given, in order to allay the irritability of the endocardium. For in like manner as an alkaline medicine combined with opium allays both a morbid secretion from the kidneys and an irritable state of the bladder, or that tenesmus, is subdued by opiates, whilst appropriate medicines are given to correct the morbid secretions of the alimentary canal, so will neurotics, especially camphor, ammonia, and hydrocyanic acid, be advantageously combined with haematics in the treatment of functional disturbances of the heart.

Much, too, depends on the air which we breathe; for as I have already mentioned, notwithstanding the atmospheric air contains the same proportion of oxygen and nitrogen in all situations, yet there are other elements which, although they have not See page 459. been defined, undoubtedly exist, and have a great influence upon

the animal œconomy.

In the treatment of functional disorders of the heart, we ought not, therefore, to neglect the benefit which may be derived from the changes on the vital element which are produced by climate.

"The national character and the mere grave and gay dispositions of men are dependent, in a very high degree, on climatic influence. The poetry of the Greeks, and the ruder songs of the primitive northern nations, owe great part of their peculiar cha- Humboldt's racters to the aspect of the plants and animals seen by the bard and the mountains and valleys which surround him, and to the air which he breathed."

When the functions of the heart have been disordered from the blood being changed, there must sometimes be more or less difference in the quantity contained in the heart's cavities; and in such cases great benefit will be derived by the abstraction of a small quantity of blood by leeches, from the precordial region. Should even the quantity of blood within the heart not be greater than what is required for health, yet that quantity may be superabundant in disease, so that the abstraction of a portion of it would be useful.

The employment of bloodletting in cases of this description is, indeed, a nice point to determine. But whenever the propriety of the measure becomes a matter of doubt, it is generally a safe rule to adopt the depletion, the application of a few leeches not

Physiogno

my of Plants.

Morgagni.

being likely to do much harm; whereas the loss even of a small quantity of blood may be essentially beneficial.

There is one symptom in the maladies which we are considering, which I would venture to affirm seldom fails to point out the propriety of abstracting blood. Whenever a spontaneous hæmorrhage has taken place from the ethmoidal, from the pulmonary, or from the hæmorrhoidal vessels, it may be considered as an effort of the vis medicatrix to relieve congestion, and in such cases the application of one or two leeches to the precordial region will seldom fail to assist in relieving the heart. "My son," says Wierius, "while at Bologna, pursuing his studies, had this afflicting palpitation, accompanied with a capricious, frequent, and intermitting pulse; but by bleeding, which the older physicians never neglected, and care, and relaxation from his studies, he got quite well."

On the other hand, serious mischief has often arisen from the improper use of bloodletting; a tumultuous action of the heart and uneasy sensations in the head, produced by a diminished proportion of arterial blood having often led the incautious physician to abstract blood, the effect of which has been to lesson in place of adopting those means which would increase the action of the heart.

CHAPTER XXIII.

FUNCTIONAL DISEASES OF THE HEART FROM DISORDERS
OF THE NERVOUS SYSTEM.

Phenomena and causes of the nervous affections of the heart; they arise either from disturbances in the nervous centres, or in the ganglionic nerves; general character of these two classes of nervous affections; affections of the heart caused by diseases of the cardiac nerves; these nerves are both sensory and motor; illustrated in angina pectoris and palpitation; pathological inferences; affections of the heart caused by disturbed associations of the nerves of the ganglionic system; their physiological and anatomical symptoms; diagnosis and treatment; the sympathetic affections; their symptoms, diagnosis, and treatment.

servations.

HITHERTO our inquiries have been directed to those diseases in G neral obthe heart's functions which are produced by changes in the quantities and in the qualities of the vital fluid; but there remains to be considered another class of functional disorders, which depend upon the influence of the nervous system-an influence which is exercised on the heart either directly by the cerebro-spinal nerves, or through the medium of that sympathy which subsists between the heart and the other organs with which it is associated by the ganglionic nerves.

Derangements in the heart's functions from diseases of the nervous system may be therefore, it appears to me, with propriety subdivided into two classes.

