Second Degree Heart Block Type II ECG Interpretation #316
Description
- The hallmark of this dysrhythmia is a constant P-R interval with missing QRS complexes.
- This dysrhythmia may present in a couple of different ways.
- A. QRS complexes occurring in a specific pattern in a ratio with the P waves. This is often referred to as 2:1 or 3:1 block depending upon the ratio of P waves to each QRS complex.
- B. QRS complexes occur in a more unstable, unpredictable manner.
- Either presentation requires immediate reporting due to its potential for conversion to Third Degree (Complete) Heart Block.
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B.
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Practice Strip
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Analyze this tracing using the five steps of rhythm analysis.
Show Answer
- Rhythm: Atria and Ventricles - Regular
- Rate: Atria – 125, Ventricles - 41
- P Wave: Upright
- PR interval: 0.14 sec
- QRS: 0.06
- Interpretation: Second Degree Heart Block Type II, 3:1
Practice Strip #2
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Analyze this tracing using the five steps of rhythm analysis.
Show Answer
- Rhythm: A – Regular, V - Irregular
- Rate: Atria – 68, Ventricles - 40
- P Wave: Upright
- PR interval: 0.16 sec
- QRS: 0.08
- Interpretation: Second Degree Heart Block Type II
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