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Clinical Heart Sounds for Auscultation Training (28 heart sounds and murmurs+
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Heart Murmurs 101 for Pediatricians (Research Note)
V. Kudriavtsev

1. Flow of Referrals

Research indicates that most of the referrals to pediatric cardiologists
(Finley et al. Assessing children's heart sounds at a distance with digital recordings.
Pediatrics. 2006 Dec;118(6):2322-5.) consist of 

30% Innocent Murmur
20% Ventricular Septal Defect, VSD
11% Aortic Stenosis AS /AI
9% Mitral Valve Prolapse MVP/Mitral Regurgitation MR
7% Sub Aortic Stenosis (HOCM)
7% Pulmonary Stenosis, PS
5% Tetralogy of Fallot, ToF
9% other

Research done by D. A. Danford, M.D. (Heart Murmur in a Child: Case Study and
Commentary, Journal of Clinical Outcomes Management (JCOM) March 2002,
Vol. 9 N. 3, 146-158 ) as a part of Nebraska Defect Specific Diagnostic Accuracy
Study, 2001 shows that (among all abnormalities) VSD had 40% of all abnormalities,
Pulmonary Stenosis-19%, Aortic Stenosis -16%, Atrial Septal Defect ASD-10% ,
Patent Ductus Arteriosus 7%, Mitral Stenosis -5%

 

So from practical standpoint it is useful to master recognition of several
most statistically significant heart sound abnormalities - VSD, PS, AS and
ASD, thus covering close to 85% of all abnormals that can be encountered
in a typical patient flow.
Further improvement can be achieved by recognition of innocent systolic
murmurs - that by itself will help to "intercept" 56 to 30% of the
entire referral flow.

Thus, it would  be helpful to train pediatricians to effectively rule in
VSD, AS, PS, ASD and Innocent Murmurs.

2. Characteristic Phonocardiographic Signatures

VSD - abnormal	AS -abnormal	PS -abnormal
ASD -abnormal	Innocent Stills - normal	Innocent Flow - normal

We can see clear difference between VSD, AS, PS and innocent murmurs. 
In case of above mentioned abnormal sounds they all look like "Christmas Tree" and
have strong dominating intensity. ASD has characteristic S2 fixed split (two parts in the sound).
Innocent murmurs amplitude (intensity) is relatively small.
Normal sounds have no murmurs - just S1 and S2 -  "lub dup" pattern.

2. Practical Auscultation

With some training (achieved by repetitive listening of audio tracks) it will become
easier to detect these abnormalities by locking ear to their characteristic
high frequency "wooosh" or "wooop"  sound that is also of high intensity.

VSD = [SHHHHH_DU_DRR]
AS = [RRR_drup  or RRR_DHH]
PS = [LU_RRR_DUPdup]

ASD=[LUP_DU_DUP or LUH_RRR_DU_DUP]]
Innocent = [LUP_SHH_DUP]
Normal = [LUP_DUP]

(above sound signatures are per Don Michael, p. 383, Sect. 6 of this document,
Anthony Don Michael, MD -  Heart Auscultation, 1998)

ASD murmur has lower intensity, but characteristic fixed split S2 sound. It
has acoustic perception of "drupp" or "dudup" (LUH_RRR_DU_DUP).
These simple observations may help to rule in abnormality. Innocent murmurs
are comparatively soft and often have musical- "twangy" quality.

3. Sound Tracks for Self-Learning

According to Prof. Michael Barrett, MD,  Mastering cardiac murmurs: the power of repetition.
Chest. 2004 Aug;126(2):470-5.

repetitive listening of every heart sound for 500 times leads to a considerable improvement
of auscultation skills.

You can download sounds below, create CD or save on iPOD or MP3 player and listen
to them on a continuous basis while driving, cooking, cleaning the house, etc.

Sound recordings are from Texas Heart Institute CME Program (blue color)
and from Case Western Reserve University (black) Training Programs
 

VSD Case1   Ventricular Septal Defect

VSD Case2

Aortic Stenosis Case3a  Aortic Stenosis

Aortic Stenosis Case3b

Pulmonary Stenosis Case1 Pulmonary Stenosis

Pulmonary Stenosis Case2

ASD Fixed Split S2  Atrial Septal Defect

Normal (lub-dup_)

Innocent Still's   (Musical, provided by R. Geggel, MD)

Innocent Flow

4. Additional Clinical Sources Downloadable Heart Sound examples for self-learning

1) Cardiac Exam (Auscultation)- Case Western Reserve University

5. Comprehensive Training System

Ears ON developed by D.L. Roy, MD (pediatric cardiologist)
 

6. Comprehensive Book

Anthony Don Michael, Auscultation of the Heart a Cardiophonetic Approach,
MCGraw Hill, 1997, 404 p


7. Other publications - Library

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Copyright: 2004-2008 BioSignetics Corporation
Last modified: 01/01/08