Pretreatment With P2Y12 Inhibitors in ST-Segment Elevation Myocardial Infarction Insights From the Bern-PCI Registry

BACKGROUND Evidence to support immediate P2Y12 inhibitor loading in ST -segment elevation myocardial infarction (STEMI) is limited. OBJECTIVES This study sought to compare outcomes of STEMI patients receiving immediate or delayed P2Y12 inhibitor treatment. METHODS Using data from the prospective Bern-PCI registry between 2016 and 2020, we stratified STEMI patients undergoing percutaneous coronary intervention according to time periods with different institutional recommendations regarding P2Y12 inhibitor pretreatment. In cohort 1 (October 2016 -September 2018), immediate P2Y12 inhibitor treatment was recommended. In cohort 2 (October 2018 -September 2020), P2Y12 inhibitor treatment was recommended after coronary anatomy was confirmed. The primary endpoint was a composite of major adverse cardiac or cerebrovascular events (MACCEs) defined as all-cause death, recurrent myocardial infarction, stroke, or definite stent thrombosis at 30 days. Sensitivity analysis included only patients in whom these recommendations were followed. RESULTS Cohort 1 included 1,116 patients; pretreatment was actually given in 708 (63.4%). Cohort 2 included 847 patients; pretreatment was withheld in 798 (94.2%). The mean age was 65 +/- 13 years, and 24% were female. Baseline characteristics were well-balanced between groups. The median difference for P2Y12 loading to angiography was 52 minutes between cohort 1 and 2 and 100 minutes between patients receiving vs not receiving pretreatment. Rates of MACCEs were similar between cohort 1 and cohort 2 (10.1% vs 8.1%; adjusted HR: 0.91; 95% CI: 0.65-1.28; P = 0.59) and between patients receiving vs not receiving pretreatment (7.1% vs 8.4%; adjusted HR: 1.17; 95% CI: 0.78-1.74; P = 0.45). CONCLUSIONS In this cohort study of patients with STEMI undergoing primary percutaneous coronary intervention, P2Y(12) inhibitor pretreatment was not associated with improved MACCEs. (J Am Coll Cardiol Intv 2024;17:17-28) (c) 2024 by the American College of Cardiology Foundation.