Pathogony

As regards the pathogony of chancre, inoculation furnishes us with a valuable means of producing at pleasure the pathological kind, the characters of which we are anxious to study, and affords us the opportunity of watching its development from the very first moment of its existence.

Notwithstanding the great advances that have been made during the last few years as to the pathogony of the nervous system, I am not aware of any published observation that would throw light on this case.

If the false anginas recognize different causes and pathogonies (distension of the cardiac cavities through generalized arterial spasms or vaso-motor troubles, dilatations of the heart consecutive to gastro-intestinal affections, neuralgia of the cardiac plexuses, etc.), true angina, on the contrary, explains itself by an invariable pathogony; it is due to the lesion of the cardiac arteries, to their sclerosis, to their contraction; it is most frequently the result of an aoritis, upon the condition that the latter intersects and partly closes the opening of the coronary arteries (pericoronary aortitis), and the paroxysms of angor are provoked by a temporary cardiac ischaemia, a veritable intermittent claudication of the heart, as M. Potain so judiciously remarks, who compares the products of the anginous attacks to what happens in the case of intermittent claudication of the extremities through incomplete obliteration of the iliac arteries.