Stokes Adams Disease Heart Block
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Disturbances Of The Heart
Stokes-Adams disease, or the Stokes-Adams syndrome, is a name
applied to a combination of symptoms which was described by Stokes
in 1846, and had been observed by Adams in 1827. The disease is
characterized by bradycardia and cerebral attacks, either syncope or
pseudo-apoplectic or convulsive attacks.
To understand the phenomena of this disease, it will be well to
refer to the first chapter of this book.
ntil 1893, when His
described the bundle of muscle fibers which is now known by his
name, the transmission of the cardiac stimulus to contraction was
not understood. It has been found, by studying the pathology of
Stokes-Adams disease, as well as by clinically noting with
instruments the contractions of different parts of the heart, that
these slow heart beats are really due to interruptions of the
impulse passing from auricle to ventricle through the bundle of His,
and degeneration in this region is generally the cause of Stokes-
Adams disease. The auricles often beat many times more frequently
than the ventricles, even two or three times as frequently, and, of
course, these auricular contractions are not transmitted to the
arterial system, and the radial pulse notes only the contractions of
the ventricles. The phrase that is used to describe this
nontransmission of the auricular stimulus to the ventricles is
"heart block."
While this disease almost invariably has a pathology, cases have
occurred in which no lesion of the heart could be found, but it
generally occurs coincidently with arteriosclerosis, in which the
coronary arteries are more or less involved and the arterial system
of the brain may be diseased. It occurs more frequently in men than
in women, and in them mostly after middle, or in advanced, life. The
previous history of the patient has often disclosed syphilis. The
intermittence of the pulse may be regular or irregular, and may not
be constant in the early stages of the disease; but when the disease
is established, the rate of the pulse may be reduced to forty,
thirty, or even twenty beats a minute, and it has been known to be
even less. When these intermittences are regular, perhaps two beats
to one intermittence, or three beats to one intermittence are the
most frequent types. When the auricles also beat slowly, perhaps the
vagiare for some reason overstimulated and thus inhibit the heart's
activity.
The attacks of syncope are doubtless due to anemia of the medulla,
because of the infrequent ventricular contractions. This anemia of
the medulla and of the brain may also cause an epileptic seizure, or
a partial paralytic seizure without any apparent paralysis. It is
probable, however, that in these cases there may be coincident
arterial disease in the brain. These sudden syncopal attacks are
likely to occur when a patient suddenly rises from a reclining
posture, especially if he has been asleep. Many persons whose
circulation is none too strong may feel faint on suddenly rising,
but in a person whose pulse is slow and the circulation weak the
danger of causing anemia of the brain by the sudden erect posture is
much increased. Slight faint turns are of frequent occurrence with
these patients; or the faintness may be so rapid and so intense that
the patient may drop in his tracks. Venous pulsation in the neck is
generally marked, showing an impeded contraction of tile right
auricle.
If the auricles are heard or found by instrumental readings to
contract more frequently than the ventricles, the trouble is quite
likely to be a heart block from disease in the heart itself, in the
bundle of His. If the heart is slowed as a whole, the trouble might
be due to diseased arteries or pressure from a growth, a gumma,
perhaps, or other brain tumor in the region of the pons Varolii or
medulla oblongata; or a hemorrhage into the fourth ventricle,
causing pressure, could be the cause.