What is the treatment for unstable angina according to cardiology?

Treatment of Unstable Angina According to Cardiology

The treatment of unstable angina requires immediate hospitalization with a combination of antiplatelet therapy (aspirin and clopidogrel), anticoagulation, anti-ischemic medications, and risk stratification for an early invasive or conservative management strategy. 1, 2

Initial Management

• Immediate administration of aspirin (162-325 mg) should be given to all patients with unstable angina, as it significantly reduces cardiovascular events 1, 3
• Anticoagulation should be initiated promptly with one of the following options:
  • Unfractionated heparin (UFH) 3
  • Enoxaparin (low-molecular-weight heparin) 3
  • Fondaparinux 3
  • Bivalirudin 3
• A loading dose of clopidogrel (300 mg followed by 75 mg daily) should be administered to all patients 3, 1
• Anti-ischemic therapy should begin with:
  • Sublingual or intravenous nitroglycerin for ongoing symptoms 1, 2
  • Beta-blockers in the absence of contraindications 2, 3

Risk Stratification

• Risk assessment should be performed using validated tools such as the TIMI Risk Score, which includes:
  • Age ≥65 years
  • ≥3 coronary risk factors
  • Prior coronary stenosis ≥50%
  • ST-segment deviation
  • ≥2 anginal events in prior 24 hours
  • Elevated cardiac markers
  • Aspirin use in past 7 days 1, 3
• High-risk features requiring urgent intervention include:
  • Persistent or recurrent ischemic pain
  • Dynamic ST-segment changes
  • Elevated cardiac troponin levels
  • Hemodynamic instability or heart failure 1, 3

Management Strategy Based on Risk

Early Invasive Strategy (24-48 hours)

• Recommended for high-risk patients with:
  • Refractory angina
  • Hemodynamic instability
  • Elevated cardiac biomarkers
  • Dynamic ST-segment changes
  • Diabetes mellitus
  • Reduced left ventricular function 1, 3
• Glycoprotein (GP) IIb/IIIa inhibitors (eptifibatide or tirofiban) should be administered in addition to aspirin and heparin for patients with continuing ischemia, other high-risk features, or when PCI is planned 3, 4
• The PRISM-PLUS trial demonstrated that tirofiban plus heparin reduced the composite endpoint of death, new MI, and refractory ischemia by 32% compared to heparin alone 4

Conservative Strategy

• Appropriate for lower-risk patients 1, 3
• Continue antiplatelet therapy and anticoagulation 3
• Measure left ventricular ejection fraction 3
• If LVEF is ≤0.40, diagnostic angiography is reasonable 3
• If LVEF is >0.40, a stress test is reasonable 3

Post-Angiography Management

For Patients Undergoing PCI

• Continue aspirin indefinitely 3, 1
• Administer a loading dose of clopidogrel if not given previously 3, 1
• GP IIb/IIIa inhibitor (abciximab, eptifibatide, or tirofiban) should be administered for troponin-positive and other high-risk patients 3
• Discontinue anticoagulant therapy after PCI for uncomplicated cases 3

For Patients Undergoing CABG

• Continue aspirin 3, 1
• Discontinue clopidogrel 5-7 days before elective CABG 3, 1
• Discontinue GP IIb/IIIa inhibitor (eptifibatide or tirofiban) 4 hours before CABG 3
• Continue UFH, but discontinue other anticoagulants appropriately before surgery 3

For Patients Managed Medically

• Continue aspirin indefinitely 3, 2
• Continue clopidogrel for at least 1 month and ideally up to 1 year 3
• Continue anticoagulation for the duration of hospitalization, up to 8 days 3

Common Pitfalls and Caveats

• Intravenous thrombolytic therapy is contraindicated in patients with unstable angina without ST-segment elevation 3, 1
• Immediate-release or short-acting dihydropyridine calcium antagonists (e.g., nifedipine) must be avoided in the absence of adequate beta-blockade, as they may increase adverse outcomes 3, 2
• Do not delay treatment while waiting for cardiac biomarker results 1
• Do not discharge patients with unstable angina prematurely 1
• For patients with multivessel disease and diabetes, CABG with internal mammary arteries is preferred over PCI 1