×
MedSchool: Ace Your OSCEsThe Medical Company
 
 
 
 
 
GET - On the App Store
View
ECG Disease Patterns
 
 

Hypokalaemia on ECG

 
 
 
Bookmark

Overview

Potassium is important in maintaining membrane potentials, particularly in cardiac myocytes. 
Hypokalaemia, or a reduced serum potassium concentration of <3.5mmol/L, is associated with hyperpolarisation of cardiac myocytes. If severe, hypokalaemia causes abnormal ventricular automaticity which may result in ventricular arrhythmias.
  • Severity of Hypokalaemia

  • Mild - 3.0 - 3.5 mmol/L
  • Moderate - 2.5 - 3.0 mmol/L
  • Severe - <2.5 mmol/L
ECG changes are not typically seen until the potassium concentration is <3.0.
  •  
  • ECG Findings in Hypokalaemia

  • Moderate to Severe

  • PR prolongation
  • ST depression
  • T wave flattening or inversion
  • Prominent U wave (resulting in an apparent prolonged QT interval)
  • Life-Threatening

  • Torsade de pointes
  • Ventricular tachycardia
  • Ventricular fibrillation
Next Page
----------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Want more info like this?
  • Your electronic clinical medicine handbook
  • Guides to help pass your exams
  • Tools every medical student needs
  • Quick diagrams to have the answers, fast
  • Quizzes to test your knowledge
Sign Up Now
   
 
 

Snapshot: Initialising...