NSTEMI management algorithm

NSTEMI Diagnosis - Spotting the Clues

• Pathophysiology: Partial coronary artery occlusion → myocardial ischemia.
• Clinical Presentation: Anginal chest pain lasting >20 minutes, potentially radiating to the jaw, neck, or left arm.
• ECG Findings:
  • ST-segment depression
  • T-wave inversion
  • Can be normal
• Cardiac Biomarkers: ↑ Troponin I or T is the hallmark. Levels rise within 2-4 hours.

⭐ Serial troponin measurements are crucial; a single negative troponin at presentation does not rule out NSTEMI.

Risk Stratification - Sorting the Players

• Goal: To identify patients who benefit most from an early invasive strategy. This is guided by risk scores and key clinical features.

• Risk Scores:

  • TIMI Score: Assesses 7 factors; a score of ≥ 3 indicates high risk.
  • GRACE Score: More predictive for mortality; a score > 140 signifies high risk.

• High-Risk Features (Mandating an Invasive Strategy):

  • Refractory angina despite medical therapy.
  • Dynamic ST changes (e.g., new ST depression).
  • Hemodynamic instability (hypotension, heart failure).
  • Ventricular arrhythmias (VT/VF).

⭐ The GRACE score is a better predictor of in-hospital and long-term mortality than the TIMI score.

Initial Medical Therapy - The Drug Cocktail

Immediate treatment for NSTEMI involves a combination of drugs, often remembered by the mnemonic 📌 MONA-BASH. Note: Oxygen is only given if SpO2 < 90%, and Morphine is used cautiously for persistent pain.

• Dual Antiplatelet Therapy (DAPT):
  • Aspirin: 325 mg loading dose, then 81 mg daily.
  • P2Y12 Inhibitor: Clopidogrel, Ticagrelor (180 mg loading), or Prasugrel.
• Anticoagulation:
  • Unfractionated Heparin (UFH) or Low Molecular Weight Heparin (LMWH).
• Adjunctive Therapy:
  • Beta-blockers: Start within 24 hours if no signs of heart failure.
  • Nitrates: For ongoing chest pain.
  • High-Intensity Statin: e.g., Atorvastatin 80 mg.

⭐ Prasugrel is contraindicated in patients with a history of stroke or TIA.

Invasive vs. Conservative - The Big Decision

Central choice after risk stratification (e.g., TIMI, GRACE score). High-risk patients benefit most from an invasive approach.

• Immediate Invasive (<2h): For unstable patients.

  • Refractory angina
  • Hemodynamic instability / cardiogenic shock
  • Acute HF
  • Sustained VT/VF

• Ischemia-Guided (Conservative): Medical management, with angiography reserved for recurrent symptoms or positive stress test.

⭐ An early invasive strategy is preferred for high-risk patients (e.g., GRACE score >140) to reduce future ischemic events.

High-Yield Points - ⚡ Biggest Takeaways

• Initial management includes MONA-B (Morphine, Oxygen, Nitrates, Aspirin, Beta-blocker) and anticoagulation (e.g., Heparin).
• All patients receive Dual Antiplatelet Therapy (DAPT), typically aspirin plus a P2Y12 inhibitor.
• Risk stratify using TIMI or GRACE scores to determine invasive vs. conservative strategy.
• High-risk features warrant an early invasive strategy (angiography within 24 hours).
• Low-risk patients can be managed conservatively, often with a stress test to guide further care.