SPC365

Changing the Paradigm in Acute Coronary Syndromes: From STEMI vs. NSTEMI to OMI vs. Non-OMI

Session: SESSÃO DE COMUNICAÇÕES ORAIS 04 - INOVAÇÃO EM CUIDADOS INTENSIVOS: NOVAS INTERVENÇÕES EM CHOQUE CARDIOGÉNICO E SÍNDROMAS CORONÁRIAS AGUDAS
Speaker: Andre Lobo

Congress: CPC 2025
Topic: E. Coronary Artery Disease, Acute Coronary Syndromes, Acute Cardiac Care
Theme: 13. Acute Coronary Syndromes
Subtheme: 13.3 Acute Coronary Syndromes – Diagnostic Methods
Session Type: Comunicações Orais
FP Number: ---
Authors: André Lobo; Francisco Sousa; Francisca Nunes; Marta Catarina Almeida; Fábio Nunes; Marta Leite; Inês Neves; Inês Rodrigues; António Gonçalves; Ricardo Fontes-Carvalho

<p style="text-align:justify"><span style="font-size:11pt"><span style="font-family:Aptos,sans-serif"><strong><span style="font-family:&quot;Calibri&quot;,sans-serif">Introduction: </span></strong><span style="font-family:&quot;Calibri&quot;,sans-serif">Occlusion Myocardial Infarction (OMI) is an emerging classification in acute coronary syndromes (ACS) that challenges the traditional STEMI. OMI emphasizes the identification of coronary occlusion through more subtle ECG changes. Advocates argue that this could improve the identification of patients who need urgent revascularization. OMI is defined by the presence of TIMI flow &le;2 and/or significantly elevated troponin levels (Troponin T &gt;1000 ng/L or Troponin I &gt;5000 ng/L) with regional wall motion abnormalities. In this study, we reclassified ACS patients using the OMI paradigm and analyzed their clinical characteristics and outcomes to explore the potential impact of this classification.</span></span></span></p>

<p style="text-align:justify"><span style="font-size:11pt"><span style="font-family:Aptos,sans-serif"><strong><span style="font-family:&quot;Calibri&quot;,sans-serif">Methods: </span></strong><span style="font-family:&quot;Calibri&quot;,sans-serif">We conducted a retrospective one-year analysis of ACS patients. We analyzed clinical, angiographic, and imaging data, stratifying patients into STEMI, NSTEMI-OMI, and NSTEMI-NON OMI groups.</span></span></span></p>

<p style="text-align:justify"><span style="font-size:11pt"><span style="font-family:Aptos,sans-serif"><strong><span style="font-family:&quot;Calibri&quot;,sans-serif">Results: </span></strong><span style="font-family:&quot;Calibri&quot;,sans-serif">We analyzed 336 ACS patients, including 196 STEMI and 134 NSTEMI/UA cases. Among NSTEMI/UA patients, 38.8% were classified as OMI, with 25% presenting TIMI flow &le;2.</span></span></span></p>

<p style="text-align:justify"><span style="font-size:11pt"><span style="font-family:Aptos,sans-serif"><span style="font-family:&quot;Calibri&quot;,sans-serif">The median time to angiography was 1 hour in STEMI patients, significantly shorter than the 10.5 hours in NSTEMI-OMI patients (p &lt; 0.001), and 12 hours in NSTEMI-NON OMI patients.</span></span></span></p>

<p style="text-align:justify"><span style="font-size:11pt"><span style="font-family:Aptos,sans-serif"><span style="font-family:&quot;Calibri&quot;,sans-serif">Median Left ventricular ejection fraction (LVEF) at discharge was lower in NSTEMI-OMI patients (51%) compared to NSTEMI-NON-OMI (57%) (p &lt; 0.001). This difference persisted at 12 months (p = 0.002).</span></span></span></p>

<p style="text-align:justify"><span style="font-size:11pt"><span style="font-family:Aptos,sans-serif"><span style="font-family:&quot;Calibri&quot;,sans-serif">Median peak troponin T levels were higher in NSTEMI-OMI patients (1777 ng/L) compared to NSTEMI-NON OMI patients (217 ng/L) (p &lt; 0.001). STEMI patients showed trends toward higher troponin levels and lower LVEF than NSTEMI-OMI, but these differences were not statistically significant.</span></span></span></p>

<p style="text-align:justify"><span style="font-size:11pt"><span style="font-family:Aptos,sans-serif"><span style="font-family:&quot;Calibri&quot;,sans-serif">Clinical event rates at 12 months were low across all groups, with no significant differences.</span></span></span></p>

<p style="text-align:justify"><span style="font-size:11pt"><span style="font-family:Aptos,sans-serif"><strong><span style="font-family:&quot;Calibri&quot;,sans-serif">Discussion: </span></strong><span style="font-family:&quot;Calibri&quot;,sans-serif">Our findings show that NSTEMI-OMI patients resemble STEMI patients, suggesting they may benefit from an approach similar to STEMI care. NSTEMI-OMI patients faced longer delays to angiography, though times in this cohort were still shorter than usual benchmarks, which could underestimate the potential impact of reclassification. </span></span></span><span style="font-size:11pt"><span style="font-family:Aptos,sans-serif"><span style="font-family:&quot;Calibri&quot;,sans-serif">While the OMI paradigm is promising, it faces challenges in application. Unlike STEMI, it lacks randomized validation, and ECG criteria are not fully standardized. The troponin thresholds used to define OMI may contribute to overclassification, as seen in our cohort with a significant percentage of patients classified as OMI despite normal TIMI flow. AI-driven tools capable of detecting subtle ECG changes could complement this paradigm, improving early diagnosis and intervention.</span></span></span></p>

<p style="text-align:justify"><span style="font-size:11pt"><span style="font-family:Aptos,sans-serif"><strong><span style="font-family:&quot;Calibri&quot;,sans-serif">Conclusion:</span></strong><span style="font-family:&quot;Calibri&quot;,sans-serif"> The OMI paradigm highlights critical gaps in ACS management and has the potential to improve risk stratification. Further validation is essential to refine its application and maximize its clinical impact.</span></span></span></p>