Impact of P2Y12 inhibitor pretreatment on angiographic findings and clinical outcomes in patients with ST-elevation myocardial infarction

The optimal timing of P2Y12 inhibitor administration remains a subject of debate. While P2Y12 pretreatment may enhance early platelet inhibition, its impact on thrombus burden (TB) in patients with ST-elevation myocardial infarction (STEMI) undergoing percutaneous coronary intervention (PCI) remains unclear.

This study aims to assess the impact of P2Y12 inhibitor pretreatment compared to cath-lab treatment on angiographic and clinical outcomes in STEMI patients undergoing PCI.

We prospectively enrolled STEMI patients undergoing PCI who received the P2Y12 inhibitor loading dose either at first medical contact (FMC) (pretreatment group) or after the initial angiographic assessment (cath-lab group). The primary outcome was intracoronary TB, classified as small (STB: grade 0-3) or large (LTB: grade 4-5), after guidewire crossing or small-diameter balloon inflation. Secondary outcomes included thrombolysis in myocardial infarction (TIMI) flow before and after PCI and 30-day clinical outcomes such as all-cause mortality and major adverse cardiovascular events (MACE), defined as all-cause death, myocardial infarction, stroke and heart failure hospitalization. Time-to-event analyses for clinical outcomes were performed using Kaplan–Meier estimates and compared with the log-rank test.

A total of 112 consecutive STEMI patients were included in the present analysis, with 43 patients in the pretreatment and 69 patients in the cath-lab group. The mean age was 65 ± 13 years and 77.7% of the patients were males. The median time from FMC to coronary angiography was 54 (33 – 90) minutes. There was no significant difference in the incidence of LTB in the initial angiography between the two groups (pretreatment: 60.5% versus cath-lab: 73.9%, p=0.135). Initial TIMI 0 flow, indicating no perfusion, was significantly less frequent in the pretreatment group (41.9% versus 62.3%. p=0.034). Additionally, final TIMI III flow, suggesting better reperfusion, was more frequent in the pretreatment group (97.7% versus 81.2%, p=0.01). During the 30-day follow-up, there was no significant difference in all-cause mortality between the two groups (p=0.07). However, patients in the cath-lab group experienced higher rates of MACE compared to those in the pretreatment group (p=0.02).

The findings of the present study demonstrate that pretreatment with P2Y12 at FMC in STEMI patients undergoing PCI is associated with better coronary flow before and after PCI, in addition to more favorable 30-day clinical outcomes. There was no significant difference regarding the intracoronary thrombus burden between the two strategies.

Table of baseline patient characteristic