What are the initial management guidelines for patients presenting with Acute Coronary Syndrome (ACS)?

Initial Management Guidelines for Acute Coronary Syndrome (ACS)

The initial management of Acute Coronary Syndrome requires immediate diagnostic evaluation, antiplatelet therapy, anticoagulation, and risk stratification to determine the timing of invasive strategies based on the latest 2025 ACC/AHA guidelines. 1, 2

Immediate Diagnostic Approach

• 12-lead ECG within 10 minutes of first medical contact to classify as STEMI or NSTE-ACS 2
• High-sensitivity cardiac troponin testing using validated 0h/1h algorithm for rapid diagnosis 1
  • Additional testing at 3-6 hours if initial measurements inconclusive and clinical suspicion remains high
• Echocardiography to evaluate regional and global LV function and rule out differential diagnoses 1

Initial Pharmacological Management

Antiplatelet Therapy

• Aspirin 162-325mg (chewed or dissolved) immediately upon presentation 2
• P2Y12 inhibitor in addition to aspirin for 12 months 1:
  • Ticagrelor (180mg loading dose, 90mg twice daily) recommended for moderate to high-risk patients 1
  • Prasugrel (60mg loading dose, 10mg daily) for patients proceeding to PCI without contraindications 1
  • Clopidogrel (300-600mg loading dose, 75mg daily) for patients who cannot receive ticagrelor/prasugrel or require oral anticoagulation 1, 3

Anticoagulation

• Parenteral anticoagulation options 1:
  • Enoxaparin: 0.10 mg/kg loading dose followed by 0.25 mg/kg/hour for early invasive strategy
  • Fondaparinux: 2.5 mg SC daily until PCI is performed
  • Unfractionated heparin: 60 IU/kg loading dose (max 4000 IU) with 12 IU/kg/hour infusion (max 1000 IU/h)

Adjunctive Therapies

• High-intensity statin therapy as early as possible 1, 2
• Oral beta-blockers within 24 hours unless contraindicated 2
• ACE inhibitors within 24 hours for patients with pulmonary congestion or LVEF ≤40% 2
• Supplemental oxygen only if SpO2 <90% or respiratory distress 2
• Nitroglycerin (0.4mg SL every 5 minutes up to 3 doses) for symptom relief 2
• Proton pump inhibitor for patients at risk of GI bleeding on dual antiplatelet therapy 1

Invasive Strategy Timing Based on Risk

STEMI Patients

• Primary PCI preferred if available within 90 minutes (direct presenters) or 120 minutes (transfers) 2
• Fibrinolytic therapy if PCI not available within timeframe, followed by transfer for PCI within 24 hours 2

NSTE-ACS Patients

Risk-based timing for invasive strategy 1:

• Immediate invasive strategy (<2h) for very high-risk patients:

  • Hemodynamic instability or cardiogenic shock
  • Recurrent/ongoing chest pain refractory to medical therapy
  • Life-threatening arrhythmias or cardiac arrest
  • Mechanical complications of MI
  • Acute heart failure with ACS

• Early invasive strategy (<24h) for high-risk patients:

  • Rise/fall in cardiac troponin compatible with MI
  • Dynamic ST or T-wave changes (symptomatic or silent)
  • GRACE score >140

• Invasive strategy (<72h) for intermediate-risk patients:

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

Revascularization Strategy

• Complete revascularization recommended for both STEMI and NSTE-ACS 1
• Radial approach preferred over femoral approach to reduce bleeding, vascular complications, and death 1
• Intracoronary imaging recommended for PCI in patients with complex coronary lesions 1
• For cardiogenic shock, emergency revascularization of the culprit vessel is indicated, but routine PCI of non-infarct arteries is not recommended 1

Common Pitfalls to Avoid

• Delaying ECG beyond 10 minutes in suspected ACS
• Administering prasugrel when coronary anatomy is unknown 1
• Using fibrinolytic therapy in NSTE-ACS 1
• Failing to recognize posterior STEMI (ST depression in anteroseptal leads) 2
• Administering IV beta-blockers in patients with moderate-severe LV failure, pulmonary edema, bradycardia, hypotension, or reactive airway disease 2
• Administering IV ACE inhibitors within the first 24 hours due to risk of hypotension 2

Following these evidence-based guidelines will optimize outcomes by reducing mortality, morbidity, and improving quality of life for patients presenting with ACS.