First Heart Sound - Loud | Lessons with Audio and Video | #38

Usually, the first heart sound is slightly louder than the second heart sound when heard in the Mitral valve area. In this case the first heart sound is much louder than the second heart sound. This can be produced by a thickened, but still mobile, mitral valve. Look at the anatomy video to see the thickened mitral valve leaflets. A very loud first heart sound can be an indication of mitral stenosis.

Auscultation Sounds

Position

The patient's position should be supine.

Listening Tips

S1:Increased intensity
S2:Softer intensity than S1

Waveform (Phonocardiogram)

Observe Cardiac Animation

Notice the thickened mitral valve leaflets. The first heart sound is much louder than the second heart sound. This can be produced by a thickened, but still mobile, mitral valve.

Authors and Sources

Authors and Reviewers

EKG heart rhythm modules: Thomas O'Brien.
EKG monitor simulation developer: Steve Collmann
12 Lead Course: Dr. Michael Mazzini, MD.
Spanish language EKG: Breena R. Taira, MD, MPH
Medical review: Dr. Jonathan Keroes, MD
Heart sounds and mentorship: W. Proctor Harvey, MD
Medical review: Dr. Pedro Azevedo, MD, Cardiology
Last Update: 1/8/2023

Sources

Electrocardiography for Healthcare Professionals, 5th Edition Kathryn Booth and Thomas O'Brien
ISBN10: 1260064778, ISBN13: 9781260064773
McGraw Hill, 2019
Rapid Interpretation of EKG's, Sixth Edition
Dale Dublin
Cover Publishing Company
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
Clinical Heart Disease W Proctor Harvey, MD
Clinical Heart Disease
Laennec Publishing; 1st edition (January 1, 2009)
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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First Heart Sound - Loud | Lessons with Audio and Video | #38