On occasion the first heart sound can be made up of two separate sounds separated by a very small interval (20-30 milliseconds).
The Mitral component (caused by closure of the Mitral valve) comes first and is louder than the Tricuspid component (caused by closure of the Tricuspid valve).
A minimally split first heart sound is a normal variation of the first heart sound.
First Heart Sound (Minimally Split) Audio
Patient Sounds
Half Speed Patient Sounds
Technique
The patient's position should be supine.
Auscultation Tips
S1:Minimal splittingSound Wave
Observe Cardiac Animation
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
First Heart Sound (Minimally Split) | #39
