Second Heart Sound and Late Systolic Click | #49
Certain heart sound configurations mimic a split second heart sound. One of these conditions is a late systolic click plus a single second heart sound (S2). Since the late systolic click occurs just before the S2, it is easy to confuse the two with a split S2. Listen carefully to the two sounds. If the first of the pair is of higher frequency and shorter duration than the second, it is a late systolic click followed by a single second heart sound. Another way of distinguishing a late systolic click from a split S2 is to move the stethoscope head to the pulmonic area. The late systolic click will disappear, and you will only hear the single S2. A late systolic click is caused by degeneration of the mitral valve leaflets. This degeneration causes the closing of the leaflets to make a "clicking" sound during late systole. On the anatomy video you will see prolapse of the anterior lateral mitral valve leaflet which is the cause of the late systolic click.Auscultation Sounds
![auscultation sound from lesson](https://mededu.azureedge.net/public/images/auscPosition-M.png)
![waveform](https://mededu.azureedge.net/public/sounds/waveforms203/49.png)
Patient Recording
![patient heart or lung sound](https://mededu.azureedge.net/public/images/auscPosition-M.png)
![Second Heart Sound and Late Systolic Click](https://mededu.azureedge.net/public/sounds/waveforms203/5013.png)
Patient Recording - Half Speed
![patient heart or lung sound](https://mededu.azureedge.net/public/images/auscPosition-M.png)
![Second Heart Sound and Late Systolic Click](https://mededu.azureedge.net/public/sounds/waveforms203/5013.png)
Position
![Patient position](https://mededu.azureedge.net/public/images/Supine.png)
The patient's position should be supine.
Listening Tips
Systole:higher-pitched click late in systole with short durationWaveform (Phonocardiogram)
Observe Cardiac Animation
Authors and Sources
Authors and Reviewers
- EKG heart rhythm modules: Thomas O'Brien.
- EKG monitor simulation developer: Steve Collmann
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12 Lead Course: Dr. Michael Mazzini, MD.
- Spanish language EKG: Breena R. Taira, MD, MPH
- Medical review: Dr. Jonathan Keroes, MD
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Heart sounds and mentorship: W. Proctor Harvey, MD
- Medical review: Dr. Pedro Azevedo, MD, Cardiology
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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
Second Heart Sound and Late Systolic Click | #49