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condition may extend throughout the whole of the muscular system, causing a general tetanic constriction.
In prolonged cases of cardiac apnea occurring in children, as in examples where the symptoms arise from fibrinous deposit on the right side of the heart, there is very frequently emphysema of the lungs progressing to such an extent that the chest-wall is raised anteriorly: in the cases specified, the occurrences named are certain indications of cardiac obstruction in the right cavities, and of apnoea dependent upon that cause.
In all cases of death from cardiac apnea, the final act is one of persistent muscular contraction; the heart first failing, the muscles of the chest become fixed from tonic spasm; the voluntary muscles follow next; and the whole body, left more or less rigid, may pass into rigor mortis without any intervening relaxation of the muscular organs.
With these symptoms of cardiac apnea during the manifestation of an acute paroxysm, we must not fail briefly to recall those which are preliminary, in chronic cases, and which may be said to give the idea of a predisposition to an acute attack. One of the earliest symptoms, then, of impending cardiac apnea, a symptom which is often experienced for years before the disease marks itself out in its determined character, is a sensation of sinking and exhaustion over the region of the heart. This sensation comes on upon very slight exciting causes: such as deprivation of food, worry, a little overwork, or any excitement. A determinate act of the mind to bear up against this sensation will sometimes temporarily relieve it: a glass of stimulant taken with warm water will always relieve it: a moderate meal will do the same; or lying in the recumbent position. In some persons these exhaustive signs occur at particular times of the day; as at noon, or in the evening, or at the period of going to rest.
For many months, or even for years, the central exhaustion thus depicted may cause no serious inconvenience. The subject of it may become irritable and excitable, or perhaps melancholic, distrustful, and complaining; but those about him attribute these indications to nervousness or mental irritation. At length some telling event corrects this error: it is seen that the patient often becomes struck with faintness and pallor; that he cannot sleep at night; that his faculties are at times unsteady; and that a small amount of exertion produces breathlessness and objective anxiety. Upon these changes there is quickly engrafted an unmistakable acute apneal paroxysm, and the extreme extent of the disorder is revealed.
The physical diagnosis, in examples such as are now cited, is often, if it be put into practice, exceedingly trustworthy, and capable of shedding a light, too truthful to be happy, over the prognosis of the case. The first fact that strikes the auscultator is an absence of any pulmonic disease of a kind adequate to the production of the general symptoms; for, as a general rule, the lungs are free from any serious disorganisation or change. Turning to the heart, he notices next, in a vast majority of cases, that there is no murmur, and no evidence of valvular obstruction. In place of indications of valvular mischief, there is, however, a sign which is specially symptomatic. This is irregularity of action. In instances where this irregularity admits of analysis, the hesitation observed is found to occur in the systole. There are a few strokes of perfect rhythm, lub-dúp-pause; then lub-dūp-dúp-pause-důp-dúp; and now again in rhythm, lub-dŭp-pause. The patient himself is not conscious of this irregularity of the stroke as a particular fact ; for there is always a column of blood in the arteries waiting to be pushed on by the systole, and hence one hesitation during a fair interval of naturally repeated strokes is not specially felt. In one patient, who was a long time under my care, the systolic sound was sometimes suspended for such a long period, that it seemed to me impossible that some effect of which the sufferer was sensible, should not be felt. But I was wrong : for, on listening, I would arrange that on a stamp of my foot the patient should note his sensations at that moment; and, although I invariably gave the indicated sign at periods when the intermission was longest, yet I never gained any fact of a peculiarity of sensation, nor observed any obvious indication of failure of power on his part.
And yet persons affected with this cardiac irregularity often tell the physician that they feel, at particular times, a symptom which they attribute to irre. gularity of the heart : this symptom is a creeping, rising sensation, commencing in the cardiac region, and ascending sharply into the pharynx; it occurs often after food, or at the moment of falling to sleep; it is very oppressive, and a source of great alarm to nervous people. It is always present in persons who are predisposed to cardiac apnea, but it may be present in others; and it does not depend on an intermittent systole of the heart. It is, I believe, a temporary spasmodic twitch, commencing in the diaphragm, and communicated to the @sophagus: or else it is a reflex act from the terminal branches of the vagus to the branches supplying the pharynx. Any way, it is not cardiac; for during its presence the heart may be beating in the most perfect time and tune. I have said that persons predisposed to cardiac apnea always experience the sensation just delineated; this depends on the circumstance that such person are inevitably sufferers from dyspepsia. The dyspepsia, I believe, always precedes the cardiac malady, and is, indeed, the basis of it, and a continual attendant.
Together with this dyspepsia, there are soon established an irregularity of the cerebral circulation, attended with frequent giddiness, occasional pains in the head, whistling sounds in the ears, and now and then with dimness of sight: these symptoms all contribute to render the person subject to them immeasureably unhappy; and hence, even in early stages, such persons become melancholic and utterly despondent. In two such examples, which came before my notice, the patients committed suicide; and in a • third instance an attempt at suicide, nearly fatal, was made. The cases, in fact, of this kind constitute an almost distinct series of themselves; the subjects of them running the round of the whole Æsculapian fraternity, satisfied with nobody, and responding to no treatment, however rationally devised.
PATHOLOGY OF CARDIAC APNA. In studying the pathology of cardiac apnea, we are led naturally in all cases to the heart or the great blood-vessels, as the seats of the morbid changes upon which the symptoms depend. In our previous survey, we have seen, incidentally, a variety of morbid phenomena as attendant on cases of the kind named; so that in this place it is unnecessary to do more than recall attention rather more systematically to these morbid conditions.
The most common lesions in the circulatory system by which cardiac apnea is produced, are thinning and degeneration of the cardiac walls. These changes may present at least three general types. First, a change in which the muscular structure seems to have undergone a general atrophy and softening, without any actual intramuscular fatty deposit. The muscular tissue in these cases may indeed retain, to a large extent, its natural structural elements ; but it has undergone waste, and the fibre is consequently thinned and flabby. This form of degeneration commences, I believe, most frequently on the right side of the heart, giving rise in the first stages of change