First and Second Heart Sounds - Normal and Unsplit
Virtual Auscultation
        
The patient's position is supine.
Lesson
This is a normal first and second heart sound at 60 beats per minute. You are auscultating at the Mitral valve area (Apex). The first heart sound has slightly greater intensity than the second heart sound.- The first heart sound is produced by the closing of the mitral and tricuspid valve leaflets.
 - The second heart sound is produced by the closing of the aortic and pulmonic valve leaflets.
 - The second heart sound is unsplit when the subject is holding his or her breath at peak expiration.
 
Waveform
Heart Sounds Video
The first heart sound is produced by the closing of the mitral and tricuspid valve leaflets. 
The second heart sound is produced by the closing of the aortic and pulmonic valve leaflets.
Authors and Sources
Authors and Reviewers
- 
                    Heart sounds by Dr. Jonathan Keroes, MD and David Lieberman, Developer, Virtual Cardiac Patient.
 - Lung sounds by Diane Wrigley, PA
 - Respiratory cases: William French
 - 
                    David Lieberman, Audio Engineering
 - 
                    Heart sounds mentorship by W. Proctor Harvey, MD
 - Special thanks for the medical mentorship of Dr. Raymond Murphy
 - Reviewed by Dr. Barbara Erickson, PhD, RN, CCRN.
 - 
                    Last Update: 12/11/2022 
 
Sources
- 
                        Heart and Lung Sounds Reference Library
                    
                    Diane S. Wrigley
Publisher: PESI - 
                    Impact Patient Care: Key Physical Assessment Strategies and the Underlying Pathophysiology
                    
Diane S Wrigley & Rosale Lobo - Practical Clinical Skills: Lung Sounds
 - Essential Lung Sounds
                    Diane S. Wrigley, PA-C
Published by MedEdu LLC - PESI Faculty - Diane S Wrigley
 - 
                        Case Profiles in Respiratory Care 3rd Ed, 2019
William A.French
Published by Delmar Cengage - Essential Lung Sounds
                    by William A. French
Published by Cengage Learning, 2011 - Understanding Lung Sounds
                    Steven Lehrer, MD
 - Clinical Heart Disease
                    W Proctor Harvey, MD
Clinical Heart Disease
Laennec Publishing; 1st edition (January 1, 2009)