Prognosis.—The prognosis of cardiac neuralgia is at best doubtful, and, in many cases, positively bad in the highest degree. If the attacks occur for the first time in a patient who has passed middle life, and is physiologically old for his age, i. e., shows tendency to degenerative changes of vessels, arcus senilis, gray hair etc., they are of very gloomy import; more especially if any signs exist which make a fatty change in the ventricle probable, or if there be serious valvular lesions. The probability here is greatly in favor of a speedy fatal termination; if the first attack does not kill, a second or third very probably will; at any rate, the patient is not likely to survive any considerable number. If the attack occurs in a younger person, in whom there is not much likelihood that arterial degeneration has seriously commenced, or the heart-muscles become fatty, more especially if the attacks have been brought on by such an accidental circumstance as a very exhausting bout of mental or physical toil, then there is considerable reason to hope that the disease may soon wear itself out. Even patients who have serious valvular lesions may, with young and undegenerated tissues in their favor, quiet down again into a regular habit of semi-health, in which they may live for a long time without any recurrence of cardiac neuralgia. The more purely neurotic form, again, especially when it develops gradually out of some pre-existing chronic neurosis, such as asthma, is usually slow in its progress; and it may well happen, in such cases, that the danger to life is more on the side of serious nervous lesions than from the anginal attacks themselves. At the same time, it must be remembered that, even in the milder cases, any very unusual excitement, bringing on an unwontedly severe attack, may produce fatal results at any period of the disease.
There is some reason to believe that cardiac neuralgia is occasionally produced in a reflex manner in consequence of a severe existing intercostal neuralgia. I cannot say that I have witnessed any thing which can be considered as completely proving this; but it certainly seems likely that, in some of the few cases of excessively painful herpes zoster which have proved fatal (of which I have given one example), cardiac spasm or paralysis may have been secondarily induced, and may have occasioned the catastrophe. It is likely enough that, if this was the case, the reflex irritation operated upon motor centres which themselves were predisposed to take on the morbid action; but this again is a fresh illustration of the uncertainties to which prognosis is liable in a disease like angina, the very fundamental character of which is that, upon increase of the irritation, the gravity of the resulting functional affection is liable to be indefinitely and most rapidly increased.
Treatment.—The treatment of cardiac neuralgia is (1) prophylactic, and (2) palliative of the attacks.
As regards the prophylactic treatment, it is unnecessary to repeat the remarks which we have made elsewhere upon the general principles of tonic and nutritive medication in neuralgias of every kind. One especial prophylaxis, in the case of this formidable variety of neuralgia, is concerned with the preservation of the heart from certain disturbing influences which would render the occurrence of the fit more probable. All violent emotions and all strong physical exercise (but especially such forms of it as, like boating, are well known to "pump" the heart severely) are to be carefully avoided. Even indigestion and flatulence are to be carefully guarded against since these are quite capable of embarrassing the action of the heart to a degree which, though it might be trivial in the case of ordinary health, may prove fatal by exciting a flabby ventricle to irregular and embarrassing contraction. It is even possible that the strong irritation set up by some varieties of indigestible food might propagate an irritation to the spinal cord which would produce an interbitory paralysis at once.
But besides these obvious precautions against interference with the regular and tranquil action of the heart, there are some special medicinal remedies which deserve particular notice. Whether we really possess any means of so influencing the nutrition of the muscular tissue of the heart as to prevent its lapsing into a fatty degeneration, it is impossible to say; but this may be affirmed with some confidence, that, in cases where awkward threatenings of cardiac neuralgia have occurred, and simultaneously it has been noticed that the heart-sounds become weak and the circulation languid, a most marked improvement has been produced in all respects by the administration of iron and strychnia. I usually give tincture of sesquichloride of iron, ten minims, and strychnia, one-fortieth of a grain, three times a day. Still better, where it can be borne, is the syrup of the triple phosphate of quinine, iron, and strychnia, which undoubtedly has an extraordinary influence upon tissue nutrition, as exemplified in its remarkable effects in many cases of phthisis. It must be observed, however, that it is not every neuralgic patient who will bear the combination of quinine with iron; it has occurred to me to meet with several in whom the union of these two remedies proved violently disturbing to the nervous system, causing distressing headache and palpitation of the heart, which could not be attributed to any want of care in the apportioning of the dose, or in the mode of administration. Iron is more especially indicated, of course, in cases where there is anæmia; but there are some cases in which strychnia given alone seems to produce a very beneficial influence. (vide Chapter V., on "Treatment.")
