Clinical Impact of P2Y12 Pretreatment in ST-Segment Elevation Myocardial Infarction: Insights from the SEMPRE (St-Elevation Mestre Pretreatment Registry) Study.

Early administration of P2Y12 receptor antagonists, in patients admitted with ST-segment elevation myocardial infarction (STEMI) diagnosis, is still debatable. Aim of this observational registry was to describe the clinical impact of a preloading strategy on coronary reperfusion and in-hospital bleeding in a real-world population, compared with patients who did not receive a P2Y12 receptor antagonist. Consecutive patients from January 2016 to April 2021 with STEMI, who underwent emerging coronary angiography in our institution were included. Primary outcomes were: infarct related artery (IRA) patency; definite or probable stent thrombosis (ST) and in-hospital BARC3-5 bleeding. To overcome the limit of the observational nature of the study an inverse-probability-weighting (IPW) analysis has been performed to adjust for baseline differences. A total of 1004 patients were included, 70% of them did not receive a P2Y12 inhibitor, while 301 patients (30%) were pretreated with a P2Y12 inhibitor before coronary angiography. We have not found differences in IRA reperfusion (46.9% vs. 46.8%; p = 0.81), final TIMI 3 flow after PCI (85.6% vs. 84.9%; p = 0.47) and acute or subacute ST (2% vs. 0.7%; p = 0.17). BARC 3-5 bleeding was significantly higher in the P2Y12 inhibitor-pretreated group (7.3% vs. 3.3%; p = 0.005). At multivariate analysis, pretreatment with a P2Y12 inhibitor, before knowing the coronary anatomy, was an independent predictor of hemorrhagic events (adj OR 3.45 [95% CI 1.78 to 6.69]; p <0.001), In STEMI patients, a routine pretreatment strategy with a P2Y12 inhibitor, before the coronary angiography, seems to not impact on reperfusion outcomes, despite a trend toward increased risk of stent thrombosis; on the other hand, it may increase the risk of major bleedings.