Cardiac Rhythms

Step 1 Rhythm Analysis ECG Interpretation

Introduction

When analyzing cardiac rhythm strips it is important to recognize what the cardiac complex represents and what is considered normal versus abnormal.
The technique and interpretation of cardiac rhythms is a combination of science and art.
The more you practice rhythm analysis the more comfortable you will be with the process involved and the intuitive aspects of interpretation.

When a normal heart is beating this is the result of electrical impulses that spread through the atria and then the ventricles in an organized, sequential manner. Atria, then ventricles, atria, then ventricles over and over again.
When analyzing the tracing you will first check R wave to R wave across the strip. If the intervals vary by 1 ½ small boxes or less the rhythm is considered regular.
If you take your own pulse now and then again in 10 minutes it is unlikely that your heart rate will be exactly the same number. This is because of a number of factors all working together in an effort to maintain our body within a specific range of “normal”, often referred to as homeostasis.
R wave to R wave analysis refers to the rhythmicity of the ventricles.
Now measure the P wave to P wave intervals. This refers to the rhythmicity of the atria.

Analyze this tracing. Its is regular or irregular?

Regular

Correct. Its is regular with constant intervals

Irregular

Incorrect.

Analyze this tracing. Its is regular or irregular?

Regular

Incorrect.

Irregular

Correct. It is irregular – changing intervals.

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