Reduction of in-stent thrombus immediately after percutaneous coronary intervention by pretreatment with prasugrel compared with clopidogrel: An optical coherence tomography study

Background: Prasugrel is a new-generation thienopyridine antiplatelet agent that provides more consistent and prompt platelet inhibition than clopidogrel. The aim of this study was to compare in-stent thrombus inhibition effect of pretreatment with prasugrel and clopidogrel by using optical coherence tomography (OCT) immediately after percutaneous coronary intervention (PCI) for acute coronary syndrome (ACS). Methods: We performed OCT immediately after PCI in 108 ACS patients pretreated with either prasugrel (n = 51) or clopidogrel (n = 57). OCT detected thrombus/plaque protrusion in all stented segments. Results: Although stent volume (190.4 +/- 119.1 mm(3) vs. 189.4 +/- 95.8 mm(3), p = 0.961), mean stent area (6.9 +/- 2.9 mm(2) vs. 7.1 +/- 2.0 mm(2), p = 0.772), and minimum stent area (5.6 +/- 2.7 mm(2) vs. 5.4 +/- 1.7 mm(2), p = 0.554) were not different between the two groups, in-stent thrombus/plaque protrusion volume (1.8 +/- 2.9 mm(3) vs. 4.5 +/- 5.3 mm(3), p = 0.002), mean in-stent thrombus/plaque protrusion area (0.1 +/- 0.1 mm(2) vs. 0.2 +/- 0.2 mm(2), p = 0.005), and maximum in-stent thrombus/plaque protrusion area (0.5 +/- 0.7 mm(2) vs. 0.8 +/- 0.6 mm(2), p = 0.007) were significantly smaller in the prasugrel group compared with the clopidogrel group. Conclusions: Pretreatment with prasugrel was associated with significantly reduced in-stent thrombus/ plaque protrusion immediately after PCI for ACS compared with that with clopidogrel. (C) 2016 Japanese College of Cardiology. Published by Elsevier Ltd. All rights reserved.