ACS rule out algorithm for the adult patient with chest pain in the ED

Rapid ACS rule out algorithm 2024

consider other causes of chest pain in particular: PE, aortic dissection which need their own emergent work up, often including D-Dimer +/- emergent CTPA or CT aortogram
- the above may not be needed if a clear cause can be found such as pneumothorax or biliary colic
the following assumes hs-troponin levels according to Beckman Access hsTpI with gender specific normal levels of:
- ⇐ 10ng/L for women
- ⇐ 20ng/L for men
clinicians should still consider referring patients to cardiology if they are felt to be high risk for ACS but ECG and serial troponins are in the non-ACS range as outlined below

12 lead ECG ASAP

send bloods including troponin on arrival
if ST elevation suggestive of STEMI ⇒ STEMI call to cardiology
- remember other causes of ST elevation such as SAH, pericarditis, benign early repolarisation, old LV aneurysm, etc
otherwise:
- 1st troponin level:
  - if hs-TnI > 50 and appropriate clinical context for ACS ⇒ refer to cardiology as ? NSTEMI
  - Otherwise, if hs-TnI < 4 and > 3hrs from onset of pain, OR, hs_TnI < gender specific cut-off and onset of pain > 6 hrs ago
    - ⇒ ACS can be reasonably excluded (but still may need outpatient stress echo or CTCA or cardiology review if risk factors) if:
  - Otherwise for all other hsTnI scenarios, repeat troponin in 1 hour:
    - 2nd troponin level
      - if hs-TnI change is less than 4 and the 1st troponin was > 1hr from onset of pain ⇒ ACS can be reasonably excluded as above
      - if hs-TnI change is greater than 14 and appropriate clinical context for ACS ⇒ refer to cardiology as ? NSTEMI
      - if hs-TnI change is 4 to 14, or 1st troponin was < 1hr from onset of pain then send a 3rd troponin at 3 hrs from the 1st troponin:
        
        3rd troponin level:
        
        if further hs-TnI change is greater than 4 and appropriate clinical context for ACS ⇒ refer to cardiology as ? NSTEMI
        
        otherwise ACS is unlikely, consider other diagnosis (but still may need outpatient stress echo or CTCA or cardiology review if risk factors)