Sinoatrial Block ECG Interpretation with Sample Strip

ECG Strip

Sinoatrial Block Rhythm Strip Features

Rate: Normal or slow
Rhythm: Irregular when SA block occurs
P Wave: Normal
PR Interval: Normal (0.12-0.20 sec)
QRS: Normal (0.06-0.10 sec)

In sinoatrial block, the impulse is delayed or blocked on the way to the atria. This creates a dropped beat which is a multiple of the P-P interval. After the dropped beat, the rhythm continues regularly. There are three types of SA blocks, based upon the length of the delay.
External Source: http://connects.catalyst.harvard.edu/Profiles/display/Concept/Sinoatrial%20Block
Harvard Med School Catalyst

Return to ECG Reference Guide Index

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
ECG Reference Guide
PracticalClinicalSkills.com