Functional heart murmurs : their causation and diagnosis / by Robert Dawson Rudolf.

  • Rudolf, Robert Dawson, 1865-1941.
Date:
1905
Catalogue details

Licence: In copyright

Credit: Functional heart murmurs : their causation and diagnosis / by Robert Dawson Rudolf. Source: Wellcome Collection.

Provider: This material has been provided by The Royal College of Surgeons of England. The original may be consulted at The Royal College of Surgeons of England.

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    either case it leads to leakage at the orifice, the normal cusps not being able to close the abnormally large opening. But in functional heart murmurs signs of dilatation of the heart are largely, although not entirely, absent, and it seems probable that the leakage which occurs at the auriculo-ventricular orifice is not due to stretching of the sphincter from general dilatation of the ventricular wall, but rather to the relaxation of the sphincter,—hypotonus of the muscle associated and probably due to the same causes as the general relax- ation of the vascular musculature. When dilatation of any hollow viscus having muscular walls, for example, the stomach, occurs, it arises from one of two causes, either an increased internal pressure, or a decreased tone of the muscular coat of the organ. Now in the case of the athlete’s heart the right ventricle becomes enlarged and the tricuspid valve leaks because the intraventricular pressure is abnormally high, just as the normal stomach may become dilated from the imbibition of a large quantity of fluid. On the other hand, in certain weakened conditions the ventricles, and especially the sphincters guarding the auriculo-ventricular orifices, may become dilated not owing to increased intracardiac pressure, but rather to decreased tonus of the muscular wall, just as very frequently the stomach becomes dilated from decreased tone in its wall without any distention by contents. It goes almost without saying that if both factors be present, dilatation of a hollow viscus will occur with exceptional ease. Thus, if an individual with his heart in a condi- tion of hypotonus run a race or otherwise exert himself, that heart will very easily dilate. Thus it is that in certain anemic or other- wise debilitated individuals functional mitral or tricuspid murmurs occur either without, or certainly with, only a slight amount of exer- tion. Lsennec, strange to say, attributed the functional “bellows” murmurs produced at the mitral and tricuspid orifices to a spasm of these orifices. He does not seem to have noted the murmurs at the base of the heart at all. Pulmonary Murmur.—Looking next at the functional murmurs heard over the base of the heart, we find that two distinct systolic murmurs occur here, one, a comparatively rare one, in the aortic area, and the other, a very much commoner one, in the pulmonary area. This latter is by far the commonest functional cardiac mur- mur that occurs. We may probably assume, as already mentioned,