The HORIZONS-AMI trial evaluated the safety and efficacy of bivalirudin compared to heparin plus glycoprotein IIb/IIIa inhibitors in patients with ST-segment elevation myocardial infarction (STEMI) undergoing primary PCI. The study randomly assigned 3602 patients to receive either bivalirudin alone or heparin plus glycoprotein IIb/IIIa inhibitors. The primary endpoints were major bleeding and combined adverse clinical events (major bleeding or major adverse cardiovascular events). Bivalirudin resulted in a significantly lower 30-day rate of net adverse clinical events (9.2% vs. 12.1%; relative risk, 0.76; P=0.005) due to a lower rate of major bleeding (4.9% vs. 8.3%; relative risk, 0.60; P<0.001). Bivalirudin also reduced 30-day rates of death from cardiac causes (1.8% vs. 2.9%; relative risk, 0.62; P=0.03) and death from all causes (2.1% vs. 3.1%; relative risk, 0.66; P=0.047). The trial found that bivalirudin improved event-free survival at 30 days by significantly reducing major bleeding, with similar rates of major adverse cardiovascular events compared to heparin plus glycoprotein IIb/IIIa inhibitors.The HORIZONS-AMI trial evaluated the safety and efficacy of bivalirudin compared to heparin plus glycoprotein IIb/IIIa inhibitors in patients with ST-segment elevation myocardial infarction (STEMI) undergoing primary PCI. The study randomly assigned 3602 patients to receive either bivalirudin alone or heparin plus glycoprotein IIb/IIIa inhibitors. The primary endpoints were major bleeding and combined adverse clinical events (major bleeding or major adverse cardiovascular events). Bivalirudin resulted in a significantly lower 30-day rate of net adverse clinical events (9.2% vs. 12.1%; relative risk, 0.76; P=0.005) due to a lower rate of major bleeding (4.9% vs. 8.3%; relative risk, 0.60; P<0.001). Bivalirudin also reduced 30-day rates of death from cardiac causes (1.8% vs. 2.9%; relative risk, 0.62; P=0.03) and death from all causes (2.1% vs. 3.1%; relative risk, 0.66; P=0.047). The trial found that bivalirudin improved event-free survival at 30 days by significantly reducing major bleeding, with similar rates of major adverse cardiovascular events compared to heparin plus glycoprotein IIb/IIIa inhibitors.