Basics & Fundamentals
Latest
Flutter Waves (F waves)
Key Points Mechanism: Produced by a macro-reentrant circuit within the right atrium. Atrial Rate: Typically ~300 bpm (range 240–360 bpm). ECG Appearance: Characteristic saw-tooth baseline undulations without an isoelectric interval….
Electrical Alternans
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…
Pericardial Effusion
Key Point Always consider pericardial effusion in any patient with new low-voltage QRS complexes combined with sinus tachycardia. Prompt bedside ultrasound (POCUS) prevents diagnostic delays and potentially catastrophic outcomes. Classic…
Torsades de Pointes (TdP)
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…
Polymorphic Ventricular Tachycardia (PMVT)
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…
Ventricular Fibrillation (VF)
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:…
Acute Coronary Syndromes (ACS)
Key Points ECG First: The ECG is the most important initial test for suspected ACS. STAT ECGs help identify acute coronary occlusion MI (OMI) that require emergent reperfusion. Time-Sensitive Dx:…
Sodium Channel Blocker Toxicity
Key Points Recognizing the Danger: Sodium channel blocker toxicity can present with a variety of ECG changes that are critical to recognize, especially in patients with altered mental status or…
Nonsustained Ventricular Tachycardia
Key Points Definition: NSVT is defined as ≥3 consecutive ventricular beats, QRS duration >120 ms, rate typically 100-250 bpm (usually > 120 bpm), lasting less than 30 seconds without causing…
Accelerated Idioventricular Rhythm (AIVR)
Key Points Definition: AIVR is a benign, self-limited ventricular rhythm frequently observed following reperfusion in acute myocardial infarction (AMI). Rate Differentiation: Characterized by a regular wide-complex rhythm with a ventricular…
Hypocalcemia
Key Points Prolonged QTc as the Hallmark ECG Change: Hypocalcemia primarily lengthens the ST segment, leading to a prolonged QTc interval, increasing the risk of arrhythmias like Torsades de Pointes…
Acute Pericarditis
Key Points Diagnostic Challenge: Acute pericarditis symptoms and ECG findings can closely resemble STEMI/ACS, leading to frequent diagnostic uncertainty in acute care. Critical Importance: Rapid and accurate differentiation from STEMI…
QRS Fragmentation (fQRS)
Key Points Definition: QRS fragmentation (fQRS) refers to the presence of additional notches or spikes within the QRS complex, observed in at least two contiguous leads corresponding to a specific…
EMS ECGs in Acute Coronary Syndromes (ACS)
Key Points for EMS Providers: You are the first critical link in the chain of survival for ACS patients—your actions set the course for their care, directly impacting time to…
Hypercalcemia
Key Points Shortened QTc interval is the hallmark ECG finding of hypercalcemia, primarily due to a shortened ST segment duration. Hypercalcemia can mimic acute STEMI on ECG (pseudoinfarction pattern due…
ECG Evidence of Reperfusion After Occlusion
Key Points Dynamic Nature: Coronary artery occlusions can spontaneously reperfuse or re-occlude, causing rapidly changing ECG patterns. Real-Time ECG Utility: Recognizing reperfusion ECG patterns allows early identification of successful artery…
Congenital Long QT Syndrome
Key Points Congenital Long QT Syndrome (LQTS) is a group of genetic disorders characterized by a prolonged QT interval on ECG, leading to an increased risk of ventricular arrhythmias and…
Acquired Long QT Syndrome
Key Points Acquired Long QT Syndrome (LQTS) is the most common form of LQTS, resulting from medications, electrolyte disturbances, or underlying medical conditions. High-risk factors include the use of multiple…
Subtle ST Segment Elevation (OMI Pattern)
Key Points ACS Dynamics: Occluded arteries in ACS can spontaneously reperfuse and reocclude, making ECG findings variable. Limitations of Computer Interpretation: Subtle STE is often missed by computerized ECG interpretation;…
de Winter T Waves (OMI Pattern)
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). This pattern…
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.
Categories
- No categories
© 2025 ECG Weekly. All rights reserved. | Terms of Use | Privacy Policy
Powered by the member(dev) platform
Loading...