moistens and prevents the adhesion of the heart to the pericardium. (f>) CHAP. V. This fluid is sometimes found to exist in considerable quantity, to the Sect. I. amount of several ounces; but so large a quantity has been considered as Circulation. the effect of disease ; and it is a question, about which there have been many disputes, whether any perceptible quantity of the liquor pericardii exists during life, and in the state of health; and the better opinion seems to be that, in health only, a very small quantity can be detected, because as fast as it is discharged by one set of vessels, it is, in general, absorbed by another. But when in disease, these actions do not correspond, and when either the discharge is too rapid, or the removal too slow, an accumulation may take place, (c)

The heart may be subject to malformation or malconformation, such as Defects and the foramen in the septum of the auricles remaining open after birth, diseases of the and allowing a part of the venous blood of the right to enter the left hearu(d) auricle, and pass off into the general circulation unoxygenized. So the heart is liable to diseases, preventing the due oxydation of the blood, besides others which may affect the frame in general, (e) These are scarcely remediable, but though the art of medicine may be unavailing, yet it will be important to observe paliatives and preventives of consequences, and, in particular, perfect tranquillity, a light diet, and attention to the state of the bowels. (/) Malformations may be in the pulmonary artery, so as to prevent the blood from freely passing from the right auricle into the lungs, and being there renovated ; (g) or the aorta may be improperly placed ; (A) or, instead of two hearts, there may be a third, and each imperfect. In these cases life, in general, is very short and painful, subject to great difficulty in breathing, palpitation, fits, and sudden death, (i) Of these descriptions is the disease called Cyania, or blue skin, where the skin is more or less blue, the lips purple, with a general hebetude and inactivity, which is produced mostly by a connate congenital communication of the two ventricles of the heart, and, consequently, an imperfect discharge of the carbon of the blood in the lungs, which constitute the proper organ of its elimination, (j ) The heart, also, may be too small for the system to which it belongs, or too large. So the muscular walls of the heart are liable to increase, or diminution of their ordinary thickness. Without any apparent traceable cause, the walls of the ventricles, and, occasionally, of the auricles, increase in thickness and in the firmness of their texture, and the whole heart acquires a magnitude nearly double that of its original and healthy condition. This increase of thickness, to which the left ventricle is more subject than the right, may be attended with dilatation of the cavity, or otherwise. When it is accompanied with dilatation of the cavity, it is now technically called " active aneurism" of the heart. Its occasional cause

(f>) 1 Bost. 363; 1 Bell's Anat. 489; Lizars, part ii. p. 1, 2, 146, 147; 3 Good, 473; Quain's £1. 575; 3 Paris it Fonb. 56.

(c) 1 Bost. 363, 364.

(d) As to the effect of anger, &c, 4 Good, 121; and as to palpitation, see 4 Good, 449; and as to the diseases of the heart in general see Dr. Hope on Diseases of the Heart and Great Vessels; and see 2 Bell, 76 to 84; Forsyth, 41, 44; 2 Par. & Fonb. 178; Liz. 146,147; A. Burn on Diseases of the Heart; Abercrombie's contributions to the Pathology of the Heart, Trans. 1824; Dr. Laennec's Traite de

L'Auscultation Mediate et des Maladies
des Pournons et du coeur, 2d edit. 1826.
This last work is particularly interesting and
valuable, as are all the works of that author.

(e) 2 Bell, 56.

(/) 3 Good, 483.

(g) 2 Bell, 58.

(ft) Id. 59.

(i) Id. 56 to 70.

(j ) 3 Good, 482; 1 Bost. 352 to 354, 361, and quxre if this does not arise from an imperfect congenital communication of the two auricles, as above.

(fc) 2 Bell, 73 to 81; 2 Good, 492.

[ocr errors]

CHAP. V. is obstruction from disease of the semilunar valves of the aorta, but it Sect. I. may arise from various other causes. Again, the walls of the ventricles become soft and thin, so that even the pressure of the finger may rupture the texture of the wall without difficulty. This, when accompanied by dilatation of the ventricle, is called "passive aneurism." In this condition of the heart its walls may yield or give way, and occasion sudden death ; but such a rupture never occurs unless caused by external violence, nor without some previous degeneration of the muscular structure of the organ." (/)

But the aneurism of the aorta is a disease more frequent and more dreadful than all the others. It is a disease more frequent in the decline of life than at earlier periods. The aorta then begins to ossify; coat is converted into a hardish bony substance,

i various points, and extending throughout a considerable portion of the of the vessel. Thus the elasticity of the artery and its mu

calibre of the vessel. Thus the elasticity of the artery i
power is lost. In this state it may burst, and uniformly destroy life
instantaneously, (m) There may also be an aneurismal enlargement of
the larger vessels in the immediate neighbourhood of the heart, (n) These
disorders sometimes arise from too violent exertions, independent of all
predisposition; sometimes from blows; more frequently from shocks or
falls; but still more often from those kinds of exertions which are accom-
panied with a rapid pulse and hurried respiration, (o) As to the symp-
toms, palpitation and quick breathing are the most common, but these
maybe symptoms of quite different disorders, (p)

