Immediate Management of Non-ST-Elevation Acute Coronary Syndrome (NSTE-ACS)

Immediate Actions

The American Heart Association recommends immediate emergency department evaluation with continuous cardiac monitoring, serial troponins, aspirin administration, and preparation for urgent coronary angiography for patients with high-risk presentation of ongoing ischemic chest pain unresponsive to nitroglycerin with ST depressions on ECG 1, 2
The American College of Cardiology suggests activating emergency medical services (EMS) immediately for patients with suspected NSTE-ACS, as they should not drive themselves or be transported by family 1, 3

The American College of Cardiology recommends administering aspirin 162-325 mg (chewed, non-enteric coated) immediately unless true allergy exists, as it is the single most important initial intervention for mortality reduction 1, 3, 4
The American Heart Association suggests obtaining 12-lead ECG within 10 minutes of arrival and performing serial ECGs every 15-30 minutes during the first hour to evaluate for active ischemia 2
The European Society of Cardiology recommends establishing IV access and drawing initial cardiac troponin (preferably high-sensitivity troponin I or T), with repeat measurement at 3-6 hours to distinguish NSTEMI from unstable angina 2

The American College of Cardiology recommends calculating TIMI Risk Score using age ≥65 years, ≥3 CAD risk factors, prior coronary stenosis ≥50%, ST deviation on ECG, ≥2 anginal events in 24 hours, aspirin use in prior 7 days, and elevated cardiac biomarkers, as a score ≥3 indicates intermediate-to-high risk requiring invasive management 2
The European Heart Journal suggests that patients with multiple high-risk criteria, including ongoing chest pain despite medical therapy, ST-segment depression, and pain radiating to left arm, should undergo early invasive strategy (coronary angiography within 24-48 hours) 2, 7

The American College of Cardiology recommends initiating dual antiplatelet therapy immediately with aspirin 162-325 mg loading dose and a P2Y12 inhibitor, such as ticagrelor 180 mg loading dose, for patients with NSTE-ACS managed with early invasive strategy 1, 4, 5
The European Society of Cardiology suggests starting parenteral anticoagulation with either low molecular weight heparin (LMWH) or unfractionated heparin (UFH) for patients with NSTE-ACS 7

The American Heart Association recommends never administering NSAIDs other than aspirin, as they increase major adverse cardiac events, and discontinuing them immediately if already being used 4, 5
The American College of Cardiology suggests not using supplemental oxygen unless oxygen saturation <90% or respiratory distress is present, as routine high-flow oxygen in uncomplicated ACS may be harmful 4, 5