By far the most important prophylactic tonic against cardiac neuralgia, however, is arsenic. That this drug should prove useful in cardiac neuroses might readily be anticipated from its very great utility in many cases of asthma, a disease which, as already remarked, has a close relationship to the former. Dr. Philipp has recently recorded a case which is perhaps an extreme instance of this beneficial influence of arsenic, but is none the less encouraging, especially as it only corroborates what has been advanced by other observers. Given in doses of from three to five minims of Fowler's solution, twice or thrice daily, arsenic is an invaluable remedy in cardiac neuralgia; the one objection to it being that some neurotic patients possess such an irritable intestinal canal that the remedy cannot be borne, as it produces diarrhœa. Even here we may sometimes succeed by combining it with very small doses of opium. It is more especially with regard to those cases in which the neurotic character of the disease is very prominent—i. e., in which the nervous temperament of the patient betrays itself in other ways besides the tendency to spasmodic embarrassment of the heart's action, that arsenic holds such a very high place as a remedy. And it should be carefully remarked that the prophylaxis of angina extends itself, in such cases, beyond the limits of actually-declared and well-defined angina, which is, of course, an uncommon disease. This remedy is important, and may be most usefully employed in the far larger group of cases in which a marked tendency to spasmodic pain in the chest, on the occurrence of some comparatively trifling excitement, is observed in patients who either have some organic heart-disease, or who are liable to severe attacks of asthma. It cannot be too often repeated that there is no intelligible separation, except one of degree, between these cases and the malignant forms of angina. It may be added that, in my experience, I have found the whole group of cases to be bound together in a singular way by the tolerance of arsenic which, with certain exceptions already referred to, they display. Commencing with the small doses above mentioned, I have found it possible, in many cases, to advance to the administration of twice or thrice the quantity, and to continue this medication for months together, not only with no evil effect, but with the best results.
Of zinc, as a prophylactic tonic in cardiac neuralgia, I know but little. Truth to say, it is a nervine tonic of occasional great value, but which, on the whole, I have found so unreliable that I am somewhat prejudiced against it; and perhaps have not given it a fair trial in those milder cases of cardiac pain to which it might be suited. It does appear, however, to have some preferential action on the vagus, and might therefore be possibly more useful than I am at present inclined to think it.
The treatment of the acute neuralgic stage itself is a matter in which we are sadly limited by the exigencies of the case. Relief must be excessively rapid if we are to save life in the most threatening cases, or to deliver the patient from a most prostrating agony, which might have lasted for hours, in other instances.
The remedy which the highest authority, Dr. Walshe, seems to put first in efficacy is opium; and he directs the dose to be measured by the intensity of the pain, as much as forty to sixty drops of laudanum being given in a severe case. He says, however, that it should be given with an antispasmodic, such as brandy, or ether, or sal-volatile; and I confess that I believe the antispasmodic treatment to be by far the most important. Indeed, so marked is the success which I have found to attend the use of ether in the paroxysm, that till lately I scarcely cared to make further experiments, with drugs, for the relief of the patient at this stage. One teaspoonful of ether in two ounces of thickish mucilage should be given at once, and repeated in a short time if the patient does not rally.
In a few instances, angina seems to be provoked by the irritation of indigestible food, and when there is good reason to suspect this an emetic should be given. I strongly recommend that mustard should be used for this purpose, for the effect of a mustard-emetic is by no means merely to empty the stomach, it has a powerfully rousing influence on the heart.