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therefore a double systolic as well as diastolic murmur, in the period of one action of the heart; which is impossible.

We are driven thus to the third explanation, which seems, indeed, to answer every purpose. Thus, if in any given case there is set up an obstruction to the current of blood from the right auricle to the lungs, the current through the aorta from the left ventricle being free, the left ventricular systole will be made before the right ventricular systole; and the obstruction in the pulmonary circuit will prevent, for a period abnormally long, the return contraction of the pulmonary artery, and the closure with tension of the right semilunar valves. The two sets of semilunar valves will in this way be prevented from acting simultaneously, and the common sound produced by their tension will not be struck in the same period. The aortic valves coming down first, under these circumstances, will strike one diastolic sound, in the normal period of the diastolic sound; the pulmonary valves, lagging behind, will come down later, and strike a second sound in the period of the pause ; and then the systolic sound will follow in its natural place, and in its natural intensity. This was, I believe, the order of events in the case which forms the text of this essay; and the same are the events, I presume, in all cases of reduplication.

The same view that accounts for the physical cause of reduplication, accounts also for the general symptoms which accompany the physical phenomenon. The balance of the circulation is disturbed in

these examples, and the results are obvious. The oppression of respiration, amounting, as it did in my cases, to partial asphyxia, indicated with sufficient clearness the embarrassment of the pulmonary circulation; the deficient respiratory murmur defined the same fact: the palpitating heart indicated the labour demanded to support two cardiac currents unfairly balanced; and the inability to sleep free of disturbance showed the perpetual necessity for constant and undiminished action of the forces of respiration and circulation to meet the difficulties in their way.

But that which most of all indicated the nature of the reduplicative phenomenon in the text case, was the result of the treatment. Let us mark the fact specially. As soon as a powerful derivation was set up by the hot bath; as soon as the vessels of the skin, expanding under the heat, claimed more blood, and so relieved the lungs; so soon was the pulmonary and systemic balance restored, and the patient cured. He felt, indeed, as he expressed, that the oppression which had wearied him for weeks passed from him altogether.

DIAGNOSIS OF REDUPLICATION. I can recall no other abnormal sound, which could be confounded with that of reduplication. The absolute diagnosis is as follows: a physical condition of the heart during which, on listening to the cardiac sounds, three sounds take the place of two, the last of the three occupying, or nearly so, the period of pause.

The added sound, during ordinary respiration, fills the place of the pause partly or altogether. The sound is that of the diastole or second sound; short, and with an accent, dúp. It is heard most distinctly over the position of the pulmonary and aortic orifices. It is attended with symptoms of increased and irregular action of the heart, oppression of the breathing, and feeble respiratory murmur.

I have, so far, treated the subject of reduplication of the sounds of the heart with special reference to reduplication of the second sound; and this for the reason that as yet I have never met in my practice with any case in which the added sound could be considered as connected with the true systolic sound. It is but fair to say, however, that most competent observers, amongst them Dr. Cockle, Dr. F. C. Webb, and Dr. Walshe, have met, as they believed, with illustrations of systolic reduplication.

In these examples, the character of the abnormal sound must stand as lūb-lūb-dūp; and the cause of the additional sound must be due to the circumstance that the ventricular action of the two ventricles is not synchronous, and that, as a result, the tension of the tricuspid and mitral valves is not produced at the same instant. Now, while this event of irregularity of tension between the tricuspid and mitral valves is possible, and is, I believe, occasionally the fact, it is difficult to explain how by such occurrence a double first sound could be heard with a single second sound, seeing that the second sound itself is not a mere follower of the first, but is dependent for its

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production primarily on the systole. For unless either ventricle contract with sufficient force to distend the artery emerging from it, aortic or pulmonary, there can be no resistance, and no back stroke to close the semilunar valves and produce a second sound; and, as it is impossible that ventricular contraction can take place without tension of the auriculo-ventricular valves, and, therefore, without a systolic sound, so it would seem equally impossible that a first sound should occur twice without a second sound following immediately upon it. A condition such as is described would then give a double first or second sound in the period of one arterial pulsation—a phenomenon which, I believe, has never been met with.

At the same time, there are conditions, as I have before said, when the ventricular walls being greatly weakened and irregularly weakened, there is an irregularity of contraction. Here, however, the auscultatory phenomena are of two kinds, according to the degree of feebleness of the two contracting ventricles; in one of these cases one ventricle contracts with sufficient force to produce valvular tension, while the other produces but feeble tension, and the effect is a weakened systolic sound ; in another set of cases both ventricles contract so feebly as to produce imperfect valvular tension on both sides, the effect being to produce a confused rustle, in which no systolic sound can be detected, and often but a feeble second sound. We meet with this frequently in cases of large disorganized heart, when the muscular structure has undergone extensive degeneration, with thinning of the parietes.

From these observations, I should infer that what is considered a repeated first sound is, in fact, the first intensified stroke of a double second sound; but I would not venture to offer these remarks dogmatically, and as necessarily true, although the explanation carries to my own mind the conviction of a truthful rendering of a difficult problem.

BEARINGS ON PRACTICE AND TREATMENT. The study of those cases in which reduplication of one of the heart's sounds is detected, opens to us various considerations having relationship to other affections marked by analogous general symptoms.

I believe that in many of these cases, where there are symptoms of palpitation, oppression of breathing, especially during sleep (nightmare), and irregular pulse, the symptoms, usually attributed to indigestion, are due to a disturbed balance between the pulmonary and the systemic circulations. This want of balance may arise from different causes: from temporary congestion of lung after an undue supply of food to the system ; from irregular contraction of the heart under the influence of disease affecting one or other ventricular wall; from pressure on the diaphragm by collection of flatus in the stomach and intestines.

Treatment. There is nothing more obvious than the fact that, in the treatment I pursued in the case which affords the subject of the present commentary,

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