Advanced Cardiovascular Life Support Algorithms

Adult Acute Coronary Syndromes Algorithm: Step by Step

1. 1

   Patient presentation suggestive of ischemia or infarction

   • Chest discomfort or pressure, dyspnea, diaphoresis, nausea
   • May include discomfort in the arm, jaw, back, or upper abdomen
   • Some patients present with less obvious symptoms
2. 2

   EMS assessment, care, and hospital preparation

   • Assess ABCs, vital signs, mental status, SpO₂, and perfusion
   • Cardiac monitor
   • Obtain and interpret a 12-lead ECG within 10 minutes of first medical contact
   • Repeat the ECG if nondiagnostic and symptoms persist or the condition changes
   • Give aspirin 162-325 mg chewable if no contraindication
   • Notify the receiving facility / PCI-capable center as indicated
   • Be prepared to treat arrhythmia, shock, or cardiac arrest
3. 3

   Concurrent ED assessment and immediate treatment

   • Focused history and physical exam; establish IV access
   • Obtain cardiac troponin promptly; repeat testing as needed
   • Confirm aspirin was given; give it if not already administered
   • Oxygen only if hypoxic (e.g., SpO₂ <90%)
   • Nitroglycerin for ongoing ischemic discomfort if blood pressure and contraindication screen allow
   • Avoid nitrates with hypotension, suspected RV infarction, or recent PDE5 inhibitor use
4. 4

   STEMI or other ECG pattern concerning for acute coronary occlusion?

   • Yes: immediate reperfusion evaluation
   • No: continue evaluation for possible NSTE-ACS
5. 5

   Immediate reperfusion evaluation

   • Notify the STEMI / reperfusion team immediately
   • Do not wait for troponin
   • PCI preferred when available in time
   • First-medical-contact-to-device goal: ≤90 min at a PCI-capable facility; ≤120 min if transfer is required
   • If the ECG pattern is not straightforward, obtain immediate expert ECG review
   • Do not delay reperfusion for symptom treatment
   • If the anticipated first-medical-contact-to-device time is >120 min, evaluate eligible STEMI for fibrinolysis
   • Use symptom onset, diagnostic ECG findings, and the fibrinolytic contraindication checklist
   • Fibrinolysis is generally used when symptom onset is <12 h
   • After fibrinolysis, transfer promptly to a PCI-capable center
   • If reperfusion fails, perform immediate angiography and rescue PCI
   • If reperfusion succeeds, perform angiography within 2-24 hours, with PCI as indicated
6. 6

   Continue evaluation for possible NSTE-ACS

   Urgent escalation features include ongoing or recurrent ischemic symptoms, hemodynamic instability or shock, acute heart failure, dynamic ischemic ECG changes, and life-threatening arrhythmias.

   • Serial ECGs, serial troponins, symptoms, hemodynamic status, and the overall clinical picture guide the next step
   • Absence of STEMI does not mean absence of an emergency
7. 7

   Urgent escalation features present: NSTE-ACS requiring urgent escalation

   • Urgently involve cardiology
   • Determine timing of invasive evaluation
   • Immediate invasive strategy for refractory angina or hemodynamic or electrical instability
   • Continue serial ECGs, troponins, symptom treatment, and monitored care
8. 8

   No immediate escalation features

   • Continue monitored evaluation
   • Serial ECGs and serial troponins
   • Clinical reassessment and symptom treatment
   • Further risk assessment, cardiology input, and disposition per ACS pathway