The Fifth Universal Definition of Myocardial Infarction (2026): A new revolution for our practice?

“There's one other really important update to this definition, and that is the introduction of sex-specific cardiac troponin thresholds. This is important to avoid sex bias in care, and to ensure that we don't underrecognize both myocardial infarction and other important structural heart conditions, which are often only identified by the presence of myocardial injury in women because women consistently have lower troponin values than men.”

“Previously, MINOCA referred to myocardial infarction with non-obstructive coronaries, and the new document changed that definition to myocardial injury with non-obstructive coronary artery. Let me explain in simple words why that matters. Imagine a woman comes to the hospital with chest pain, and her blood test shows that she has some kind of injury to the heart muscle, but when they look at the coronary arteries, they don't find any major blockage. Further testing, such as a cardiac MRI, can help determine whether she had a heart attack or another cause of heart injury, such as inflammation of the heart muscle. So that change from heart attack to heart injury reinforces that MINOCA is a working diagnosis, not a final diagnosis. Finding no major blockage does not mean the evaluation is finished.”

“[Heart attack] is now defined as one of three classifications — primary, secondary, procedure-related — that reflect the underlying pathology and align with clinical care, making it easier to apply in practice and allowing more precise treatment based on the underlying cause.”