Key Points: Definition: Critical ECG patterns represent time-sensitive, life-threatening cardiac or systemic conditions that demand immediate recognition to prevent death or irreversible organ injury. These are the “can’t-miss” ECGs. Goal:…
Key Points: The ECG’s primary role in ACS is detecting acute coronary occlusion. Acute coronary occlusion myocardial infarction (OMI) is a time-critical diagnosis that requires immediate reperfusion. Time is myocardium….
Key Points: Traditional STEMI criteria miss many acute coronary occlusions. A substantial proportion of true OMIs do not meet classic millimetric STEMI thresholds. OMI is a pathophysiologic diagnosis, not an…
Key Points: The QT interval reflects the time it takes for total ventricular depolarization and repolarization (Q wave onset to T wave end). QT prolongation increases the risk of torsades…
Key Points: Prolonged QTc is the hallmark ECG change in hypocalcemia, driven mainly by ST-segment prolongation with relatively normal T-wave shape. Hypocalcemia can increase arrhythmia risk, including TdP, but TdP…
Key Points: Baseline ECG abnormalities do not protect patients from occlusion MI. They increase miss rates because they distort the ST segment and T waves. The core question is not…
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 Pattern vs syndrome: WPW pattern = pre-excitation on ECG without symptoms. WPW syndrome = pattern plus tachyarrhythmia symptoms (palpitations, syncope, “seizure,” aborted sudden cardiac arrest). Mechanism: Congenital accessory…
Key Points: Consistency saves lives: Use a repeatable ECG routine to reduce misses in chaotic settings. Many valid methods exist. Pick an order that fits your acute-care workflow and do…
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: Pattern, not a STEMI equivalent. ST elevation in aVR (≥1 mm), often with ST elevation in V1 and diffuse ST depression (≥1 mm in ≥6 leads), represents high-risk…
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 Mimics Several Life-Threatening Conditions: Severe hyperkalemia is one of the most dangerous ECG mimics in emergency medicine. It can resemble unstable bradyarrhythmias, VT, STEMI, and pacemaker…
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…