Improved outcomes in patients with ST-elevation myocardial infarction during the last 20 years are related to implementation of evidence-based treatments: experiences from the SWEDEHEART registry 1995-2014

Aims Impact of changes of treatments on outcomes in ST-elevation myocardial infarction (STEMI) patients in real-life health care has not been documented. Methods and results All STEMI cases (n=105.674) registered in the nation-wide SWEDEHEART registry between 1995 and 2014 were included and followed for fatal and non-fatal outcomes for up to 20 years. Most changes in treatment and outcomes occurred from 1994 to 2008. Evidence-based treatments increased: reperfusion from 66.2 to 81.7%; primary percutaneous coronary intervention: 4.5 to 78.0%; dual antiplatelet therapy from 0 to 89.6%; statin: 14.1 to 93.6%; beta-blocker: 78.2 to 91.0%, and angiotensin-converting-enzyme/angiotensin-2-receptor inhibitors: 40.8 to 85.2% (P-value for-trend<0.001 for all). One-year mortality decreased from 22.1 to 14.1%. Standardized incidence ratio compared with the general population decreased from 5.54 to 3.74 (P<0.001). Cardiovascular (CV) death decreased from 20.1 to 11.1%, myocardial infarction (MI) from 11.5 to 5.8%; stroke from 2.9 to 2.1%; heart failure from 7.1 to 6.2%. After standardization for differences in demography and baseline characteristics, the change of 1-year CV-death or MI corresponded to a linear trend of 0.915 (95% confidence interval: 0.906-0.923) per 2-year period which no longer was significant, 0.997 (0.984-1.009), after adjustment for changes in treatment. The changes in treatment and outcomes were most pronounced from 1994 to 2008. Conclusion Gradual implementation of new and established evidence-based treatments in STEMI patients during the last 20 years has been associated with prolonged survival and lower risk of recurrent ischaemic events, although a plateauing is seen since around 2008.