Pretreatment with P2Y12 Receptor Antagonists in ST-Elevation Myocardial Infarction: A Report from the Swedish Coronary Angiography and Angioplasty Registry

Aims Pretreatment of patients with ST-elevation myocardial infarction (STEMI) with P2Y(12) receptor antagonists is supported by guidelines and is a common practice despite the lack of definite evidence for its benefit. Methods and results Using data from the Swedish Coronary Angiography and Angioplasty Registry on procedures between 2005 and 2016, we stratified all patients who underwent primary percutaneous coronary intervention due to STEMI in Sweden by whether or not they were pretreated with P2Y(12) receptor antagonists. We investigated associations between pretreatment with P2Y(12) receptor antagonists and the risk of adverse outcomes using propensity score-adjusted mixed-effects logistic regression, which accounted for clustering of patients within hospitals. The primary endpoint was all-cause death within 30 days. Secondary endpoints were infarct-related artery (IRA) occlusion, 30-day stent thrombosis, in-hospital bleeding, neurological complications, and cardiogenic shock. In total, 44 804 patients were included. They were treated with clopidogrel (N=26 136, 58.3%), ticagrelor (N=15 792, 35.3%), or prasugrel (N=2352, 5.3%); 37 840 (84.5%) were pretreated, and 30 387 (67.8%) had IRA occlusion. At 30 days, there were 2488 (5.6%) deaths and 267 (0.6%) stent thrombosis. Pretreatment was not associated with better survival at 30 days [odds ratio (OR) 1.08, 95% confidence interval (CI) 0.95-1.24; P = 0.313], reduced IRA occlusion (OR 0.98, 95% CI 0.92-1.05; P = 0.608), decreased stent thrombosis (OR 0.99, 95% CI 0.69-1.43; P = 0.932), higher risk of in-hospital bleeding (OR 1.05, 95% CI 0.89-1.26; P = 0.526), or neurological complications (OR 0.72, 95% CI 0.43-1.21; P = 0.210). Conclusion Pretreatment of STEMI patients with P2Y(12) receptor antagonists was not associated with improved clinical outcomes.