Sources: Disturbances Of The Heart
While disease of the coronary arteries may occur without general
arteriosclerosis, it is so frequently associated with it that it is
necessary to give a brief description of the general disease.
Arteriosclerosis or arteriocapillary fibrosis is really a
physiologic process naturally accompanying old age, of which it is a
part or the cause, and it should be considered a pathologic
condition only when it occurs prematurel
. It may, however, occur at
almost any age after 30, and is beginning to be frequent between 40
and 50. In rare instances it may occur between 20 and 30, and even
in childhood and youth. It is much more frequent in men than in
women. Its most common cause is hypertension; in fact, hypertension
generally precedes it. The most frequent cause of hypertension today
is the strenuousness of life, the next most frequent cause being the
toxins circulating in the blood from overeating, overdrinking,
overuse of tobacco and the overuse of caffein in the form of coffee,
tea or caffein drinks. Another common cause of arteriosclerosis
occurring too early is the occurrence of some serious infection in a
person, typhoid fever and sepsis being most frequent. Syphilis is a
frequent cause, especially of that form of arteriosclerosis which
shows the greatest amount of disease in the aorta. Mercury used in
the treatment of syphilis is more liable, however, than syphilis to
be the cause of arteriosclerosis. Although this drug, even with the
arsenic injections now in vogue, is necessary for the cure of
syphilis, it probably tends to raise the blood pressure by
irritating the kidneys and by diminishing the thyroid secretion,
both of these occurrences predisposing to arteriosclerosis. From the
fact that lead poisoning causes an increased blood pressure, lead is
a probable cause of arteriosclerosis. With the greater knowledge of
the danger of poisoning possessed by those who work in lead, chronic
lead poisoning is becoming rare, as evidenced by the lessening
frequency of wrist drop and lead colic.
Chronic nephritis is often a coincident disease, but the causes of
the arteriosclerosis and the nephritis are generally the same.
Alcohol, except as a part of overeating and as a disturber of the
digestion, is perhaps not a direct cause of arteriosclerosis, as
alcohol is a vasodilator. Hard physical labor and severe athletic
work may cause arteriosclerosis to develop, and it is liable to
develop in the arteries of the parts most used.
Hypertension is generally a prelude to arteriosclerosis, and
everything which tends to increase tension promotes the disease;
everything which tends to diminish tension more or less inhibits the
disease. Therefore a subsecretion of the thyroid predisposes to
arteriosclerosis, and increased secretion of the suprarenals
predisposes to arteriosclerosis, the thyroid furnishing vasodilator
substance and the suprarenals vasopressor substance to the blood.
Furthermore. if these secretions are abnormal, protein metabolism is
more or less disturbed.
While arteriosclerosis often occurs coincidently with gout, and gout
apparently may be a cause of arteriosclerosis, still the two
diseases are widely dissociated, and the causes are not the same.
Although the arterial pressure has been high before arteriosclerosis
developed, and may remain high for some time in the arteries, unless
the heart fails, the distal peripheral pressure, as in the fingers
and toes, may be poor in spite of the high blood pressure. When the
left heart begins to fail, pendent edema readily occurs.