Quick Chart
  • Acute coronary syndrome (ACS) represents a continuum of clinical presentations sharing common pathology, ranging from worsening angina through to ST-elevation MI (STEMI).
  • Most patients present with prolonged (>10mins) or recurrent central chest discomfort described as tightness, heaviness, squeezing or crushing sensation.  The absence of these symptoms does not rule out ACS.
  • Patients suffering from Acute Coronary Syndromes do not always present with chest pain, and are subsequently frequently misdiagnosed

Read the complete article; Acute Coronary Syndrome in the Medical Library > Pathophysiology.

Clinical Presentation
  • Chest pain or discomfort of presumed cardiac origin
  • Acute or Sub-acute shortness of breath with no clear reason or cause (up to ⅓ of ACS patients may present without chest pain).

Other signs and symptoms associated with atypical ACS presentation may include:

  • Inter-scapula pain
  • Epigastric pain
  • Dizziness, Lightheadedness or Transient Loss of Consciousness
  • Unexplained upper limb / neck discomfort
  • Nausea / Vomiting with no obvious cause
  • Palpitations / dysrhythmias
  • Weakness / Malaise

Officers should have a low threshold for performing an ECG when any of the above symptoms are found.

Exclusion Criteria
Exclusion Criteria
Risk Assessment
  • Suspicion of acute myocardial ischaemia (AMI) is based entirely on field history. A normal-looking ECG does not rule out ACS.
  • Glyceryl Trinitrate (GTN) administration can precipitate severe hypotension in susceptible patients however it is a rare occurrence.
  • Limit patients exertion as much as is practically possible.
  • LBBB with associated chest pain should be treated as acute until proven otherwise.
  • Patients with a history of diabetes have an increased risk of presenting without chest pain in ACS. Officers should have a low threshold for performing an ECG.
Primary Care
Intermediate Care (EMT / Level 2)
  • Apply cardiac monitor if trained and authorised.
  • Administer aspirin
  • Administer GTN early (if pain is ongoing and provided GTN not contraindicated)
  • Pain relief: If pain >3/10 post 1x spray of GTN, administer Methoxyflurane
  • Ondansetron if required
  • Monitor patient continuously, recording full observations every 10 minutes (or 5 minutes if time critical)
  • Transport Priority 1 if patient time critical, pre-notifying receiving facility
Advanced Care (AP)
  • 12 lead ECG; transmit telemetry to receiving hospital as indicated
    • Multiple 12-lead ECG’s are advocated and may capture evolving changes. If the initial ECG is not diagnostic of a STEMI but the patient remains symptomatic and clinical suspicion for ACS remains high, the ECG should be repeated at least every 15 minutes.
  • Aspirin
  • Early Glyceryl Trinitrate (GTN)
  • Analgesia (where GTN has failed to relieve the chest pain completely)
  • Vascular access; obtain pre-hospital blood sample
  • Ondansetron if required
  • Administer heparin if the patient has a STEMI confirmed by the receiving hospital and patient is going direct to Cardiac Catheterisation Lab
STEMI Inclusion Criteria
  • Symptom onset < 12 hours
  • Mobile and independent ADLs
  • GCS15
Indications for Transmission
  • Monitor reads "ACUTE MI" or "Meets STEMI criteria" OR
  • ST elevation ≥ 1mm in 2 contiguous limb leads OR
  • ST elevation in ≥ 2mm in 2 contiguous chest leads OR
  • Symptomatic acute left bundle branch block
Critical & Extended Care (CCP, PSO)
  • As per Advanced Care (AP) guidelines
Additional Information
  • Clinical Deterioration
  • Dysrhythmias
  • Cardiac arrest

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