What is the management of Non-ST-Elevation Myocardial Infarction (NSTEMI)?

Management of Non-ST-Elevation Myocardial Infarction (NSTEMI)

The management of NSTEMI requires immediate administration of dual antiplatelet therapy with aspirin (150-300mg loading dose, followed by 75-100mg daily) and a P2Y12 inhibitor (preferably ticagrelor or prasugrel), along with anticoagulation and an early invasive strategy for high-risk patients. 1

Initial Assessment and Risk Stratification

• Obtain a 12-lead ECG within 10 minutes of first medical contact to distinguish between STEMI and NSTEMI 1
• Perform laboratory assessment including high-sensitivity cardiac troponin, complete blood count, and renal function tests 1
• Use risk stratification tools:
  • GRACE score: >140 indicates high risk, 109-140 indicates intermediate risk 1
  • TIMI Risk Score: higher scores correlate with increased risk of adverse outcomes 1

Immediate Pharmacological Management

Antiplatelet Therapy

• Aspirin: 150-300mg loading dose, followed by 75-100mg daily maintenance indefinitely 1, 2
• P2Y12 inhibitor: Choose one of the following:
  • Ticagrelor: Preferred for most patients (180mg loading dose, then 90mg twice daily) 1
  • Prasugrel: 60mg loading dose, then 10mg daily (avoid in patients ≥75 years or <60kg) 1, 3
  • Clopidogrel: 300-600mg loading dose, then 75mg daily (use when ticagrelor or prasugrel are contraindicated) 4, 2

Anticoagulation

• Choose one of the following anticoagulants:
  • Fondaparinux: Preferred for patients with increased bleeding risk 2
  • Enoxaparin: Alternative to fondaparinux 2
  • Unfractionated heparin (UFH): Especially if urgent PCI is planned 2
  • Bivalirudin: Consider in patients with high bleeding risk undergoing PCI 1

Anti-ischemic Therapy

• Nitrates: For ongoing chest pain, administer sublingual or IV nitroglycerin 2
• Beta-blockers: Administer within 24 hours if no contraindications (avoid in patients with signs of heart failure, low-output state, or risk for cardiogenic shock) 1
• Statins: Initiate high-intensity statin therapy as early as possible 1

Invasive vs. Conservative Strategy

Immediate Invasive Strategy (<2 hours)

• Indicated for patients with:
  • Hemodynamic instability or cardiogenic shock
  • Ongoing ischemia despite medical therapy
  • Life-threatening arrhythmias 1

Early Invasive Strategy (<24 hours)

• Recommended for high-risk patients with:
  • GRACE score >140
  • Dynamic ECG changes
  • Elevated troponin 1

Conservative Strategy

• For low-risk patients:
  • Continue antiplatelet and anticoagulant therapy
  • Perform stress testing before discharge
  • If stress test indicates high risk, proceed to angiography 2

Post-Acute Management

Medication Regimen

• Dual antiplatelet therapy: Continue for 12 months 1, 2
• Beta-blockers: Continue long-term, especially in patients with reduced left ventricular function 1
• ACE inhibitors/ARBs: Indicated for patients with left ventricular dysfunction, heart failure, hypertension, or diabetes 1
• High-intensity statins: Continue indefinitely 1
• Aldosterone antagonists: Consider for patients with LVEF ≤40% and either diabetes or heart failure 1

Risk Factor Modification

• Smoking cessation
• Blood pressure control
• Diabetes management
• Dietary modification
• Regular physical activity 1

Follow-up Care

• Schedule follow-up appointments:
  • 1-2 weeks for high-risk patients
  • 2-6 weeks for low-risk patients or those who have undergone revascularization 1
• Provide patient education about:
  • Symptoms of recurrent ischemia
  • Medication management
  • When to seek emergency care 1

Special Considerations

Patients Requiring CABG

• Continue aspirin 2
• Discontinue clopidogrel 5-7 days before elective CABG 2
• Discontinue IV GP IIb/IIIa inhibitors 4 hours before CABG 2
• Manage anticoagulants appropriately:
  • Continue UFH
  • Discontinue enoxaparin 12-24 hours before CABG
  • Discontinue fondaparinux 24 hours before CABG
  • Discontinue bivalirudin 3 hours before CABG 2

Patients with High Bleeding Risk

• Consider fondaparinux as the preferred anticoagulant 2
• Consider clopidogrel instead of more potent P2Y12 inhibitors 4
• Avoid NSAIDs (except aspirin) during hospitalization 2

The management of NSTEMI requires a comprehensive approach focusing on early risk stratification, appropriate antiplatelet and anticoagulant therapy, and timely invasive management for high-risk patients. Following these evidence-based guidelines can significantly improve outcomes and reduce mortality in patients with NSTEMI.