Thrombogenicity and endothelial progenitor cells function during Acute myocardial infarction - comparison of Prasugrel versus Ticagrelor

Background: Thrombin generation (TG), platelet function and circulating endothelial progenitor cells (EPCs) have an important role in the pathophysiology of coronary artery disease (CAD). To date, the effect of novel P2Y 12 inhibitors on these aspects has mostly been studied in the sub-acute phase following myocardial infarction. Objectives: Comparing the effects of prasugrel and ticagrelor on TG and EPCs in the acute phase of ST-segment elevation myocardial infarction (STEMI). Methods: STEMI patients were randomized to either ticagrelor or prasugrel treatment. TG, platelet reactivity and EPCs were evaluated prior to P2Y 12 inhibitor loading dose (T0), and one day following (T1). Results: Between December 2018 - July 2021, 83 consecutive STEMI patients were randomized to ticagrelor (N = 42) or prasugrel (N = 41) treatment. No differences were observed at T0 for all measurements. P2Y 12 reactivity units (PRU) at T1 did not differ as well (prasugrel 13.2 [5.5–20.8] vs. ticagrelor 15.8 [4.0-26.3], p = 0.40). At T1, prasugrel was a significantly more potent TG inhibitor, with longer lag time to TG initiation (7.7 ± 7.5 vs. 3.9 ± 2.1 min, p < 0.01), longer time to peak (14.1 ± 12.6 vs. 8.3 ± 9.7 min, p = 0.03) and a lower endogenous thrombin potential (AUC 2186.1 ± 1123.1 vs. 3362.5 ± 2108.5 nM, p < 0.01). Furthermore, EPCs measured by percentage of cells expressing CD34 (2.6 ± 4.1 vs. 1.1 ± 1.1, p = 0.01) and CD133 (2.3 ± 1.8 vs. 1.4 ± 1.5, p = 0.01) and number of colony forming units (CFU, 2.1 ± 1.5 vs. 1.1 ± 1.0, p < 0.01) were significantly higher in the prasugrel group. Conclusion: Among STEMI patients, prasugrel as compared to ticagrelor was associated with more potent TG inhibition and improved EPCs count and function. Graphical abstract