Introduction Part 1 ECG Interpretation #314
Introduction
- Cardiac rhythms are typically named by the site of origin or heart structure where the problem is occurring
- These junctional dysrhythmias primarily affect the P wave.
- Electrical impulses formation and flow in a normal heart follow a forward or antegrade flow through the atria. This results in the upright P wave we see with Sinus rhythms.
- With junctional rhythms, the impulse is initiated in the AV junction. This impulse point results in a backward or retrograde flow of electricity during atrial depolarization.
- This change in the flow of electricity results in an inverted P wave. This morphologic feature is unique to Junctional complexes and rhythms.
Inverted P Wave
- The result of this retrograde depolarization is the classic inverted P wave.
- Because the electrical impulse causing atrial depolarization may come from anywhere in the AV junction. This can affect the location or coordination with the QRS complex.
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Authors and Sources
Authors and Reviewers
- ECG heart rhythm modules: Thomas O'Brien.
- ECG monitor simulation developer: Steve Collmann
-
12 Lead Course: Dr. Michael Mazzini, MD.
- Spanish language ECG: Breena R. Taira, MD, MPH
- Medical review: Dr. Jonathan Keroes, MD
- Medical review: Dr. Pedro Azevedo, MD, Cardiology
- Last Update: 11/8/2021
Sources
-
Electrocardiography for Healthcare Professionals, 6th Edition
Kathryn Booth and Thomas O'Brien
ISBN10: 1265013470, ISBN13: 9781265013479
McGraw Hill, 2023 -
Rapid Interpretation of EKG's, Sixth Edition
Dale Dublin
Cover Publishing Company -
EKG Reference Guide
EKG.Academy -
12 Lead EKG for Nurses: Simple Steps to Interpret Rhythms, Arrhythmias, Blocks, Hypertrophy, Infarcts, & Cardiac Drugs
Aaron Reed
Create Space Independent Publishing -
Heart Sounds and Murmurs: A Practical Guide with Audio CD-ROM 3rd Edition
Elsevier-Health Sciences Division
Barbara A. Erickson, PhD, RN, CCRN -
The Virtual Cardiac Patient: A Multimedia Guide to Heart Sounds, Murmurs, EKG
Jonathan Keroes, David Lieberman
Publisher: Lippincott Williams & Wilkin)
ISBN-10: 0781784425; ISBN-13: 978-0781784429 - Project Semilla, UCLA Emergency Medicine, EKG Training Breena R. Taira, MD, MPH
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ECG Reference Guide
PracticalClinicalSkills.com