Impact of low-dose prasugrel on platelet reactivity and cardiac dysfunction in acute coronary syndrome patients requiring primary drug-eluting stent implantation: A randomized comparative study.

Objective: The aim of this study was to compare how prasugrel and clopidogrel affect platelet aggregation reactivity, cardiac enzyme release, cardiac remodeling, and the formation of in-stent thrombi after primary percutaneous coronary intervention (PCI).

Background: The advantages of using prasugrel over clopidogrel in cardiac injury following acute coronary syndrome (ACS) remain unclear.

Methods: A total of 78 ACS patients were randomly allocated into clopidogrel (300 mg loading/75 mg maintenance) or prasugrel (20 mg loading/3.75 mg maintenance) treatment groups, followed by undergoing primary PCI. Platelet reactivity and cardiac enzymes were measured before and after primary PCI. Moreover, cardiac function was measured by ultrasound echocardiography and coronary angioscopic observation was after primary PCI up to 8 months later.

Results: Antiplatelet reactivity in the prasugrel treatment group reached optimal levels (P2Y reaction units [PRU] less than 262) immediately after the administration and was maintained even at 8 months, independently of the CYP2C19 genotype. Prasugrel treatment significantly suppressed creatine kinase elevation compared to clopidogrel treatment (median value 404 IU/L to 726 IU/L vs. 189 IU/L to 1,736 IU/L, p = 0.018 for maximum values) and reduced left ventricular mass (217.2-168.8 g in prasugrel, p = 0.045; 196.9-176.4 g in clopidogrel, p = 0.061). There were no significant differences in the incidence of in-stent attached thrombi between the two groups.

Conclusions: Compared to clopidogrel, prasugrel produced a stable platelet aggregation inhibitory effect in patients with ACS regardless of CYP2C19 genotype, reduced cardiac enzyme release, and prevented cardiac remodeling after ACS.