Occlusion Myocardial Infarction: A Revolution in Acutecoronary Syndrome

Overview

The 2025 ACC Guideline for the Management of Patients With Acute Coronary Syndromes claims that “Patients with NSTEMI may have a partially occluded coronary artery leading to subendocardial ischemia, while those with STEMI typically have a completely occluded vessel leading to transmural myocardial ischemia and infarction.” This is accompanied by a visual representation of a partially occlusive thrombus labeled ‘NSTEMI’ above an electrocardiogram (ECG) showing ST depression and T wave inversion, and a completely occlusive thrombus labeled ‘STEMI’ above an ECG showing ST elevation. This paradigm has remained despite two decades of angiographic and evidence-based ECG advances, which highlight the multiple reasons why a revolution in acute coronary syndrome (ACS) is needed, and has begun.

Published in: Advances in Interventional Cardiology
Published on: 19 May 2025

Background

The STEMI/NSTEMI paradigm has long guided diagnosis and management: STEMI is assumed to correspond to a fully occluded artery and warrants emergent reperfusion, while NSTEMI is considered non-occlusive.

However, angiographic data over recent decades challenge this neat separation: a substantial fraction of patients classified as NSTEMI in fact have total occlusion of a culprit coronary vessel, and these patients have worse prognoses compared to non-occlusive NSTEMIs.

The authors note a “no false negative paradox” inherent in the classic paradigm, because patients without ST elevation but with occlusion are simply labeled NSTEMI, and false negatives are hidden in classification.

To remedy this, in 2018, the “OMI Manifesto” was proposed, promoting a paradigm based on the presence or absence of acute coronary occlusion (or near-occlusion with insufficient collateral flow), regardless of whether ST elevation is present.

The authors assert that advances in ECG interpretation (including recognition of subtle signs like hyperacute T waves, ST depression in reciprocal leads, modifications in bundle branch block, etc.) and artificial intelligence make more sensitive detection of OMI feasible.

Methods

Because this is an editorial rather than an original research study, the “methods” are argumentative and literature-based rather than experimental. The authors:

Call for adoption of AI and systemic changes (e.g. registry definitions, quality metrics) to advance the OMI paradigm in real clinical care.

Review and synthesize existing angiographic and meta-analytic evidence on rates of coronary occlusion among patients without classic ST elevation.

Critique the limitations of the STEMI/NSTEMI paradigm and its entrenched influence on quality metrics and guideline approaches.

Present the concept of the OMI paradigm and survey supporting evidence, including studies where ECG reading under the OMI paradigm improved sensitivity without sacrificing specificity.

Illustrate specific ECG patterns that may portend occlusion despite the absence of ST elevation (e.g., hyperacute T waves, reciprocal changes, modified Sgarbossa criteria, etc.).

Results

Meta-analyses show that ~ 25–34 % of NSTEMI patients may harbor complete culprit artery occlusion, and that such patients have significantly worse outcomes than NSTEMI patients without occlusion.

Classic STEMI ECG criteria have limited sensitivity: pooled estimates suggest sensitivity as low as ~ 43.6 % for detecting acute coronary occlusion.

Advanced ECG interpretation under the OMI approach (including recognition of non-classic ECG patterns) has demonstrated improved sensitivity for detecting occlusion while maintaining specificity. For example, in prior studies, blinded readers using OMI criteria nearly doubled sensitivity for acute coronary occlusion compared to STEMI criteria.

The editorial also cites work showing that OMI vs. non-OMI classification better predicts mortality than STEMI vs. NSTEMI classification.

AI-based ECG models are emerging as promising tools to detect subtle ECG changes consistent with occlusion.

Conclusion

The authors conclude that the STEMI/NSTEMI paradigm is no longer sufficient and often misclassifies patients, thereby delaying or denying timely reperfusion to many true occlusions. The OMI concept reframes ACS classification around pathophysiology (occlusion) rather than rigid ECG thresholds. By applying refined ECG criteria, integrating AI, and changing guideline and quality metric frameworks, clinicians can better identify and treat patients at risk. The authors call for adoption of OMI in future ACS research, registries, clinical practice, and policy.

Authors: William H. Frick,Jesse TT McLaren,H. Pendell Meyers,Stephen W. Smith