Management of Non-ST-Elevation Acute Coronary Syndrome

Initial Management

The European Society of Cardiology recommends treating patients with new T-wave inversion and chest pain as having non-ST-elevation acute coronary syndrome (NSTE-ACS) and immediately initiating dual antiplatelet therapy with aspirin 75-150 mg plus clopidogrel, low-molecular-weight heparin or unfractionated heparin, beta-blocker (unless contraindicated), and nitrates for ongoing or recurrent chest pain 1, 2
The American College of Cardiology and European Society of Cardiology suggest obtaining serial troponin measurements immediately and again at 6-12 hours from symptom onset, as a single troponin measurement is insufficient to exclude myocardial infarction—myocardial injury may not be detectable in the first hours 3, 4

A 12-lead ECG should be performed immediately (within 10 minutes of presentation) and repeated with any recurrence of symptoms or at regular intervals during the observation period, according to the European Heart Journal 1, 2
New T-wave inversions, particularly when deep and symmetrical in anterior leads, often indicate critical proximal coronary stenosis and represent high-risk features, as stated by the European Heart Journal 4

High-risk features that mandate urgent coronary angiography within 24-48 hours include recurrent or persistent ischemic chest pain despite medical therapy, dynamic ST-segment changes, hemodynamic instability, major arrhythmias, diabetes mellitus, and early post-infarction unstable angina, according to the European Heart Journal 1, 2, 5, 6
If any of these high-risk features develop, continue low-molecular-weight heparin and initiate GPIIb/IIIa receptor inhibitor therapy while preparing for coronary angiography, as recommended by the European Heart Journal 1, 2

The European Society of Cardiology recommends initiating the following medications immediately upon diagnosis of NSTE-ACS: aspirin 75-150 mg daily, clopidogrel, low-molecular-weight heparin or unfractionated heparin, beta-blocker, and nitrates for persistent or recurrent chest pain 1, 2, 7

For high-risk patients, coronary angiography should be performed within 24-48 hours but does not require immediate catheterization unless severe ongoing ischemia, hemodynamic instability, or life-threatening arrhythmias are present, according to the European Heart Journal 1, 5, 6
A small subset with severe ongoing ischemia, cardiogenic shock, or malignant arrhythmias requires coronary angiography within the first hour, as stated by the European Heart Journal 1, 2