Atrial Rhythms

Atrial Fibrillation ECG Interpretation

Description

Atrial Fibrillation (afeb) occurs when multiple electrical impulses occur within the atria. This chaotic electrical activity results in a chaotic wave form between the QRS complexes. P waves are absent. They are replaced by lower case "f" waves. No P waves means there is no PR interval measurement.
This rapid electrical activity overwhelms the AV node causing impulses to enter the ventricular conduction system at irregular points. This results in irregular R to R intervals.

Not all fibrillatory waves are created equal. The "f" waves can be coarse (majority measure 3 mm or more) or can be fine (majority of waveforms measure less than 3 mm) to almost absent. Regardless always report your observations. Many times when a patient has "new onset" Atrial Fibrillation the patient will report with a heart rate of 160 bpm or more.

When a patient experiences A-fib, the atria are not contracting as they normally would. They are just quivering. This absence of contraction of the atria can result in a loss of cardiac output anywhere from 15 - 30% due to the absence of "atrial kick". This is why the heart rate is so high. The body is trying to maintain homeostasis.
It will be impossible to determine the atrial rate. You will only be able to analyze and report the ventricular rate.
Atrial Fibrillation with a ventricular response in excess of 100 bpm is commonly referred to as Atrial Fibrillation with “rapid ventricular response” or "uncontrolled A-fib".

Analyze this tracing using the five steps of rhythm analysis.

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Authors and 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
ECG Reference Guide
PracticalClinicalSkills.com