Genghis Khan - Examine the history of the mongol empire as Genghis Khan united the tribes on his way to conquor most of the world Visit Genghis KhanInformational Site Network Informational
Privacy


Home


Medical Articles


Mother's Remedies


Household Tips


Medicine History


Forgotten Remedies


Search

Medical Articles

Rheumatism

We feel urged, in first considering this sore and very common ...

Scarlet-fever Or Scarlatina

is an eruptive fever, produced by a peculiar contagious poiso...

Diet And Corpulence

A tendency to obesity should always be carefully checked by at...

Pulmonary Phthisis Consumption

After tubercles have been formed extensively in the lungs, an...

A Collection Of Gallbladders

Gallbladder cases are rather ho-hum to me; they are quick to ...

Recent Wounds Contusions And Burns

Use the B D current, strong force as can be borne. Bring the ...

List Of Instruments

The following list has been compiled as a convenient basis f...

Onion Cases

All too many of my cases are what I privately refer to as oni...

Cramp In The Limbs

The treatment of this is to apply cold cloths to the roots of ...

Baths

During rheumatism the peripheral blood vessels are generally ...

Diet Economy In

Dr. Hutchison, one of our greatest authorities on the subject ...

Blood Pressure In Children

May Michael, [Footnote: Michael, May: A Study of Blood Pressu...

The Poor Start

For this reason it makes sense to take vitamins and food sup...

Consumption Prevention Of

This most insidious and deadly disease is caused by a tiny veg...

Introduction Of The Esophagoscope

The esophagoscope is to be passed only with ocular guidance, ...

Taking A Laryngeal Specimen For Diagnosis

The diagnosis of carcinoma, sarcoma, and some other conditio...

From The Hygienic Dictionary 2

Toxemia. [1] "Toxemia is the basic cause of all so-called dise...

Head Skin Of The

The nerves of sensibility are very largely supplied to the ski...

The Period Of Convalescence

under the usual drug-treatment, is, however, usually protract...

Myocardial Disturbances

While the myocardium is the most important muscle structure...



Disturbances Of The Heart In General





Category: Uncategorized
Source: Disturbances Of The Heart

Of prime importance in the treatment of diseases of the heart is a
determination of the exact, or at least approximately exact,
condition of its structures and a determination of its ability to
work.

This is not the place to describe its anatomy or its nervous
mechanism or the newer instruments of precision in estimating the
heart function, but they may be briefly itemized. It has now been
known for some time that the primary stimulus of cardiac contraction
generally occurs at the upper part of the right auricle, near its
junction with the superior vena cava, and that this region may be
the "timer" of the heart.

This is called the sinus node, or the sino-auricular node, and
consists of a small bundle of fibers resembling muscle tissue. Lewis
[Footnote: Lewis: Lecture in the Harvey Society, New York Academy of
Medicine, Oct. 31, 1914.] describes this bundle as from 2 to 3 cm.
in length, its upper end being continuous with the muscle fibers of
the wall of the superior vena cava. Its lower end is continuous with
the muscle fibers of the right auricle. From this node "the
excitation wave is conducted radially along the muscular strands at
a uniform rate of about a thousand millimeters per second to all
portions of the auricular musculature."

Though a wonderfully tireless mechanism, this region may fall out of
adjustment, and the stimuli proceeding from it may not be normal or
act normally. It has been shown recently not only that there must be
perfection of muscle, nerve and heart circulation but also that the
various elements in solution in the blood must be in perfect amounts
and relationship to each other for the heart stimulation to be
normal. It has also been shown that if for any reason this region of
the right auricle is disturbed, a stimulus or impulse might come
from some other part of the auricle, or even from the ventricle, or
from some point between them. Such stimulations may constitute
auricular, ventricular or auriculoventricular extra contractions or
extrasystoles, as they are termed. In the last few years it has been
discovered that the auriculoventricular handle, or "bundle of His,"
has a necessary function of conductivity of auricular impulse to
ventricular contraction. A temporary disturbance of this
conductivity will cause a heart block, an intermittent disturbance
will cause intermittent heart block (Stokes-Adams disease), and a
prolonged disturbance, death. It has also been shown that
extrasystoles, meaning irregular heart action, may be caused by
impulses originating at the apex, at the base or at some point in
the right ventricle.

In the ventricles, Lewis states, the Purkinje fibers act as the
conducting agent, stimuli being conducted to all portions of the
endocardium simultaneously at a rate of from 2,000 to 1,000 mm. per
second. The ventricular muscle also aids in the conduction of the
stimuli, but at a slower rate, 300 mm. per minute. The rate of
conduction, Lewis believes, depends on the glycogen content of the
structures, the Purkinje fibers, where conduction is most rapid,
containing the largest amount of glycogen, the auricular musculature
containing the next largest amount of glycogen, and the ventricular
muscle fibers the least amount of glycogen.

Anatomists and histologists have more perfectly demonstrated the
muscle fibers of the heart and the structure at and around the
valves; the physiologic chemists have shown more clearly the action
of drugs, metals and organic solutions on the heart; and the
physiologists and clinicians with laboratory facilities have
demonstrated by various new apparatus the action of the heart and
the circulatory power under various conditions. It is not now
sufficient to state that the heart is acting irregularly, or that
the pulse is irregular; the endeavor should be to determine whit
causes the irregularity, and what kind of irregularity is present.





Next: Clinical Interpretation Of Pulse Tracings




Add to del.icio.us Add to Reddit Add to Digg Add to Del.icio.us Add to Google Add to Twitter Add to Stumble Upon
Add to Informational Site Network
Report
Privacy
SHAREADD TO EBOOK


Viewed 1353