• Skip to content
  • Skip to secondary menu
  • Skip to primary sidebar
  • Skip to footer

Life in the Fast Lane • LITFL • Medical Blog

Emergency medicine and critical care medical education blog

  • Libraries
  • ECG Library
  • Top 100
  • Podcasts
  • CCC
Home | ECG Library | Hypomagnesaemia

Hypomagnesaemia

by Dr John Larkin, last update February 6, 2019

↪  ECG Library Homepage

Hypomagnesaemia Overview

  • Normal serum magnesium = 0.8 – 1.0 mmol/L.
  • Hypomagnesaemia = <0.8 mmol/L

ECG changes in Hypomagnesaemia

  • The primary ECG abnormality seen with hypomagnesaemia is a prolonged QTc.
  • Atrial and ventricular ectopy, atrial tachyarrhythmias and torsades de pointes are seen in the context of hypomagnesaemia, although whether this is a specific effect of low serum magnesium or due to concurrent hypokalaemia is uncertain.
  • Nevertheless, correction of serum magnesium to >1.0 mmol/L (with concurrent correction of serum potassium to >4.0 mmol/L) is often effective in suppressing ectopy and supraventricular tachyarrhythmias, while a rapid IV bolus of magnesium 2g is a standard emergency treatment for torsades de pointes.

Example ECG

ECG Hypomagnesemia prolonged QT

Hypomagnesaemia causing long QTc (510ms)


Related Topics

  • QT interval
  • Hyperkalemia
  • Hypokalemia
  • Hypercalcemia
  • Hypocalcemia

LITFL Further Reading

  • ECG Library Basics – Waves, Intervals, Segments and Clinical Interpretation
  • ECG A to Z by diagnosis – ECG interpretation in clinical context
  • ECG Exigency and Cardiovascular Curveball – ECG Clinical Cases
  • 100 ECG Quiz – Self-assessment tool for examination practice
  • ECG Reference SITES and BOOKS – the best of the rest

Advanced Reading

  • Brady WJ, Truwit JD. Critical Decisions in Emergency and Acute Care Electrocardiography
  • Surawicz B, Knilans T. Chou’s Electrocardiography in Clinical Practice: Adult and Pediatric
  • Wagner GS. Marriott’s Practical Electrocardiography 12e
  • Chan TC. ECG in Emergency Medicine and Acute Care
  • Rawshani A. Clinical ECG Interpretation
  • Mattu A. ECG’s for the Emergency Physician
  • Hampton JR. The ECG In Practice, 6e

ECG LIBRARY 700

ECG LIBRARY

Electrocardiogram

EKG Library

About Dr John Larkin

Dr John is an Emergency Medicine Specialist MBChB FRCEM FACEM. Interest in Medical Education and Web Based Resources | + John Larkin | Twitter | ECG of the Week | LinkedIn

Reader Interactions

Leave a Reply Cancel reply

This site uses Akismet to reduce spam. Learn how your comment data is processed.

Primary Sidebar

  • Twitter
  • Vimeo
  • Facebook
  • LinkedIn
  • Twitter
  • RSS Feed

Recent Posts

FFFF Funtabulously Frivolous Friday Five Medical Trivia

Funtabulously Frivolous Friday Five 271

SMACC-UNconference 340

Join the SMACC Clinician Educators Unconference!

SMACC-Dragons-Den 340

Join the SMACC Clinician Educators Dragon’s Den!

Toxicology Library Tox Clinical Cases 340

Why so blue?

Robbert J. de Winter (1958 – ) 1

Robbert de Winter

AD iSimulate

Footer

RSS FEED  LITFL posts by EMAIL or RSS

RSS FEED  LITFL Review by EMAIL or RSS

RSS FEED  FFFF by EMAIL or RSS

#FOAMed Medical Education Resources by LITFL is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License.

Based on a work at https://litfl.com

Authors • Blog • Contact • Disclaimer

2018 Launch

  • 5,620,071 visitors

Copyright © 2019 · Powered by vocortex and iSimulate