How Is Acute Myocardial Ischemia Treated?

Acute myocardial ischemia—a sudden, critical reduction in blood flow to the heart muscle—requires prompt, evidence-based intervention to prevent irreversible myocardial injury and reduce the risk of infarction. Management begins with immediate stabilization: administration of supplemental oxygen (if hypoxic), sublingual nitroglycerin to relieve coronary vasospasm and reduce preload, and aspirin (162–325 mg chewed) to inhibit platelet aggregation. Intravenous beta-blockers—such as metoprolol—are initiated unless contraindicated (e.g., acute decompensated heart failure, bradycardia, or high-grade AV block) to lower heart rate, blood pressure, and contractility, thereby decreasing myocardial oxygen demand.

Anticoagulation is essential; unfractionated heparin or low-molecular-weight heparin (e.g., enoxaparin) is administered alongside dual antiplatelet therapy (DAPT), typically aspirin plus a P2Y₁₂ inhibitor such as ticagrelor or prasugrel. Risk stratification using clinical assessment, serial cardiac biomarkers (notably high-sensitivity troponin), and electrocardiographic findings guides further management. Patients with persistent ST-segment elevation (STEMI) require urgent reperfusion—ideally primary percutaneous coronary intervention (PCI) within 90 minutes of first medical contact—or fibrinolytic therapy if PCI is unavailable within 120 minutes.

In contrast, patients with non-ST-elevation acute coronary syndrome (NSTE-ACS), including unstable angina and non-STEMI, undergo early invasive evaluation—typically coronary angiography within 24 to 72 hours—followed by revascularization (PCI or coronary artery bypass grafting) based on anatomy and risk profile. Adjunctive therapies include high-intensity statins (e.g., atorvastatin 80 mg daily), ACE inhibitors or ARBs in patients with left ventricular systolic dysfunction or hypertension, and sodium-glucose cotransporter-2 (SGLT2) inhibitors in those with comorbid diabetes or heart failure. Continuous ECG monitoring, serial troponin measurements, and close hemodynamic observation remain integral throughout the acute phase.