Non-ST Elevation Myocardial Infarction (NSTEMI)

Non-ST Elevation Myocardial Infarction (NSTEMI) represents a critical form of acute coronary syndrome (ACS), where a partial blockage in a coronary artery reduces blood flow to the heart muscle, leading to ischemia and necrosis. Unlike STEMI, NSTEMI lacks persistent ST-segment elevation on electrocardiogram (ECG), but diagnosis relies on clinical symptoms and biomarkers like troponin elevation above the 99th percentile. This condition demands urgent intervention to prevent progression to full infarction or complications such as heart failure.

Symptoms and Diagnosis

Patients typically experience chest pain or discomfort radiating to the jaw, neck, back, or arms, accompanied by shortness of breath, nausea, sweating, dizziness, or lightheadedness—symptoms mirroring unstable angina. Diagnosis involves ECG showing ST depression, T-wave inversions, or normal tracings, alongside blood tests confirming cardiac enzyme rise. Risk stratification uses tools like TIMI or GRACE scores to guide therapy urgency.

Causes and Risk Factors

NSTEMI arises from atherosclerotic plaque rupture or erosion triggering thrombus formation, often in patients with hypertension, diabetes, smoking history, dyslipidemia, or prior cardiovascular disease. It accounts for a significant portion of myocardial infarctions, emphasizing the need for lifestyle modification and secondary prevention.

Treatment Approaches

Initial management includes anti-ischemic therapy: oxygen, nitrates, beta-blockers, and analgesics. Anticoagulation with heparin or enoxaparin, plus dual antiplatelet therapy (aspirin and P2Y12 inhibitors like clopidogrel), is standard. High-risk cases undergo early invasive strategy with percutaneous coronary intervention (PCI) or coronary artery bypass grafting (CABG), alongside statins and ACE inhibitors for long-term care.