The temporal trends of ST-elevation myocardial infarction mortality according to infarct size and location: insights from the UK National MINAP registry from 2005 to 2019.

Aims: Myocardial infarction size is associated with mortality in ST-elevation myocardial infarction (STEMI). With advances in primary percutaneous coronary intervention (PPCI) and medical therapy, whether this relationship has changed over time is unclear. Methods and results: Patients with STEMI in the UK from 2005 to 2019 were included from the national AMI MINAP registry, with mortality linkage to 2021. Primary outcomes were all-cause mortality at 30 days and 1 year according to infarct size, using Cox regression models. Infarct size was stratified by Tertiles (T1-3) of peak troponin level (T1, smallest; T3, largest), across the early (2005-09), middle (2010-14), and late (2015-19) periods. Subgroup analyses assessed the relationship according to infarct location (anterior vs. non-anterior). A total of 177 214 STEMI patients were included. Adjusted 30-day mortality risk according to infarct size was highest in the early period (aHR: 1.32, 1.21-1.45, Conclusion: We observed an independent relationship between infarct size and STEMI mortality, strongest between 2005 and 2009, which reduced over time, becoming non-significant in the 2015-19 period. This association diminished more rapidly for patients with anterior STEMIs. These findings underscore the potential role of contemporary revascularization, systems of care, and guideline-directed medical therapy in reducing STEMI-related mortality.