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heard ; and on the contrary, on carrying the stethoscope upwards, from the heart towards the subclavian artery, an intermediate point was found, where the cardiac murmur was lost and the subclavian murmur began to be heard. There were thus distinctive evidences of two seats for the two murmurs; and the same evidences would, I presume, be present in all similar complicated cases. I had, again, another example, where subclavian murmur existed with loud aortic murmur, and this latter murmur was in truth reflected nearly into the subclavian region. But several differences were detected on careful inquiry, by which the diagnosis was determined. For example, the two murmurs had each a different sound; the subclavian murmur could be stopped by inspiration, by the movement of the arm, and by pressure of the stethoscope; while the aortic murmur was persistent in all these conditions; and a last but excellent point was, that the radial pulsation, which was synchronous with the subclavian murmur, followed the aortic murmur.
I do not think there could be two better marked examples of subclavian murmur, complicated with aortic and mitral murmurs, than those above given. Without further comment, they supply in themselves all the differential diagnostic points to which it is necessary to call the attention of the reader.
Pleural friction-sound may be mistaken for subclavian murmur, or the murmur may be mistaken for friction-sound, but not if care is taken. One of my
pupils once showed me a patient who had, he believed, the subclavian murmur ; but, on re-examination, the sound proved to be frictional. The character of the sound was certainly closely analogous to a sharp subclavian whiz, and the position was right for such an occurrence. But the diagnosis was clearly in favour of pleuritic friction : for (a) the sound heard was only present during inspiration, and was but one sound in the full period of inspiration; the arterial sound would have been repeated as frequently as the pulse. (6) The sound heard was not modified by the position of the arm. (c) The sound was still heard when the stethoscope was applied with sufficient firmness to stop the arterial pulsation altogether, and to check the radial pulse.
These three distinctions were in themselves suffi. cient, as physical signs, to indicate the nature of the case. To them, nevertheless, were added other general symptoms; viz., pleuritic pain increased by a deep breath, a small irritable pulse, and feverish exacerbations. Such symptoms, truly, were compatible with subclavian murmur and tubercle; but, coupled with those which are already named, they completed the evidence, and rendered an almost perfect diagnosis quite perfect. In any other analogous case, similar diagnostic rules would be afforded, in part at least, if not in the whole.
I have met with one case in which, together with subclavian murmur, there was, with chronic bronchial inspiration in the right subclavian region, a sharp bronchial coo immediately behind the artery. The patient was young, twenty-three years old, had suffered long from bronchial cough, and at the time of my first seeing him had been losing flesh and spitting blood. I was undecided as to the concurrent existence of tubercle; for a sharp bronchial coo at each inspiration covered the physical indications, even if present, of this deposit. At the point under the clavicle where the bronchial sound was heard, there could also be brought out during a deep inspiration a sharp subclavian murmur. But the distinction between the murmur and the bronchial whistle was clearly to be distinguished. In tone and timbre they were nearly the same, but in time they were different; for while the bronchial sound was as one to an inspiration, the subclavian ran on to three, both kinds of sound being heard as distinctly as two parts in a musical scale; added to this, there was the influence of differing positions of the arm, which modified the subclavian murmur, and did not modify the bronchial coo: while, again, the effects of firm stethoscopic pressure stopped the arterial, but in no way affected the bronchial sound.
This case clears the way for diagnosis between the arterial and the bronchial cooing murmurs.
Absolute Diagnosis. The absolute diagnosis of subclavian murmur is as follows.
It is a murmur beneath one or both of the clavicles, confined to the subclavian regions, and synchronous with the pulse.
The murmur is coarse and loud-a rasp; or sharp and musical-a whistle; or soft and musical-a coo; or shot-like, coming down on the ear bluntly and dead.
The murmur is always to be arrested by pressure, sufficient to check the pulse at the wrist, made by the stethoscope on the subclavian artery.
It is susceptible of modification by the movements of respiration. A moderately full inspiration may develope it; a very deep inspiration may either intensify it or stop it. A prolonged expiration will often remove it.
Movements of the arm modify the sound. The position of the arm when it is nearly down by the side of the patient gives, mostly, the minimum of intensity. The position of the arm slightly raised above the right angle to the body is that in which the maximum intensity is usually gained; while movements between these extremes produce varying gradations of both the quality and the frequency of the murmur.
In extreme cases there is to be felt, on application of the finger over the artery at the point where the murmur is heard, a marked fremitus, of which the patient may be conscious as well as the operator.
RELATIONSHIP OF SUBCLAVIAN TO
It will be seen, by reference to the table on page 8, that of the 2000 cases from which that record was compiled, there were 10 instances where the disease is classified as anæmia. In these cases there were bloodlessness and debility, but no physical indications of disease or consolidation of the lung; while, in the cases of murmur in the phthisical and bronchial diseases, the murmur was intensified where anæmic concomitant symptoms were most obvious. I have explained the possible cause of this in a previous page. I am anxious now to state that this fact does not of necessity connect pure subclavian murmur with those examples of anæmic murmur in the neck and heart, which we so often find in children, and in young women suffering from extreme anæmia or chlorosis. I have, indeed, met with no case of pure subclavian murmur in a child, and with but three instances in the female subject. Moreover, in all cases of pure anæmic murmur, whether cervical or cardiac, I have for the last two years sought for the subclavian murmur, but have never met with it as peculiar to such cases. The examples of anæmia from which this inference is drawn amount to somewhat above two hundred. The subclavian murmur, therefore, may be considered as independent of the common anæmic murmur. The two may coexist; and I have shown that the subclavian murmur is intensified by an anæmic condition of blood; but the connection does not extend further.
It is also to be observed that common subclavian murmur exists, as a general rule, without analogous murmur in any other part of the arterial system. But I have met with an exception to this rule. In one case of intense hypertrophy of the heart with mitral regurgitation, there was loud arterial murmur