Sources: Disturbances Of The Heart
Chronic myocarditis may develop on an acute myocarditis, but is
generally a slowly progressive chronic process from the beginning;
it occurs mostly in persons past middle life, and as a rule is not
primarily associated with rheumatism or valvular disease of the
heart. Perhaps generally the term "chronic myocarditis" is
incorrect, as a real inflammatory condition is not present and has
not been present; it is really a degenerative process with the
development of connective tissue, a fibrosis and more or less
hardening of the arterioles, a cardiosclerosis. In many instances
this fibrosis is associated with fat deposits or fatty degeneration.
The disease is often caused by a narrowing or obstruction or
calcareous degeneration of the coronary arteries, thus diminishing
the blood supply to the heart muscle. This chronic myocardial
degeneration is often a part of the general arteriosclerosis, and is
an important factor in what is termed cardiovascular-renal disease.
In simple chronic renal diseases the heart first normally
hypertrophies to overcome the increased blood tension and increased
The principal causes of this degeneration are normal old age, or
premature age caused by various conditions. In other words, anything
which hastens arteriosclerosis will cause myocardial degeneration.
The causes recognized as most frequently producing this condition
are syphilis; gout; repeated attacks of rheumatism; excess in the
use of alcohol (meaning repeated daily too large amounts, as well as
actual dipsomania); the overuse of tobacco; excess in drinking tea
or coffee; general overeating, and excessive eating of meat in
particular, if the organs of elimination do not work perfectly and
if such eating causes or allows putrefactive changes in the
intestines; and progressive, prolonged wasting diseases, such as
tuberculosis and cancer. It has also seemed in some cases that the
only cause was excessive, hard physical labor, including excessive
athletic work, and in other cases that prolonged anxiety and worry
have been causes of cardiac degeneration and actual cardiac failure.
Prolonged absorption of toxins from mouth and tonsil infections may
be a not infrequent cause.
These myocardial changes are sometimes associated with chronic
pericarditis and chronic endocarditis, and may accompany or follow
valvular disease of the heart. Failure of compensation in valvular
disease and dilatation of the heart are sequences which occur sooner