For aneurism of the aorta, rest, with abstemious diet, repeated small bleedings, issues in the region of the heart, and attention to tl tion by dietetic means, it is said, is all that can be done, (y) Angina Pec- I" a verv valuable recent publication Angina Pectoris, toris. breast pain, has been treated as a distinct disorder, arising from a i

disease in the heart or aorta, or both, or in some of its vessels too i accelerating the flow of blood, or suddenly increasing the action of the heart, and occasioning most agonizing pain, and which is to be treated differently during the paroxysm and in the interval, as there directed ; (r) and in Sauvages this affection is termed Cardiogmus Cordis Sinistic, importing that this disorder proceeds from the left side of the heart; (#) whilst, according to others, angina pectoris is to be classed amongst the diseases of the respiratory functions, and affecting the lungs, (s) But the affection was not recognized as a distinct disease by medical authors until Dr. Heberden described it as such in the Medical Transactions of the London College of Physicians; (*) and one of the ablest anatomists of the present time still insists, that angina pectoris is a symptom of more than one disease of the heart, and is not of itself a disease. Its seat seems to be usually in the heart, or in some of the organs of circulation, and not in those of respiration. It has by Dr. Copland, in his valuable work, been recently defined to be "acute constrictory pain at the lower part of the sternum, inclining to the left side, and extending to the arm, accompanied with great anxiety, difficulty of breathing, tendency to syncope, and feeling of approaching dissolution," and the alleviating remedies are there described, {s)

(I) I have been favoured with the above (j>) Bell, 87.

passage between inverted commas by a (g) Liz. part it p. 165,166.

most experienced anatomist. (r) Cyclop. Prac. Med. tit. Angina Pec

(m) Smith, 37; 2 Bell, 82, 83; Lizars, toris, 81 to 95.

part ii. p. 163,164,168. (s) Copland, Diet. Pract. Med. tit. Aa

(n) 3 Good, 473. gina Pectoris.

(0) 2 Bell, 85.

The notion of what is commonly termed a broken heart, merely from CHAP. V. mental suffering, seems to be questionable; and it is said that though Sect. I.

violent passions of the mind very commonly produce syncope, yet that "* HTr"lla'

the person must have laboured under some previous organic affection of Rupture or bro

the heart or its vessels if death ensue, (u) ken hcart-({)

Wounds of the heart, even of the slightest and most superficial kind, Injuries to the

have been generally considered as fatal, and the exceptions are few. heart, as

The heart cannot be wounded without the pericardium, which surrounds wouads-
it, being injured; but that membrane may be pierced without extend-
"le heart

ing to the heart itself, and wounds of the pericardium merely are not

".(*)

2. Of The Arteries, (y)

The Arteries have been termed vital agents, endued with the proper- Sect. I. ties of living matter, and forming part of an organized system endowed 2. Theartewith vital powers, and have an important share in the circulation of the RIESl blood, (2) and they are stated to be in number about 1000, (a) but at least, as regards the named arteries, there are not perhaps even 300.

Arteries are elastic canals or vessels receiving and conveying the blood from the heart to the different parts of the body, whereas veins carry back the blood from the different parts to the heart; arteries are also distinguishable from veins by their pulsation. It has been observed, that to the surgeon the knowledge of the arterial system is valuable beyond calculation or belief, for he can perform no operation in which arteries are not engaged, nor can he cure any great wound in which arteries are not first to be tied, and without a knowledge of the arteries he can neither reason correctly nor act safely. (6) Nerves accompany and influence the arteries ; the lymphatics and veins twine round them; the glands and various organs contain a large distribution of them. The intimate , structure of parts is known only by understanding such distribution of their vessels ; and as each individual part is nourished by arteries, he who has studied the arteries thoroughly, possesses a more general knowledge of the whole ; (c) so that every surgeon ought to learn familiarly the general distribution of the arterial system, (rf)

The original and principal trunks of the arteries, or of those which The pulmonary arise from the heart, are two in number, the pulmonary artery and aorta, *rtCTJ and tlle both of which are nearly of the same diameter ; and the measure of each, aortaon being slit, is about three and three-eighth inches, or, according to others, the area of the aorta is about three-fourths of a square inch, (e) The pulmonary artery arises from the right ventricle of the heart, and conveys the blood as there received from the veins into the lungs, where it is renovated and returned back, as hereafter described, to another part of the heart, and from thence the blood is propelled into the aorta. From the latter, all the other arteries are.derived, and branches are dispersed through the whole body, (f)

(t) Liz. part ii. p. 16; 4 Good, 121; as (c) 2 Bell, Introd. xxii.; 2 Good, 12,

to rupture of aorta of Geo. 2d, see 3 Paris 24.

