Key Points LBBB Does Not Exclude Acute Coronary Occlusion: LBBB alters ventricular activation, leading to expected secondary ST/T abnormalities. However, acute occlusion myocardial infarction (OMI) can and must still be…
Key Points Wide QRS Rhythms Can Mask OMI: Left bundle branch block (LBBB) and right ventricular (RV)-paced rhythms alter ventricular depolarization, producing expected secondary ST/T changes. However, acute occlusion MI…
Key Points What It Is: A rare autosomal dominant sodium channelopathy that leads to episodic muscle weakness or paralysis in the setting of elevated serum potassium. Named after “Impressive,” the…
Key Points Definition: CPVT is a rare hereditary form of polymorphic ventricular tachycardia (VT) that is often triggered by emotional or physical stress, leading to potentially fatal arrhythmias such as…
Key Points Spectrum, not one rhythm: Look for sinus brady, pauses, arrest, alternating atrial tachyarrhythmias (AF, flutter, ATach). Symptoms matter: Syncope, presyncope, fatigue usually come from cerebral/systemic hypoperfusion, especially after…
Key Points Diagnosis: Wellens syndrome is a clinical diagnosis that requires more than just the presence of Wellens waves; it necessitates a thorough history and consideration of other potential causes…
Key Points Definition: Atrial fibrillation with a slow ventricular response, usually < 60 bpm. ECG: Irregularly irregular rhythm, no discrete P waves, slow R-R intervals. Common causes: AV-nodal blockers (digoxin,…
Key Points STEMI Diagnosis and Contiguous Leads: While current guidelines typically require ST elevation (STE) in at least two contiguous leads for the diagnosis of STEMI, this practice is not…
Key Points Definition: The precordial swirl sign refers to a rotational pattern of ST-segment abnormalities across the precordial leads, suggesting a dynamic and evolving occlusion myocardial infarction (OMI). It is…
Key Points Origin: RVOT tachycardia is a monomorphic ventricular tachycardia (VT) that arises from the right ventricular outflow tract or tricuspid annulus. Population: Most commonly idiopathic, occurring in patients without…
Key Points The ECG can provide early, life-saving clues in the diagnosis of high-risk PE. Right Heart Strain: ECG signs of right heart strain in acute PE can predict which patients…
Key Points Pattern: ST elevation in aVR (≥1 mm), often with ST elevation in V1 and widespread ST depression (≥1 mm in ≥6 leads). Mechanism: Reflects global subendocardial ischemia, often…
Key Points Beyond Electrical Alternans: Although classically linked to tamponade, electrical alternans is present in fewer than 30% of confirmed cases. It’s abscence should never rule out tamponade. Low Voltage…
Key Points Coronary Occlusion After Shockable Arrest: ~30% of patients resuscitated from ventricular fibrillation (VF) arrest have an acute coronary occlusion and present with STEMI on ECG. Among patients without…
Key Points Classically associated with pericardial tamponade but seen in fewer than 30% of confirmed cases. Combination of low-voltage QRS + sinus tachycardia strongly suggests pericardial effusion/tamponade. Always perform rapid…
Key Points Definition: TdP is a specific subtype of polymorphic ventricular tachycardia associated with a prolonged QTc interval. It often presents with a “twisting” pattern on ECG but can be…
Key Points Definition: PMVT is a ventricular tachycardia characterized by beat-to-beat variations in QRS morphology, axis, and duration, reflecting multiple ventricular foci or reentrant circuits. Clinical Importance: PMVT is often…
Key Points High Risk of Missed Diagnosis: Isolated posterior occlusion MI is frequently missed due to the absence of ST elevation on standard 12-lead ECG. Instead, ST depression in V1–V3…
Key Points Rapidly Fatal Rhythm: VF is the most critical shockable cardiac arrest rhythm, requiring immediate defibrillation and high-quality CPR to prevent sudden cardiac death within minutes. Chaotic Electrical Activity:…
Key Points Most Missed STEMI: Isolated posterior MI is the most commonly missed occlusion MI due to the absence of ST elevation on standard 12-lead ECG. ECG Pattern of Posterior…
Free Content
Jump on our email list for free tips and insights delivered to your inbox monthly. No spam - just quick pearls and ECG education.