In the first class, the action of the heart is deranged by the morbid conditions of the nerves of the cerebro-spinal system; and in the second class, by disturbed associations of the nerves of the ganglionic system.

Two classes ous affections

of the nerv

of the heart.

Anat. Géné

This arrangement, I think, will be found practically useful, and Bichat not inconsistent with physiological science; for, though some rale." may not admit that there are two distinct systems of nerves, and that the ganglionic is not independent, but is subordinate to the

See Chap.

VIII.

the cerebrospinal sys

cerebro-spinal system, yet, in a pathological point of view, they may be considered as separate and distinct; diseases in the one taking place from the great nervous centres, and communicating directly with the heart; and in the other arising from the relation which subsists between the cardiac nerves and those viscera which are supplied by nerves of the ganglionic system.

But, whilst admitting this division of the nervous system in our pathological inquiries, we must not lose sight of the intimate relation which subsists between the cerebro-spinal and ganglionic nerves; a relation which is established by the ganglionic system being formed by nerves from both of the great nervous centres and it is by this relation that we can explain the phenomena of many of the nervous diseases of the heart.

I have already endeavoured, at some length, to point out the Influence of effects of derangements of the cerebro-spinal system upon the heart, and to show that the consent of these two vital organs depends on both the connexion which subsists between the heart and the brain, in virtue of nervous filaments, and by the influence of the blood on the cerebro-spinal system.

tem,

and of the ganglionic system.

See page 110.

and of the cardiac nerves.

The cardiac

nerves are

The disorders of the nervous system which disturb the functions of the heart, may arise either from some primary affection of the cerebro-spinal nerves, or of the cardiac nerves; these being derived from the ganglionic system.

The influence of mental emotions on the heart's functions have already been fully explained; in all the diseases of the brain and spinal cord, various changes being produced in the functions of the heart.

Influenced, as the actions of the heart must be, through the medium of the nervous filaments which come from the brain, like other organs it also has its special nerves, the various conditions of which all influence its functions; and, whilst the cardiac nerves regulate and control the actions of the heart, the heart, in its turn, when its functions are deranged, disturbs the cardiac nerves.

The progress that has been made in physiological science may both sensory essentially contribute to assist our investigations on the pathology of the cardiac nerves. For, as it has been observed, that in diseases of the spinal cord the sensory and the motor columns are

and motor.

separately affected, so it will be found, that in one class of the nervous diseases of the heart, the sensory, and in the other the motor, nerves are disordered.

The morbid condition of the sensory nerves are characterised by uneasy sensations and pain; and when the motor nerves are affected, there is an inordinate muscular action, of which phenomena we have striking illustrations of the first, in the angina pectoris, and in the second in palpitation. At the same time, it should be noticed, that both systems of nerves may be affected in particular examples of disease, as is often observed in the nerves of other organs.

The first class of these affections of the cardiac nerves, or of their sensory branches, are a feeling of anxiety and uneasiness, sometimes amounting to severe pain, in the region of the heart, frequently extending along different branches of the nerves of the chest, neck, and usually the left shoulder, from whence they extend down the arm. The degree of pain, however, which those suffer who are afflicted with a disease of the heart, is not always to be taken as a just criterion of the extent or danger of the malady, many lingering ailments having no influence on the sensory nerves.

Morbid senscardiac

ations of the

nerves.

pectoris.

The painful sensations to which the name of angina pectoris Angina has been given is a vague term, like that of palpitation or headache, being employed to signify a distinct disease; whereas, it merely expresses some nervous symptoms which are common to many of the heart's maladies. There is, indeed, no affection of the heart the pathology of which has been rendered more obscure than angina pectoris; a confusion which has arisen not only from the symptoms having been attributed to very different morbid conditions of the heart by different observers, but also from all those symptoms which are described as appertaining to angina being met with in many organic as well as functional diseases of the central organ.

That such an assemblage of symptoms should be always caused by a change in the structure of the coronary vessels, to which angina has been generally attributed, is not the case; for there are abundant proofs of these vessels being greatly diseased, and not accompanied with neuralgic symptoms. And there are also

Consult the writings of

Parry, Jen

ner, Heber

den, Mor

gagni, and

Haller.