The murmurs of mitral disease / by Edward Mansfield Brockbank.

  • Brockbank, E. M. (Edward Mansfield), 1866-
Date:
1899
Catalogue details

Licence: Public Domain Mark

Credit: The murmurs of mitral disease / by Edward Mansfield Brockbank. Source: Wellcome Collection.

    16/92 (page 6)
    THE CAUSATION AND RHYTHM OF THE CRESCENDO MURMUR OF MITRAL STENOSIS- Definition.—By the crescendo murmur of mitral stenosis, I mean that abnormal heart sound generally called presystolic, and less often auricular systolic, which is practically diagnostic of obstructive narrowing of the auriculo - ventricular valve orifices, especially on the left side of the heart. Though the true crescendo murmur is diagnostic of stenosis of the mitral and tricuspid valves, several observers have described a murmur which they call presystolic, as occurring in other cardiac lesions, and even in dilatation of these same valves. I shall deal with this latter murmur in a future paper, and in the meantime will confine my remarks to the true crescendo murmur of mitral or tricuspid stenosis, and especially of the former affection. Nature of the Murmur. — The characteristics of the crescendo murmur are known to everyone, but there are one or two points to which I wish to direct special attention. The murmur is short and vigorous, and evidently produced by some strong force. It immediately precedes, and terminates abruptly with, the closure of the mitral valve, an event which is generally marked by an accentuated first sound of the heart, and invariably by the true cardiac impulse. The essential and most peculiar characteristic of the murmur is that it rises progressively from low to high pitch, like an ascending scale of notes, as it rushes rapidly to its abrupt termination. It is also generally of a true crescendo character—that is, it gathers in power of tone coincidently with its progressive rise in pitch. By the abrupt termination of the murmur at its stage of most complete development, the two important features of rising pitch and increasing force are emphasised. There are, broadly speaking, two types of crescendo murmur, both of which terminate abruptly with the first sound of the heart,