Key Points: Lateral and high-lateral STEMI often present with subtle ST elevation and are commonly missed or labeled as nonspecific ST-T changes. Small-appearing ECG changes may represent true coronary occlusion…
Key Points: Inferior STEMI is the most common STEMI subtype and is frequently complicated by right ventricular and posterior involvement. Inferior occlusion may present with classic ST elevation, subtle ischemic…
Key Points: Anterior STEMI represents large myocardial territory at risk and carries the highest mortality among STEMI subtypes. Early recognition and reperfusion are critical. LAD occlusion may present with classic…
Key Points: High risk of missed diagnosis. Isolated posterior occlusion MI is frequently missed because ST elevation is absent on the standard 12-lead ECG. Instead, posterior infarction most often presents…
Key Points: Early repolarization (ER) is a common, benign ECG pattern that most often appears in young, healthy patients. It can closely resemble acute anterior STEMI, creating a high-risk diagnostic…
Key Points: LV aneurysm pattern is a post MI scar pattern with persistent ST elevation in the prior infarct territory, usually with pathologic Q waves and a stable, non evolving…
Key Points: ST elevation is a pattern, not a diagnosis. STEMI represents one cause of ST elevation and requires correlation with ECG morphology, distribution, evolution, and clinical context. Most ED…
Key Points: Severe hyperkalemia is a true ECG chameleon. It can produce ST elevation, wide QRS complexes, axis shifts, and conduction blocks that closely mimic STEMI or ventricular tachycardia. New…
Key Points: Start by looking for STEMI, not pericarditis. The safest workflow is to actively search for occlusion MI features first, then use pericarditis features as supportive evidence. Reciprocal ST…
Key Points: STAT ECG is the first decision point in ACS. The primary purpose of the initial ECG is to identify patients who meet traditional STEMI criteria and require immediate…
Key Points: Most missed occlusion MI. Isolated posterior occlusion MI is frequently missed because the standard 12-lead ECG often lacks ST elevation. Instead, posterior injury appears as reciprocal anterior ST…
Key Points: Takotsubo (stress) cardiomyopathy is a transient, non-ischemic LV dysfunction—classically apical ballooning with basal hyperkinesis—often after emotional or physical stress. Presentation mimics occlusion MI (chest pain, ECG changes, elevated…
Key Points: ACS is dynamic. Coronary arteries can occlude, partially reperfuse, and re-occlude over minutes to hours, and the ECG can show these shifts before biomarkers do. The earliest actionable…
Key Points: Reperfusion and re-occlusion can occur spontaneously or after therapy. The ECG often reflects these changes earlier than symptoms. Most useful bedside ECG marker of reperfusion is ST-segment resolution…
Key Points: STEMI criteria alone miss some acute coronary occlusions, so look for subtle “occlusion clues,” not just traditional STEMI criteria cutoffs. Minor ST elevation under 1 mm paired with…
Key Points: ACS is a clinical syndrome: classified by ischemic symptoms + ECG + troponin. ACS exists on a continuum of unstable angina, NSTEMI, STEMI, and patients can evolve between…
Key Points: Hypomagnesemia is an important arrhythmogenic electrolyte abnormality. It increases risk of atrial and ventricular ectopy, ventricular tachycardia, and torsades de pointes, especially when QT is prolonged. The most…
Key Points: Definition & Terminology: Arrhythmogenic Cardiomyopathy (ACM), previously known as Arrhythmogenic Right Ventricular Cardiomyopathy/Dysplasia (ARVC/D), is an inherited disorder characterized by progressive fibrofatty replacement of the ventricular myocardium, predominantly…
Key Points: STEMI Equivalent: The de Winter ECG pattern is an uncommon STEMI equivalent indicative of an unstable proximal occlusion of the LAD (left anterior descending coronary artery). Treat the…
Key Points: Pacemakers treat bradyarrhythmias by delivering timed atrial, ventricular, or dual-chamber pacing when intrinsic activity is slow or absent. Know the major device types encountered in the ED: single-chamber,…