BACKGROUND: Bivalirudin was not superior to unfractionated heparin in patients with myocardial infarction (MI) treated with percutaneous coronary intervention and no planned use of GPI (glycoprotein IIb/ IIIa inhibitors) in contemporary clinical practice of radial access and potent P2Y(12)-inhibitors in the VALIDATE- SWEDEHEART randomized clinical trial (Bivalirudin Versus Heparin in STEMI and NSTEMI Patients on Modern Antiplatelet Therapy-Swedish Web-System for Enhancement and Development of Evidence-Based Care in Heart Disease Evaluated According to Recommended Therapies Registry). METHODS: In this prespecified separately powered subgroup analysis, we included patients with ST-segment-elevation MI undergoing primary percutaneous coronary intervention with the primary composite end point of all-cause death, MI, or major bleeding event within 180 days. RESULTS: Among the 6006 patients enrolled in the trial, 3005 patients with ST-segment-elevation MI were randomized to receive bivalirudin or heparin. The mean age was 66.8 years. According to protocol recommendations, 87% were treated with potent oral P2Y(12)-inhibitors before start of angiography and radial access was used in 90%. GPI was used in 51 (3.4%) and 74 (4.9%) of patients randomized to receive bivalirudin and heparin, respectively. The primary end point occurred in 12.5% (187 of 1501) and 13.0% (196 of 1504; hazard ratio [HR], 0.95 [95% CI, 0.78-1.17], P=0.64) with consistent results in all major subgroups. All-cause death occurred in 3.9% versus 3.9% (HR, 1.00 [0.70-1.45], P=0.98), MI in 1.7% versus 2.2% (HR, 0.76 [0.45-1.28], P=0.30), major bleeding in 8.3% versus 8.0% (HR, 1.04 [0.81-1.33], P=0.78), and definite stent thrombosis in 0.5% versus 1.3% (HR, 0.42 [0.18-0.96], P=0.04). CONCLUSIONS: In patients with ST-segment-elevation MI undergoing primary percutaneous coronary intervention with radial access and receiving current recommended treatments with potent P2Y(12)-inhibitors rate of the composite of all-cause death, MI, or major bleeding was not lower in those randomized to receive bivalirudin as compared with heparin.