What is the management approach for acute coronary syndrome?

Management of Acute Coronary Syndrome

The management of acute coronary syndrome (ACS) requires immediate risk stratification followed by appropriate antiplatelet therapy, anticoagulation, and timely invasive strategy based on risk level to reduce mortality and morbidity. 1

Initial Assessment and Diagnosis

Immediate Evaluation

• Obtain ECG within 10 minutes of presentation
• Perform high-sensitivity cardiac troponin testing (0h/1h protocol recommended)
• Obtain echocardiography to evaluate LV function and rule out differential diagnoses
• Monitor for arrhythmias with continuous ECG monitoring

Risk Stratification

Patients should be categorized into risk groups that determine timing of invasive strategy:

Very High Risk (immediate invasive strategy <2h)

• Hemodynamic instability or cardiogenic shock
• Recurrent/ongoing chest pain refractory to medical treatment
• Life-threatening arrhythmias or cardiac arrest
• Mechanical complications of MI
• Acute heart failure with refractory angina or ST deviation
• Recurrent dynamic ST/T-wave changes, particularly with intermittent ST elevation

High Risk (early invasive strategy <24h)

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

Intermediate Risk (invasive strategy <72h)

• 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

Pharmacological Management

Antiplatelet Therapy

1. Aspirin: 250-500mg loading dose followed by 75-100mg daily maintenance

2. P2Y12 inhibitor (for 12 months unless contraindicated):

   • Ticagrelor (preferred): 180mg loading dose, then 90mg twice daily for all moderate-to-high risk patients
   • Prasugrel: 60mg loading dose, then 10mg daily (only for patients proceeding to PCI with known coronary anatomy)
   • Clopidogrel: 300-600mg loading dose, then 75mg daily (for patients who cannot receive ticagrelor/prasugrel or require oral anticoagulation)

Anticoagulation

• Unfractionated heparin or low molecular weight heparin during initial treatment
• GP IIb/IIIa inhibitors for high-risk patients awaiting angiography

Anti-ischemic Therapy

• Beta-blockers: First-line therapy, particularly for patients with ongoing chest pain
• Nitrates: For symptom relief (oral or IV)
• Calcium channel blockers: Alternative for patients with contraindications to beta-blockers

Invasive Management

Timing of Coronary Angiography

• Immediate invasive strategy (<2h): For very high-risk patients
• Early invasive strategy (<24h): For high-risk patients
• Invasive strategy (<72h): For intermediate-risk patients

Revascularization

• PCI of the culprit lesion is the preferred strategy for most patients
• CABG may be considered for patients with complex multivessel disease

Secondary Prevention

Pharmacological Therapy

• High-intensity statin therapy: Start as early as possible and maintain long-term
• Beta-blockers: Particularly in patients with reduced LV function (LVEF ≤40%)
• ACE inhibitors/ARBs: For patients with LV dysfunction, heart failure, hypertension, or diabetes
• Dual antiplatelet therapy: Continue for 12 months in most patients

Risk Factor Modification

• Smoking cessation
• Blood pressure control
• Diabetes management
• Lipid management with high-intensity statins

Special Considerations

ST-Elevation MI (STEMI)

• Requires immediate reperfusion therapy
• Primary PCI within 120 minutes of first medical contact is preferred
• If PCI not available within 120 minutes, fibrinolytic therapy should be administered

Non-ST-Elevation ACS (NSTE-ACS)

• Risk stratification determines timing of invasive strategy
• High-risk patients benefit from early invasive approach (within 24h)

Common Pitfalls to Avoid

1. Delayed ECG interpretation: ECG should be obtained within 10 minutes of presentation and immediately interpreted

2. Inadequate risk stratification: Failing to identify high-risk features that warrant urgent intervention

3. Administering prasugrel before knowing coronary anatomy: Prasugrel should not be given until coronary anatomy is known due to increased bleeding risk if CABG is needed 2

4. Delaying invasive strategy in high-risk patients: Early angiography (within 24h) reduces mortality in high-risk NSTE-ACS patients 1

5. Insufficient antiplatelet therapy: Dual antiplatelet therapy is essential for reducing recurrent events

6. Overlooking secondary prevention: High-intensity statin therapy should be initiated early and maintained long-term

The management approach for ACS has evolved significantly over time, with current guidelines emphasizing rapid diagnosis, risk stratification, and appropriate timing of invasive strategies based on risk level to optimize outcomes and reduce mortality 1.