Etiology
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Disturbances Of The Heart
The cause of an irregularly acting heart in an adult may be organic,
as in the various forms of myocarditis, in broken compensation of
valvular disease, Stokes-Adams disease, coronary disease, auricular
fibrillation, auricular flutter, cerebral disease, and toxemias from
various kinds of serious organic disease. The cause may be more or
less functional and removable, such as tea, coffee, alcohol,
tobacco, gastric indig
stion and intestinal toxemia; or it may be
due to functional disturbances of the heart, such as that due to
what has been termed extrasystole, or to irregular ventricular
contractions. A frequent cause of irregular heart action in women,
more especially of increased rapidity, is hyperthyroidism.
There may be an arrhythmia due to some nervous stimulation, probably
through the pneumogastric, so that the pulse varies abnormally
during respiration, being accelerated during inspiration and
retarded during expiration more than is normally found in adults.
This condition is frequent in children, and is noticed in neurotic
adults and sometimes during convalescence from a serious illness.
Nervous and physical rest, with plenty of sleep and fresh, clean air
so that the respiratory center is normally stiniulated, will
generally improve this condition in an adult.
Extrasystoles causing arrhythmia give a more or less regularly
intermittent pulse, while the examination of the heart discloses an
imperfect beat or the extrasystole which is not transmitted or acted
on by the ventricles, and hence the intermittency in the peripheral
arteries. This condition may be due to some toxemia, nervous
irritability, or some irritation in the heart muscle. Good general
elimination by catharsis, warm baths to increase the peripheral
circulation, a low diet for a few days, abstinence from any toxin
which could cause this cardiac irritation, extra physical and mental
rest, sometimes nervous sedatives such as bromids, and perhaps a
lowering of the blood pressure by nitroglycerin, if such is
indicated, or an increase of the cardiac tone by digitalis if that
is indicated, will generally remove the cardiac irritation and
prevent the extrasystoles, and the heart will again become regular.
It should be carefully decided whether there is beginning heart
block or beginning Stokes-Adams disease, in which case digitalis
should not be used. This disease is not frequent, while
extrasystoles of a functional character are very frequent. Sometimes
this functional disease persists without any apparent injury to the
individual as long as the ventricle does not take note of these
extra auricular systoles and does not also become extra rapid. If
the ventricle does contract with this increased rapidity, it soon
wears itself out, and the condition becomes serious.
In this kind of arrhythmia, if there are no contraindications to
digitalis, it is the logical drug to use from its physiologic
activities, slowing the heart by its action on the vagi and causing
a steadier contraction of the heart; clinically this treatment is
generally successful. If digitalis should, however, cause the heart
to become more irritable, it is acting for harm, and should be
stopped.