Eight years after its previous update, the Universal Definition of Myocardial Infarction has been revised again.
On 28 August 2026, the ESC, ACC, AHA and WHF jointly published the Fifth Universal Definition of Myocardial Infarction, replacing the fourth edition from 2018.
The most important aspect of this update is not only the revised classification, but its further clarification that:
Troponin elevation ≠ myocardial infarction.
In clinical practice, myocardial injury must first be distinguished from a true myocardial infarction, followed by identification of the underlying pathophysiological mechanism.
The new classification also moves from the previous Type 1, Type 2, Type 3, Type 4 and Type 5 system to a structure that more closely follows clinical reasoning:
Primary myocardial infarction
Secondary myocardial infarction
Procedure-related myocardial infarction
There is often a substantial time gap between cutting-edge scientific research and its genuine incorporation into clinical practice. It may take years or even decades before advances at the scientific frontier become widely adopted in clinical care.
Sources
Fifth Universal Definition of Myocardial Infarction (2026).
General information only; not a substitute for medical assessment, diagnosis or treatment.