🫀Types 1, 2, 3, 4 and 5 myocardial infarction as we knew them are gone. Perhaps the most important conceptual change presented this morning at #ESCCongress comes from the Fifth Universal Definition of Myocardial Infarction. The new classification moves away from numbers and toward pathophysiology. We now have three clinical categories: Primary MI now includes the complete spectrum of acute primary coronary pathology, not only atherothrombosis. Plaque rupture or erosion, spontaneous coronary artery dissection, coronary embolism and coronary vasospasm all belong here. Even restenosis, stent thrombosis or graft failure occurring more than 30 days after a procedure are considered new primary coronary disease rather than late procedural MI. This fundamentally cleans up one of the problems of the old Type 2 classification. And Type 2 MI? The concept becomes secondary myocardial infarction, but importantly with greater diagnostic specificity. An ICU patient with sepsis, anaemia, hypoxaemia, hypotension, tachyarrhythmia or severe hypertension may have a rise and fall in troponin. That establishes acute myocardial injury. It does not automatically establish myocardial infarction. For secondary MI, the injury must occur in the context of oxygen supply–demand imbalance with evidence supporting myocardial ischaemia, and the new document places much greater emphasis on objective coronary or cardiac imaging when appropriate. For those of us working with critically ill patients, this distinction matters enormously. Troponin is a marker of myocardial injury. Ischaemia makes it myocardial infarction. The mechanism tells us which infarction we are dealing with. There are other major changes. Type 3 MI disappears. Sudden cardiac death suspected to be due to MI should instead be classified as primary, secondary or procedure-related according to the clinical setting or post-mortem findings. Types 4 and 5 disappear as separate entities. PCI- and surgery-related events are unified under procedure-related MI, applying a common mechanistic framework to cardiac procedures. And importantly, the old arbitrary troponin thresholds of 5× and 10× the 99th percentile are no longer the basis for defining PCI- and CABG-related MI. The emphasis shifts toward demonstrating a clinically meaningful procedural coronary complication and myocardial consequences. Another fascinating change: MINOCA no longer means “myocardial infarction with non-obstructive coronary arteries”..It is now “myocardial injury with non-obstructive coronary arteries.” A deliberate reminder that MINOCA is a working diagnosis, not an aetiological endpoint. @European Society of Cardiology @escardio #ESCCongress #MyocardialInfarction #Troponin #ACS #CriticalCare #Cardiology @escardio @ACCinTouch @American_Heart @worldheartfed @ehj_ed @KralerSimon @drmilicaa