Heart Murmur Chart

[Sumo Embed - 4dc64aa4f0231c9c7e39a987a7ec5903da91764e46cdf6775687c9953d115a5a]

-

The podcasts above and article below share different information. Listen and read to both to get the most out of this post!

-

We all know that whether you are a student, a new practicing clinician, or a seasoned clinician; heart murmurs can be tough!  Sometimes it can be as easy as having a handheld “heart murmur chart”, that lays out the types of murmurs, where they are heard, and what maneuvers can accentuate them. Today we will be covering several types of murmurs and putting together a solid reference/heart murmur chart for your use in school and as a clinician.

 

Where are the Valves and Where Do I Listen?

So, one of the first things we need to know is where to listen on the chest wall and what valve that area corresponds with. The five main areas are:

  1. The right 2nd intercostal space at the sternal border, which relates to the aortic valve.
    1. R Upper Sternal Border
  2. The left 2nd intercostal space at the sternal border, which relates to the pulmonic valve.
    1. L Upper Sternal Border
  3. The left 3rd intercostal space at the sternal border which is Erb’s point.
    1. Erb’s Point
  4. The Left 4th intercostal space at the sternal border which is over the tricuspid valve.
    1. L Lower Sternal Border
  5. The left 5th intercostal space at the mid-clavicular line, which is over the mitral valve.
    1. Apex

A handy Mnemonic to remember the order of the valves is: “Apple Pie Tastes Mmmmm”

              • A – Aortic
              • P – Pulmonic
              • T – Tricuspid
              • M - Mitral

 

Heart Auscultation Figure
http://www.stethographics.com/heart/main/sites.htm

 

Grading Murmurs

Additionally, we should be able to grade murmur severity based on the auscultation of heart sounds.  Heart murmur sounds are graded on a scale of 1-5 based on their intensity; as seen in the table below.

Grading of the Intensity of Heart Murmurs

What Does a Murmur Mean?

Patient’s may ask you; what does the diagnosis of a heart murmur mean?  Being able to explain the meaning of each murmur type, especially when put on the spot can be difficult, and often requires further evaluation with an echocardiogram.  However, depending on when the murmur is occurring in the cardiac cycle (systole vs. diastole), over what valve, and what types of maneuvers accentuate it, you can perhaps narrow down your list of options. 

 

Pathophysiology --> Increasing AFTERLOAD

In general, there are several different positions that will increase or decrease heart murmur sounds.  The hand grip maneuver will increase the afterload, which will ultimately increase the murmurs:

  • Aortic Regurgitation
  • Mitral Regurgitation
  • Ventricular Septal Defect

Hand grip will decrease the murmurs:

  • Hypertrophic obstructive cardiomyopathy
  • Mitral valve prolapse

 

Pathophysiology --> Increasing PRELOAD

The squatting maneuver increases the preload of the heart.  Increasing preload (squatting) increases the following murmurs:

  • Aortic Stenosis
  • Mitral Stenosis
  • Aortic Regurgitation
  • Mitral Regurgitation.

Increasing preload (squatting), decreases the following murmurs:

  • Hypertrophic Obstructive Cardiomyopathy
  • Mitral Valve Prolapse

 

Pathophysiology --> Decreasing PRELOAD

Next, the ever-popular Valsalva maneuver.  This decreases preload of the heart. Increasing preload (Valsalva), increase the following murmurs:

  • Hypertrophic Obstructive Cardiomyopathy
  • Mitral Valve Prolapse

 

Whereas, decreasing preload (the Valsalva maneuver), decreases the following murmurs:

  • Aortic Stenosis
  • Mitral Stenosis
  • Aortic Regurgitation
  • Mitral Regurgitation
  • Ventricular Septal Defect

 

Special Maneuvers -->Standing Quickly

Standing quickly!  How does this affect heart murmur sounds?  When abruptly standing, this decreases preload and has the same effect as the Valsalva maneuver

 

So again, standing abruptly will increase the murmurs:

  • Hypertrophic Obstructive Cardiomyopathy
  • Mitral Valve Prolapse

 

And will decrease the murmurs:

  • Aortic Stenosis
  • Mitral Stenosis
  • Aortic Regurgitation
  • Mitral Regurgitation
  • Ventricular Septal Defect

Special Maneuvers --> Left lateral Decubitus

The left lateral decubitus position will accentuate mitral murmurs, such as:

  • Mitral Stenosis
  • Mitral Regurgitation

 And causes S3 and S4 to accentuate.

 

Special Maneuvers --> Sitting Up Leaning Foreword

Sitting up & leaning forward will accentuate aortic murmurs, such as:

  • Aortic Stenosis
  • Aortic Regurgitation

 

Quality of the murmur --> Regurgitation vs Stenosis

If the murmur is stenotic, think of HARSH/RUMBLE SOUNDS. This is due to abnormal forward flow through stenotic valves, which should otherwise be open. Stenotic lesions lead to PRESSURE OVERLOAD.

 

Whereas, if the murmur is regurgitant, think of a BLOWING sound. This is due to abnormal backflow of blood (regurgitation), through an incompletely closed valve. Regurgitation leads to VOLUME OVERLOAD.

 

Murmur Chart

 

The Innocent Murmur

Another murmur that we often talk about is the innocent heart murmur or Still’s murmur.  This heart murmur sound will classically be “musical” and vibratory in quality.  It will be grade 1-3, midsystolic, and low-pitched (which is why you use the bell).  This murmur is best heard at the left lower sternal border and can radiate to the cardiac apex.  This murmur will most often be found in childhood to early adolescents. 

 

Since this is largely due to abnormal flow of blood through the heart, position will make this murmur better or worse.  Classically laying supine will worsen innocent murmurs whereas Valsalva will improve the heart sound associated with innocent murmurs.

 

Sources

  1. Southern Illinois University School of Medicine Physician Assistant Program. Heart Murmurs. 2016.
  2. https://www.nhlbi.nih.gov/health-topics/heart-murmur
  3. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6368429/
  4. https://www.ncbi.nlm.nih.gov/books/NBK525958/

 

 

This article or blog post should not be used in any legal capacity whatsoever, including but not limited to establishing standard of care in a legal sense or as a basis of expert witness testimony. No guarantee is given regarding the accuracy of any statements or opinions made on the podcast or blog