Overview
- The Fifth Universal Definition was published and presented at the European Society of Cardiology Congress in late August 2026, and released simultaneously in the member societies' journals.
- The document replaces the old five-number system with three clinical categories—primary, secondary, and procedure-related—to tie diagnoses to underlying causes.
- It refines myocardial injury criteria, introduces sex-specific 99th-percentile troponin reference limits to reduce under-recognition in women, and renames MINOCA as “myocardial injury with nonobstructive coronary arteries” as a working diagnosis.
- The task force worked with the World Health Organization to propose ICD-11 codes that map to the new categories and specific causes (including a code for spontaneous coronary artery dissection), while surgical and interventional societies have issued endorsements.
- Authors say the changes aim to cut the misclassification seen under the old system—previous adjudication found large rates of reclassification for type 1 and type 2 MIs—improve patient communication, tailor treatment by cause, and allow large-scale study of under-recognized mechanisms, though adoption will require coding updates and clinician education.