Troponin

• High-sensitivity cardiac troponin
  • overcomes early “troponin blind” period
  • allows rapid rule-in, rule-out protocols → impacts ED workflow
  • most will be + within 6 hrs
• ‎single sample r/o only if patient’s last had CP > 6 hrs ago
• ‎Risk scores
• ⚠️ late presentation MI with low hs-cTn may have a small delta for troponin change

Troponin Elevation

flowchart TD
    A[Elevated Troponin] --> B{Rise and/or fall}
    A --> C[Flat/No change]
    C --> D(Chronic<br>Structural ♥ dz, CKD, etc.)
    B --> |Acute Ischemia| E[Acute MI]
    B --> |≠ acute Ischemia| F[Myocardial injury]

• Elevated troponin

  • no CC/MCC
  • non cardiac rise in troponin, e.g. rhabdomyolysis, sepsis, etc.

• Type 2 NSTEMI

  • MCC
  • Elevated troponin that is probably cardiac-related, but not due to primary plaque rupture, i.e. someone with underlying CAD who presents with Hypertensive Crisis, sepsis, HF exacerbation, severe anemia, etc.

• Type 1 NSTEMI

  • MCC
  • Plaque rupture, needs a stent or has documented severe lesions, or has echo WMA
  • This counts as an MCC and also outcomes are reportable.
  • Activates NSTEMI care pathway for accreditation → echo within 30 days, cardiac rehab, etc.

• Demand ischemia

  • CC
  • Not an MI. Use this in a patient with ECG changes or chest pain, but without troponin elevation.

• Don’t call everything an “NSTEMI”:

  • A lot of type 2 NSTEMI patients are really sick from non-cardiac illnesses and if they die or get readmitted then incorrectly makes outcomes look worse.