Electrolytes
Results:
UMMC Cases Part III: When T Waves Help Tell the Story
A 23-year-old woman presents with palpitations and lightheadedness after a spontaneous episode of regular wide complex tachycardia. Her post-conversion ECG shows anterior T wave inversions with a subtle abnormality hiding…
Hypokalemia
Key Points: Hypokalemia delays ventricular repolarization, producing progressive changes in the T-U complex before serious arrhythmias develop. ECG progression: T-wave flattening → mild ST depression → prominent U waves →…
Hypokalemia Emergencies
Key Points: Severe hypokalemia can result in an arrhythmia emergency. The major threat is ventricular tachyarrhythmias, including torsades de pointes, polymorphic ventricular tachycardia, ventricular fibrillation, and sudden cardiac death. Severe…
Hypermagnesemia
Key Points: Hypermagnesemia is uncommon and usually occurs when impaired renal magnesium clearance is combined with increased magnesium exposure, such as magnesium-containing laxatives, antacids, bowel preparations, or therapeutic magnesium administration….
Hypomagnesemia
Key Points: Hypomagnesemia is an important arrhythmogenic electrolyte abnormality. It can promote atrial and ventricular ectopy and increase susceptibility to ventricular arrhythmias, particularly when other repolarization abnormalities are present. ECG…
Hypocalcemia
Key Points: ECG hallmark: QT prolongation caused predominantly by ST-segment prolongation, usually with relatively preserved T-wave morphology. Arrhythmia risk: Severe hypocalcemia can predispose to ventricular arrhythmias, including torsades de pointes…
Hyperkalemic Periodic Paralysis (Impressive Syndrome)
Key Points: What It Is: Severe hyperkalemia can cause sudden, profound, symmetric muscle weakness or flaccid paralysis. Dr. Mattu has referred to this memorable presentation as “Impressive Syndrome,” a teaching…
Hyperkalemia Emergencies
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…
Hypercalcemia
Key Points: ECG hallmark: Shortened QT interval, primarily due to shortening of the ST segment. STEMI mimic: Severe hypercalcemia can produce apparent ST-segment elevation and a pseudoinfarction pattern, occasionally mimicking…
Hypokalemic Periodic Paralysis
Key Points: Definition: Hypokalemic periodic paralysis (HPP) is a rare disorder characterized by episodic, reversible flaccid muscle weakness associated with a shift of potassium from the extracellular space into skeletal…
STEMI vs Severe Hyperkalemia: DDx
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…
Himalayan T Waves
Key Points Tall, broad-based T–U fusion that looks like a mountain peak, usually from severe hypokalemia; think high torsades risk until proven otherwise. Hallmark is prolonged repolarization: QT appears long…
U Wave: Basics
Key Points Definition and origin: The U wave is a small deflection following the T wave, best seen in V2–V3. It likely reflects late ventricular repolarization or Purkinje repolarization. Normal…
ECG Basics & Fundamentals: causes of prolonged ST segment
A 54-year-old woman presents to the emergency department with generalized weakness and nausea. She is tachycardic but otherwise has normal vital signs. The following ECG was obtained:
Reverse Wellens Waves: not all biphasic T waves are indicative of ACS!
A 25-year-old woman presents to the emergency department with lightheadedness and palpitations for 1 week. Her symptoms worsened today with a near-syncopal episode. She is thin/frail and dehydrated in appearance….
Differential Diagnoses: a triad of long QT interval, PVCs, & ST segment depression
A 56-year-old woman presents to a busy ED dehydrated with acute gastroenteritis. She is placed in a hallway bed and treated with IV fluids and ondansetron. On reassessment the patient…
STAT ECG Diagnoses: regular wide complex tachycardia (RWCT) after succinylcholine?
