Correspondence

A Grade 6 Systolic Murmur

N Engl J Med 1999; 341:1472-1473November 4, 1999

Article

To the Editor:

Presumably, the grade 6 murmur that was audible without a stethoscope (and without applying the ear to the chest?) and that was represented by the echocardiogram in the July 1 Image in Clinical Medicine by Spodick and Pezzella1 had a musical quality. I say this for several reasons. First, as demonstrated by spectral phonocardiograms obtained in the 1950s,2 musical murmurs owe their quality to harmonics, and gross harmonics in systolic movement of the mitral valve are a striking feature of the M-mode echocardiogram submitted by Spodick and Pezzella. In the second place, such loud murmurs are probably always musical. They are caused by the periodic, and therefore musical, vibration of a structural member, driven at high energy by the regurgitant stream. The vibrant member in this case was the endocarditis-damaged mitral valve. Noisy murmurs, which constitute the majority, are caused by turbulence and do not generate the high level of energy characteristic of many musical murmurs.1

Other examples of loud musical murmurs are those generated at the aortic valve: calcific aortic stenosis, the murmur of which may display the Gallavardin phenomenon — that is, the selective transmission of the musical component toward the cardiac apex but location of the noisy component (jet noise) to the right of the upper sternum, with transmission toward the carotids — and regurgitant aortic valve, the murmur of which may have a musical component if the structure of the valve is affected in a particular way by bacterial endocarditis or syphilis. In the past, some of the loudest diastolic musical murmurs were caused by syphilis of the aorta, which led to the creation of a retroverted lip of tissue that vibrated in the regurgitant stream, resulting in a “wood-sawing” or “sea-gull” murmur.

In summary, probably all grade 6 murmurs are musical, at least in part, but not all musical murmurs, by any means, are grade 6.

Victor A. McKusick, M.D.
Johns Hopkins Hospital, Baltimore, MD 21287-4922

2 References

1. 1

   Spodick DH, Pezzella AT. A grade 6 systolic murmur. N Engl J Med 1999;341:27-27
   Full Text | Web of Science | Medline

2. 2

   Murmurs. In: McKusick VA. Cardiovascular sound in health and disease. Baltimore: Williams & Wilkins, 1958:202-23.
   

Author/Editor Response

The authors reply:

To the Editor: Dr. McKusick is quite correct about the musicality of this grade 6 murmur (which was audible without applying one's ear to the chest) and other very loud murmurs. His list might also have included prolapsed aortic-valve cusp. Dr. McKusick mentions transmission characteristics, including the traditional site: the carotids. Yet, systolic and many diastolic aortic-valve murmurs are better transmitted to the clavicles than to the carotids, as can be predicted on the basis that there is better transmission of vibrations by solid than by soft tissue.1

David H. Spodick, M.D., D.Sc.
A. Thomas Pezzella, M.D.
Saint Vincent Hospital, Worcester, MA 01604

1 References

1. 1

   Spodick DH, Kerigan AT, de la Paz LR, Shahamatpour A, Kino M. Clavicular auscultation: preferential clavicular transmission and amplification of aortic valve murmurs. Chest 1976;70:337-340
   CrossRef | Web of Science | Medline