Acute Coronary Syndrome (ACS)

Definition

Acute Coronary Syndrome (ACS) is an umbrella term for conditions caused by abrupt plaque rupture and thrombus formation in a coronary artery, producing myocardial ischemia or infarction. It includes unstable angina, non-ST-elevation myocardial infarction (NSTEMI), and ST-elevation myocardial infarction (STEMI).

Clinical Presentation

Substernal crushing chest pain that may radiate to the left arm, jaw, or back; dyspnea; diaphoresis; nausea; anxiety; and a sense of impending doom. Women, elderly, and diabetics often present with atypical symptoms such as fatigue, epigastric pain, or dyspnea alone.

Diagnostics

• 12-lead ECG within 10 minutes of presentation (ST elevation, depression, or T-wave inversion)
• Serial troponin I or T
• CK-MB (less specific)
• Echocardiogram and coronary angiography

Nursing Interventions (MONA-B)

Morphine for unrelieved pain, Oxygen if SpO2 is less than 90%, Nitroglycerin for chest pain (hold if SBP less than 90), Aspirin 162 to 325 mg chewed, plus Beta-blockers and antiplatelet therapy. Prepare for PCI within 90 minutes for STEMI ('door-to-balloon' time).

NCLEX Relevance

A cornerstone medical-surgical topic. Expect priority and delegation questions involving chest pain, STEMI recognition, and thrombolytic contraindications.