A middle-age man presents to the ED with acute hypoxemic respiratory failure from multilobar pneumonia. He is intubated using etomidate and succinylcholine and noted to have a change in rhythm…
Differential Diagnoses: the most likely causes of a prolonged QT interval
A 70-year-old woman presents to the ED with upper abdominal pain and vague paresthesias. The following ECG is obtained:
Differential Diagnoses: long QTc interval
HPI: 32-year-old female with PMHx of hyperthyroidism (on carbimazole) presents with jaundice and intermittent palpitations. She has mild RUQ abdominal pain, but is otherwise well. Vitals: HR~100, BP-130/70, RR-18, afebrile. Exam:…
ECG basics and fundamentals: Prehospital STEMI activations with a review of the literature
50-year-old woman with a PMHx of DM and obesity presents with dizziness and sub-acute back pain. She also reports myalgias and anorexia. She denies any associated chest pain, and is…
ECG Tags
- A-Z
- ACS Mimics
- ACS-OMI
- Activation
- Advanced Level Curriculum
- Annual ECG Competition
- Anterior OMI
- Anterior STEMI
- Approach
- Arrest
- Arrhythmia
- Arrhythmogenic Cardiomyopathy
- Artifact
- ARVC
- ARVD
- Atrial Parasystole
- Attending
- AV Block
- aVF
- aVL
- aVR
- Axis
- Barcelona
- Basics
- Bix Rule
- Board Review
- Bradyarrhythmia
- Cath Lab
- Chest Pain
- Clumped Beats
- Competition
- Conduction
- Core
- Core Level Curriculum
- Critical ECG Patterns
- Curriculum
- DDx
- Delta
- Devices
- Diagonal Branch Occlusion
- Differential Diagnoses
- Diffuse ST Elevation
- Documentation
- Early Repolarization
- ECG Interpretation
- ECG Localization
- ECG Variant
- Education/Teaching
- Electrolytes
- Emergencies
- Emergent Cath Lab Activation
- EMS
- Expert Level Curriculum
- Flutter
- Flutter Waves
- Foundations Level Curriculum
- Guidelines
- High-Lateral STEMI
- Hub
- Hyperacute T waves
- Hypercalcemia
- Hyperkalemia
- Hypermagnesemia
- Hypocalcemia
- Hypokalemia
- Hypomagnesemia
- Hyponatremia
- Hypothermia
- I
- II
- Index
- Inferior OMI
- Inferior STEMI
- Intervals
- Irregular
- Ischemia
- Ischemia & Infarction
- J point
- J Waves
- JT
- Junctional Rhythm
- Juvenile T wave
- LAD Occlusion
- Lateral STEMI
- LBBB
- LCx Occlusion
- Lead Placement
- Left Atrial Enlargement (LAE)
- Life Savers
- LV an
- LV Aneurysm
- LVAD
- Mastery Level Curriculum
- Metabolic
- Mimics
- Morphology
- Narrow QRS
- Occlusion MI
- OMI Pattern
- Orthodromic AVRT
- Osborn Waves
- P Wave
- Paced Rhythms
- Pacemaker/ICD
- Paramedics
- Pauses
- PE
- Pediatrics
- Pericardial
- Pericarditis
- PGY-1
- PGY-2
- PGY-3
- PGY-4
- Post-Arrest
- post-arrest STEMI
- Post-Cardiac Arrest
- Posterior Extension
- Posterior MI
- Posterior STEMI
- potpourri
- PR
- Preexcitation
- Premature Complexes
- Prolonged QT
- Pulmonary Embolism
- Pulse-Tapping Artifact
- PVCs
- Q Wave
- QRS
- QT
- R Waves
- RAD
- Rate
- RBBB
- RCA Occlusion
- Regular
- Reperfusion
- Rhythm
- Right Atrial Enlargement (RAE)
- RR
- S Waves
- S1Q3T3
- Segments
- Seizure
- Serial ECGs
- Sgarbossa
- Shock
- South African Flag Sign
- ST
- ST Depression
- ST Elevation
- STEMI
- STEMI Equivalent
- STEMI Mimics
- STEMI Negative OMI
- Stepwise
- Stroke
- Structural
- Students
- SVT
- Syncope
- T Wave Inversion
- T Waves
- Tachyarrhythmia
- Tachycardia
- Tamponade
- Terminal QRS Distortion
- Toxicology
- TP
- Traditional STEMI Criteria
- U Waves
- Unstable
- V1-V4
- V2
- V5
- V6
- Vectors
- Ventricular Repolarization
- Ventricular Rhythms
- Ventricular Tachycardia
- Voltage
- Waveforms
- Wide QRS
- Workflow
- WPW
© 2026 ECG Weekly. All rights reserved. | Terms of Use | Privacy Policy
Powered by the member(dev) platform
Loading...