Myocardial Infarction with and without ST-segment Elevation: a Contemporary Reappraisal of Similarities and Differences

Understanding the similarities and differences between myocardial infarction with or without ST-segment elevation is an essential step for proper patients’ management in current practice. Both syndromes are caused by critical stenosis or total occlusion of coronary arteries (mostly due to thrombosis on atherosclerotic plaque), and manifest with a similar clinical presentation. Recent epidemiologic studies show that the relative incidence of ST-segment elevation myocardial infarction (STEMI) and non-ST-segment elevation myocardial infarction (NSTEMI) moves in an opposite fashion (decreasing and increasing respectively), with a prognosis that is worse at short-term follow-up for STEMI but comparable at long-term. Current management differs, as for STEMIs, immediate reperfusion is recommended, while for NSTEMIs, risk stratification is mandatory in order to stratify patients’ risk, and then decide the timing for coronary angiography. Periprocedural and technical aspects of the interventional management, as well as antithrombotic medications, are for the most similarly implemented in the two types of MI, with routine radial access, DES implant, and novel P2Y12 inhibitors representing the standard of care in both cases. The following review article aims to compare the two types of MI, with and without persistent ST-segment elevation. The main purpose is to explore their similarities and differences and address areas of uncertainty with regards to clinical presentation, therapeutic management, and prognosis. The identification of high-risk NSTEMI patients is important as they may require an individualised approach that can substantially overlap with current STEMI recommendations, and their mortality remains high if their management is delayed.