Rebellion21: Time to Evolve – Redefining Coronary Ischemia – The OMI/NOMI Paradigm via Tarlan Hedayati, MD

In this 14-minute presentation from Rebellion in EM 2021, Dr. Tarlan Hedayati, MD discusses the shift from the paradigm of STEMI/NSTEMI to OMI/NOMI.

Tarlan Hedayati, MD
Emergency Medicine
Cook County Health
Twitter: @HedayatiMD

Objectives

1. Review the history of STEMI/NSTEMI designation and current OMI/NOMI paradigm
2. Discuss the risks of management decisions based on the STEMi/NSTEMI designation
2. Review the evidence regarding advantages of the OMI/NOMI paradigm

Redefining Coronary Ischemia (OMI vs NOMI)

• ST-Elevation Myocardial Infarction (STEMI) doesn’t always equal occlusion myocardial infarction (OMI)
• OMI doesn’t always manifest as ST-elevation on the ECG (i.e. hyperacute T waves, etc…)
• 2014 AHA/ACC guideline (Amsterdam et al, Circ 2014) for the management of patients with NSTEMI indicated that there are some NSTEMI patients that would benefit from:
  • Immediate invasive strategy (i.e. <2hrs)
    • Refractory Angina
    • Recurrent Angina
    • Sustained VT/VF
    • Hemodynamically Unstable
  • Early invasive strategy (i.e. 2 – 24hrs)
    • Dynamic ECG (i.e. New ST depression)
    • Rising Troponin
  • Delayed invasive strategy (i.e. 24 – 72hrs)
    • DM
    • CKD
    • EF <40%
    • CABG/PCI <6mo
    • Post-MI pain
  • Systematic Review and Meta-Analysis (Khan et al, Eur Heart J, 2017):
    • 7 studies with 40,777 patients with NSTEMI
    • 5% had an occluded culprit artery
    • These patients had increased risk of increased short-term and long-term mortality
  • Comparison of STEMI/NSTEMI vs OMI/NOMI (Meyers et al, J Emerg Med, 2021)

• • • 467 patients
    • 448 cardiac catheterization
    • 108 had OMI
    • 67 had STEMI
    • 41 patients (38%) didn’t not meet STEMI criteria but had OMI
    • Median time to cath:
    • STEMI (+) OMI: 41min
    • STEMI (-) OMI: 437min
• Retrospective Case-Control Study (Meyers et al, IJC Heart and Vasc, 2021):
  • 808 patients with suspected acute coronary syndrome
  • 49% had acute myocardial infarction
    • 33% OMI
    • 16% NOMI
  • 265 patients with OMI
    • 108 patients met STEMI criteria
    • Sensitivity = 41%
  • OMI ECG Criteria not Meeting STEMI Criteria:
    • Subtle STE: 83%
    • Reciprocal ST depression and/or negative hyperacute T waves: 82%
    • Terminal QRS distortion: 53%
    • Inferior STE and any STD/TWI in aVL: 50%
    • Hyperacute T waves: 49%
    • STD maximal in V1 – V4: 45%
    • Acute pathologic Q waves: 47%
  • DIFOCCULT Trial (Aslanger et al, IJC Heart and Vasc, 2020):
    • 1000 STEMI patients
    • 1000 NSTEMI patients
    • 1000 control patients
    • Of the 1000 NSTEMI patients, 282 (28.2%) were reclassified as OMI
    • Reclassified NSTEMI patients were more like STEMI patients than non-reclassified NSTEMI patients
      • Acute Coronary Occlusion:
        • STEMI: 85%
        • Re-Classified NSTEMI: 61%
        • Non-Re-Classified NSTEMI: 25%
      • In-Hospital Mortality:
        • STEMI: 8%
        • Re-Classified NSTEMI: 5%
        • Non-Re-Classified NSTEMI: 2%
      • Long-Term Mortality:
        • STEMI: 14%
        • Re-Classified NSTEMI: 11%
        • Non-Re-Classified NSTEMI: 4%
      • OMI/NOMI is not perfect and still missed 17% of acute coronary occlusions, but significantly better than STEMI/NSTEMI criteria

Post Peer Reviewed By: Salim R. Rezaie, MD (Twitter: @srrezaie)