As for the state of the muscular fibre which immediately causes death, Dr. Walshe is of opinion that it is paralytic rather than spasmodic; and he urges in favor of this view the fact that in his large experience he has never known the pulse to intermit during the attack--it was always regular, however feeble. In this respect he is in opposition to some distinguished authors, however, and, as he allows that he has not seen original attacks in their height, but only when they were subsiding, it would be possible that the spasm stage had subsided. However Dr. Walshe admits that there may be exceptional cases in which spasm, or cramp (_i. e._, spasm with rupture or dislocation of fibre), really occurs, and suggests that this is very probable in the rare cases where death is attended by general tetanic spasm of the muscles. As far as my own opinion is worth anything, I could insist that at least Dr. Walshe must be right as against Dr. Latham and Dr. Inman, in affirming that cardiac cramp, if it occurs, is the consequence and not the cause of the neuralgic pain.
_Causes._--In some respects it is impossible to deal with the etiology of angina apart from the pathology, just as we remarked with regard to neuralgias in general. But there are certain special features in the causation of angina pectoris which require separate notice, just as there are special features in its pathology.
Of predisposing causes, the majority are the same as those of which we have spoken in our general remarks on the etiology of neuralgia. A family history of a tendency to the graver neuroses is I believe universal, and, indeed, direct inheritance of angina from father to son, as in Arnold's case, has happened in many recorded instances. A very remarkable fact is the time of life at which the disease originally appears: Walshe says it is rare before the age of fifty, but excessively rare before forty. This is very interesting, as placing angina in the same category with the severe and intractable forms of facial and other neuralgias which are so highly characteristic of the period of bodily degeneration. One may even gather a suspicion, though it goes but a short way toward proof, that the essence of angina is an atrophy either of the cardiac plexus or of the nucleus of the vagus, or of that part of the spinal cord, already mentioned, which seems to be the centre of the major part of the propulsive force of the heart.