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 after fibrinolysis is a bedside diagnosis using a bundle of findings: symptoms, ECG trend, and hemodynamic/electrical stability. Best ECG marker of successful fibrinolysis: at least 50% ST-segment…
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: Do not reflexively label ST depression in V1–V4 as “anterior ischemia/NSTEMI.” In ACS symptoms, posterior OMI is a major concern when the depression is most prominent in V1–V3…
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 Think proximal LAD / septal ischemia until proven otherwise when a patient with ischemic symptoms develops new RBBB + LAFB, especially with hemodynamic instability. Do not “normalize” ST…
Key Points: Left ventricular hypertrophy (LVH) with strain is one of the most common and dangerous STEMI mimics, particularly in the anterior leads, and is a frequent cause of false-positive…
Key Points: Pseudo-Wellens waves are anterior T-wave patterns that mimic the biphasic or deeply inverted T waves of true Wellens syndrome but are caused by non-LAD, non-ischemic physiology. These normal-variant…
Key Points: Clinical diagnosis, not an ECG pattern alone. Wellens syndrome requires the characteristic ECG findings plus the appropriate clinical scenario. Morphology alone is insufficient and high-risk if misapplied. Critical…
Key Points Wellens waves are anterior precordial T wave abnormalities (biphasic or deeply inverted) most often in V2–V3, occasionally extending to V1 and V4–V6. They signal a high likelihood of…
Key Points: High-risk STEMI morphology caused by fusion of the terminal QRS, J point, ST segment, and T wave into a single “triangular” deflection. Often massive apparent STE with loss…
Key Points: Normal T Wave in V1: The normal ECG typically shows a flat or inverted T wave in lead V1 in sinus rhythm. An upright T wave in V1 can…