Ticagrelor versus clopidogrel in reducing inflammatory cell infiltration of thrombus aspirated in patients with ST-elevation myocardial infarction.

Background: Ticagrelor provides more rapid, potent, and consistent anti-platelet efficacy than clopidogrel. This randomized trial aimed to evaluate the anti-inflammation effects of ticagrelor versus clopidogrel on thrombus aspirated from the ST-elevation myocardial infarction (STEMI) patients.

Method: A total of 98 patients with STEMI and intended percutaneous coronary intervention (PCI) were randomly assigned to receive clopidogrel (600-mg loading dose) or ticagrelor (180-mg loading dose), of whom 55 with large thrombus burden underwent thrombus aspiration during PCI. Thrombus specimens were successfully aspirated from 49 patients. Finally, 24 patients in the clopidogrel group and 23 in the ticagrelor group completed the study. Inflammatory cells within thrombi were assessed by hematoxylin-eosin and immunohistochemistry stainings.

Results: Compared with the clopidogrel group, the number of total inflammatory cells per mm thrombus area in the ticagrelor group was decreased by 28% (P = 0.009). The numbers of neutrophils and myeloperoxidase-positive cells per mm thrombus area in the ticagrelor group were respectively decreased by 35% (P = 0.016) and 28% (P = 0.047), as compared with those in the clopidogrel group. Moreover, ticagrelor treatment reduced the ratio of monocytes number higher than 250 per mm thrombus area compared with clopidogrel treatment (4% versus 29%, P = 0.048).

Conclusion: In patients with undergoing PCI for STEMI, the loading dose ticagrelor regimen was associated with a reduction in inflammatory cell infiltration within thrombus compared with the loading dose clopidogrel regimen.