Introduction: The National Cardiovascular Data Registry affords a 10-year perspective of the landscape of STEMI patient characteristics, management, and clinical outcomes.Methods: Annual trends in patient characteristics and in-hospital treatments of 604,936 STEMI patients treated at 1226 US hospitals between 2009 and 2018 were analyzed. Using the ACTION mortality risk model incorporating cardiac arrest, the trend in in-hospitals risk adjusted mortality rates (RAMR) between 2011-2018 was tested.Results: While patient age (median 61 years) and sex (70.7% male) remained stable over time, the prevalence of diabetes (22.8% in 2009 to 28.3% in 2018) and atrial fibrillation (4.1% to 6.1%) increased, while smoking decreased (43.5% to 37.9%) . Among eligible patients, primary PCI use increased (82.3% to 96.0%) with more rapid door to balloon times for both direct arrival (median 62 min vs 56 min) and transferred-in pts (median 113 min vs 103 min, p for trend <0.001 for all). Thrombolytic use declined (10.1% to 5.0%) with no significant change in door to needle time (median 27 minutes). There was no significant change in RAMR (2.83% to 2.69%, p=0.46) from 2011-2018. (Figure 1). Discharge use of P2Y12 inhibitors (91.5% to 95.6%) and statins (94.9% to 98.5%) increased.Conclusions: Characteristics of patients presenting with STEMI changed over time with improvements in primary PCI use and timeliness. However, there was no significant reduction in risk-adjusted mortality over the past decade.