CHANGES IN THE CIRCULATORY SYSTEM - COMPLICATIONS OF DIABETES.
1. Arteriosclerosis, Almost all writers agree that diabetics from premature arteriosclerosis, and therefore are liable to all the troubles, such as cardiac asthma, and exposed to all the dangers, such as apoplexy, degeneration of the heart muscle, peripheral gan grene, necrotic inflammations, etc., which this condition calls forth. Perraro in particular has asserted, and with reason, that arteriosclero sis is the connecting link between diabetes and the parenchymatous glandular degeneration so commonly associated with it. Recently Laache has endeavored to trace a relation between the ueuralgias oc curring in diabetes and a precedent arterial disease. The arterio sclerosis occurring at a relatively early age sets forth in a most charac teristic manner a type of numerous nutritive disturbances in diabetes, viz., premature senile changes. The condition is more marked as a rule in the obese than in those of spare build, and is often far ad vanced before a diagnosis of diabetes is made.
It is a question that calls for careful study in the future whether arteriosclerosis, possibly of syphilitic origin, may not be often the primary disease which is followed later by diabetes resulting from the nutritive disturbances so occasioned in the pancreas or nervous sys tem. The forms of pancreatic disease most frequently encountered in diabetes, namely, necrosis, fatty degeneration, chronic interstitial inflammation, and atrophy, are precisely the ones which may be caused by enclarteritis.
2. The differ widely as to the condition of the heart in diabetes. Without question there are many patients in whom not the slightest cardiac lesion is present, or in whom the state of the organ corresponds merely to the general nutritive condition of the individual. When disease is present the abnormal deviation may occur in one of two directions : a. Hypertrophy of the Heart.—In post-mortem examinations of diabetics, 0. Israel found hypertrophy of the left ventricle present in 10 per cent. of his cases, I. Mayer in 13 per cent., and Saundby also in 18 per cent. In each case there were at the same time changes in the kidneys, especially true renal hypertrophy. The latter is due to the incTeased labor devolving upon the kidneys in the elimination of large quantities of water, urea, sugar, and salts. But 0. Israel does not regard this as a sufficient explanation of the cardiac lesion, and he believes that the irritation caused by the excrementitious sub stances circulating in the blood throws extra work on the heart and thus leads to hypertrophy of the organ. I. Mayer found hypertro phy of the heart in 24 out of 90 cases of diabetes (27 per cent.) dur ing life.
Cardiac hypertrophy in diabetes, as in most other morbid condi tions, is a welcome complication; for of itself alone it is never the cause of any distressing symptoms. Nevertheless the muscular tissue
of an hypertrophied heart shows a greater tendency than does that of the normal organ to subsequent exhaustion and weakness. The situation differs in no wise from that encountered in valvular troubles, contracted kidney, arteriosclerosis, etc.
b. Cardiac Weakness.—This condition either follows hypertrophy or arises independently of it. Its anatomical basis is often a simple atrophy of the muscle, as has been shown especially by the reports of post-mortem studies made by Frerichs. Associated with the atrophy there may also be fatty infiltration and dilatation. The atrophic heart is naturally found most frequently in those whose general con dition is much depressed, especially in those suffering from tubercular complications. Sometimes the etiological factor in weakness and muscular disease of the heart is a sclerotic process involving the coronary arteries.
Clinically weakness of the heart manifests itself in many cases by diminished bodily strength, asthmatic troubles, and a small irregular pulse; in some eases there is a tendency to tachycardia, in others rather to abnormal slowness of the pulse. But, on the other hand, there are cases in which no symptoms of cardiac weakness are present or at least are noticed, until finally with tolerable rapidity, sometimes even very suddenly, paralysis of the organ ensues and the patient dies asphyxiated with all the symptoms of "heart failure." These eases of sudden death have nothing to do with diabetic coma; it is to Frerichs that the credit is clue of having made a sharp distinc tion between the two conditions. The catastrophe occurs ordinarily after some great and unwonted exertion, such as a spell of mountain climbing or a fatiguing journey, or in consequence of some acute psychic disturbance. In view of this fact it is most important to ex amine with all possible thoroughness the condition of the patient's circulation ; and upon the results of this examination will be based the physician's advice as to the amount of bodily exercise which the patient may take.
r. Valvular Lesions.—Valvular insufficiency is often met with as an accidental complication arising from precedent polyarthritis, etc. At other times lesions of the valves, and then always at the aortic orifices, are found as a result of arteriosclerosis.
d. Neuroses of the Heart.—Cases of functional palpitation and stenocardia are common, being more frequently encountered, how ever, in individuals of a nervous temperament than in the phlegmatic. They are either a consequence of the fundamentally altered condition of the nervous system or are indirectly due to the diabetes in so far as the latter is the causal condition of the hysterical, neurasthenic, or hypochondriacal troubles. There is no proof of their direct de pendence upon the diabetes.