c), Shamir R. Mehta, MD (d), Akshay Bagai, MD (e), Shaun G. Goodman, MD, MSc (e), Asim N. Cheema, MD, PhD (e) Objectives Patients undergoing PCI early after fibrinolytic therapy are at high risk for both thrombotic and bleeding complications. We sought to assess the pharmacodynamic effects of ticagrelor versus clopidogrel in the fibrinolytic-treated STEMI patients undergoing early PCI. Methods and results Patients undergoing PCI within 24 hours of tenecteplase (TNK), aspirin, and clopidogrel for STEMI were randomized to receive additional clopidogrel 300 mg followed by 75 mg daily or ticagrelor 180 mg followed by 90 mg twice daily. The platelet reactivity units (PRU) were measured with the VerifyNow Assay before study drug administration (baseline) at 4 and 24 hours post-PCI. The primary end point was PRU [less than or equal to]208 at 4 hours. A total of 140 patients (74 in ticagrelor and 66 in clopidogrel group) were enrolled. The mean PRU values at baseline were similar for the 2 groups (257.8 [plus or minus] 52.9 vs 259.5 [plus or minus] 56.7, P= .85, respectively). Post-PCI, patients on ticagrelor, compared to those on clopidogrel, had significantly lower PRU at 4 hours (78.7 [plus or minus] 88 vs 193.6 [plus or minus] 86.5, respectively, P Conclusion Fibrinolysis-treated STEMI patients who received clopidogrel and aspirin at the time of fibrinolysis and were undergoing early PCI frequently had PRU 208. In this high-risk population, ticagrelor provides more prompt and potent platelet inhibition compared with clopidogrel (Funded by Astra Zeneca; NCT01930591, https://clinicaltrials.gov/ct2/show/NCT01930591). Author Affiliation: (a) Prairie Vascular Research Network and Regina Qu'Appelle Health Region, University of Saskatchewan, Regina, Saskatchewan, Canada (b) London Health Sciences, University of London, London, Ontario, Canada (c) Southlake Regional Health Centre, University of Toronto, Newmarket, Ontario, Canada (d) Hamilton Health Sciences, McMaster University, Hamilton, Ontario, Canada (e) Terrence Donnelly Heart Centre, St. Michael's Hospital, University of Toronto, Toronto, Ontario, Canada * Reprint requests: Payam Dehghani, MD, Regina Qu'Appelle Health Region, Regina General Hospital Unit 3A(CCU), Interventional Cardiology Research Office, 1440-14th Ave, Regina, Saskatchewan S4P 0W5, Canada. Article History: Received 5 April 2017; Accepted 12 July 2017 (footnote) RCT# NCT01930591.