Fifth Universal Definition of Myocardial Infarction

This international consensus document from the European Society of Cardiology (ESC), American College of Cardiology (ACC), American Heart Association (AHA), and World Heart Federation (WHF) updates myocardial infarction (MI) classification from numerical types to three clinical settings: primary, secondary, and procedure-related MI. MI requires acute myocardial injury, defined as a rise and/or fall in cardiac troponin, with at least one value above the sex specific 99th percentile, plus evidence of acute myocardial ischemia. Primary MI includes atherothrombosis, spontaneous coronary artery dissection, embolism, vasospasm, and late stent or graft failure. Secondary MI requires supply-demand imbalance with objective evidence of obstructive coronary disease or new ischemic myocardial damage. Procedure-related MI within 30 days now emphasizes coronary complications and imaging rather than fixed biomarker thresholds. The authors conclude that this classification should improve consistent diagnosis, coding, research, and patient care.