Impact of the Antithrombotic Effects of Prasugrel on Mid-Term Vascular Healing in Acute Coronary Syndrome vs. Stable Coronary Artery Disease.

Background The impact of antiplatelet drug effects on mid-term local arterial responses following percutaneous coronary intervention (PCI) remains uncertain. We evaluated the impact of the platelet reactivity of prasugrel on mid-term vascular healing between acute coronary syndrome (ACS) and stable coronary artery disease (CAD).Methods and Results:We conducted a prospective, 12-center study in 125 patients with ACS and 126 patients with stable CAD who underwent PCI with an everolimus-eluting stent (EES) and received dual antiplatelet therapy (DAPT) with prasugrel and aspirin. Serial optical coherence tomography (OCT) was performed immediately after PCI and at the 9-month follow-up to assess the association of P2Y12reaction units (PRU) with the frequency of malapposed or uncovered struts and intrastent thrombi (IST). The incidence of abnormal mid-term OCT findings did not different between the ACS and CAD arms, regardless of clinical presentation, except that uncovered struts were more frequent in the ACS than CAD arm. PRU at PCI was significantly associated with the frequency of IST at follow-up, but not with uncovered and malapposed struts. PRU at PCI was the only independent predictor of IST detected at follow-up (odds ratio 1.009). Conclusions In patients undergoing EES implantation and receiving prasugrel, achieving an adequate antiplatelet effect at the time of stent implantation may regulate thrombus formation throughout the follow-up period.