What is the management of Acute Coronary Syndrome (ACS)?

Management of Acute Coronary Syndrome (ACS)

The management of Acute Coronary Syndrome requires immediate risk stratification followed by appropriate reperfusion therapy (primary PCI within 90 minutes or fibrinolysis within 30 minutes if PCI is unavailable), along with dual antiplatelet therapy, anticoagulation, and secondary prevention measures.

Initial Assessment and Diagnosis

• Perform 12-lead ECG within 10 minutes of first medical contact
• Obtain cardiac troponin measurements at 0 and 1-3 hours
• Classify ACS based on ECG findings:
  • ST-segment elevation: STEMI
  • No ST-segment elevation: NSTEMI/Unstable Angina (UA)
• Begin continuous multi-lead ECG monitoring for arrhythmias

Immediate Medical Therapy

For All ACS Patients:

• Antiplatelet therapy:

  • Aspirin 250-500mg loading dose, then 75-100mg daily 1, 2
  • P2Y12 inhibitor (loading dose followed by maintenance):
    • Prasugrel 60mg loading, 10mg daily (5mg if <60kg) 3
    • Ticagrelor or clopidogrel as alternatives

• Anticoagulation:

  • Low molecular weight heparin (e.g., enoxaparin 1mg/kg SC every 12 hours)
  • Or unfractionated heparin (60-70 U/kg IV bolus, 12-15 U/kg/hr) 2

• Anti-ischemic therapy:

  • Nitrates for ongoing chest pain
  • Beta-blockers (unless contraindicated)
  • Consider calcium channel blockers if beta-blockers contraindicated 1

Reperfusion Strategy

For STEMI:

• Primary PCI is preferred if available within 90 minutes of first medical contact 2
• If PCI not available within 120 minutes, administer fibrinolysis within 30 minutes of presentation 2
• Transfer to PCI-capable facility after fibrinolysis

For NSTEMI/UA:

• Risk stratify to determine timing of invasive strategy:

  • Immediate invasive strategy (<2 hours) for:

    • Hemodynamic instability
    • Recurrent/ongoing chest pain despite treatment
    • Life-threatening arrhythmias
    • Mechanical complications
    • Heart failure
    • Dynamic ST-T wave changes 1

  • Early invasive strategy (<24 hours) for:

    • Elevated troponin
    • Dynamic ST/T changes
    • GRACE score >140 1

  • Invasive strategy (<72 hours) for:

    • Diabetes mellitus
    • Renal insufficiency (eGFR <60 mL/min/1.73 m²)
    • LVEF <40% or heart failure
    • Early post-infarction angina
    • Recent PCI or prior CABG
    • GRACE score 109-140 1

Management of High-Risk Patients

• Add GP IIb/IIIa receptor blocker for high-risk patients undergoing PCI 1
• For patients with cardiogenic shock:
  • Emergency coronary angiography
  • Emergency PCI of culprit lesion
  • Consider emergency CABG if coronary anatomy not amenable to PCI
  • Perform emergency echocardiography to assess LV function and exclude mechanical complications 1
  • Routine use of intra-aortic balloon pump is not recommended 1

Special Considerations

• Elderly patients (≥75 years):

  • Apply same diagnostic and interventional strategies as younger patients
  • Adjust antithrombotic dosages based on renal function
  • Prasugrel generally not recommended due to bleeding risk 3

• Patients with diabetes:

  • Monitor blood glucose levels frequently
  • Avoid hypoglycemia 1

• Patients with renal impairment:

  • Assess kidney function by eGFR in all patients
  • Use low- or iso-osmolar contrast media at lowest possible volume 1
  • Adjust medication dosages as needed

Post-ACS Care and Secondary Prevention

• Medications:

  • Continue dual antiplatelet therapy for 12 months 2
  • Beta-blockers
  • ACE inhibitors/ARBs
  • High-intensity statins

• Risk factor modification:

  • Smoking cessation
  • Blood pressure control
  • Diabetes management
  • Dietary modification
  • Regular physical activity

• Follow-up:

  • 1-2 weeks for high-risk patients
  • 2-6 weeks for lower-risk patients 2

Common Pitfalls to Avoid

• Delaying ECG beyond 10 minutes of first medical contact
• Failing to recognize STEMI equivalents (posterior MI, new LBBB)
• Delaying reperfusion therapy
• Discontinuing dual antiplatelet therapy prematurely
• Not adjusting medication doses in elderly or renally impaired patients
• Neglecting secondary prevention strategies

The management of ACS has evolved significantly with strong evidence supporting early invasive strategies and aggressive antithrombotic therapy. Timely recognition and appropriate risk stratification remain the cornerstones of effective ACS management, with the ultimate goal of reducing mortality and improving quality of life.