& Fonb. 58 ; Smith, 37. (d) 3 Bell, Introd. 25, 26.

(u) 2 Paris & Fonb. 26, 27. (e) 1 Bost. 417.

(*) Smith, 277. (/) Ell. Blum. 82; 2 Good, 28;

iy) Angiology, Quain. 35, ante, 51. 2 Bell, 92; Liz. part ii. 170; Coop. Diet,

(i) 1 Bost. 391. tit. Aorta, 213,215, tit. Aneurism ; Cjclop.

(o) 2 Bell, Introd. xxv. ante, 5. same title, p. 104. (6) 2 Bell, Anat. Introd. 23; El. Blum. 81.

[ocr errors]

CHAP. V. It is the trunk from which the general tree of the arteries is to be Sect. I. explained. It commences deep in the flesh or muscles of the left side of The Arteries. ^ neart) an(j raounts upwards and backwards from the heart till it T°« Aorta and begins to form its peculiar arch or curvature, and then bends downwards ''"" to the left side of the spine opposite the third or fourth dorsal vertebra, along which it proceeds gradually, reaching the front of the spinal column through the diaphragm into the abdomen. At the commencement of the aorta the two coronary arteries branch from it, and proceed on the heart itself, in order to supply it and cause its successive contractions; and from the arch of the aorta go off three great arteries, which rise to the head, or bend sideways towards the arms, and so nourish all the upper parts of the body, viz. Jirst, the arteria innominata, dividing into the right carotid and right subclavian artery. Secondly, the left carotid artery, going to the head; and thirdly, the left subclavian artery, going to the left arm. (g)

The aorta in the chest nourishes die lungs hy the bronchial or small nutritient vessels, and when it gets below the diaphragm gives three great abdominal arteries; first, the cceliac, going in three branches, one to the liver, one to the stomach, and one to the spleen; secondly, the superior mesenteric, which furnishes all the smaller and a great portion of the large intestines; and thirdly, the lower mesenteric artery, which supplies a portion of the great intestines down to the rectum. The arteries of the kidneys and of the testicles may be added to these, and are branches of the aorta, and afterwards the aorta divides into two great branches for the pelvis and legs. The iliac arteries are the two great branches into which the aorta divides within the abdomen, and these again are each subdivided into two great arteries, the internal iliacs to supply the pelvis, and the external iliacs to go to the thigh. These are only a very few of the principal great arteries; and there are a great many others, formed by successive divisions and subdivisions of these, which are distributed to every part of the body, receiving names according either to their size or to the importance of their distribution. (A) The vena cava, proceeding upwards, leaves the aorta a little above the pelvis, and inclines gradually towards the right, that it may enter into the right side of the heart, which it does by passing under the liver, and penetrating the diaphragm, (t)

The principal trunks run in the centre or deepest and most protected parts of the body and extremities, where they are the least exposed to danger, deriving support or defence from the bones and muscles, (k) They are distinguished from veins by the whiteness of their colour and thickness of their coats; also in the circumstance of their not having like veins any valves, except at the roots of the aorta and pulmonary artery. (J) Arteries thus commencing from the aorta or from themselves are found to terminate in several ways, as by one artery anastomising or inosculating, that is, communicating with another, or in red veins, or in glands or follicles, by secerning or secreting orifices which separate a fluid from the general mass of blood by exhalent vessels, whioh discharge their contents into the internal cavities, or upon the external surface of the body; and finally, arteries terminate in that structure called erectile tissue, (m) Other authors observe, that in the present state of our knowledge the umbilical vessels are to he regarded as the only exceptions

(g) 2 Bell, 93, 94. (fc) 2 Good, 25, 26; Tuson, 101.

(h) Id. 221. (I) 2 Good. 13; 1 Bost. 340.

(i) Id. 97 to 321; see an eneumera- (m) Ell. Blum. 83; Tujon, 102 j 2 dan and plates 3 Gregory's Economy of Good, 3. Nature, 243 to 255.

to the termination of arteries in veins ; (n) at all events many of the CHAP. V. arteries do not terminate immediately in veins, but in some degree the Sect. I. effete and altered blood in the arteries first passes into the capillaries, the Arteries. which are hair-like terminations of the arteries, and thence into the incipient radicles of the veins, which convey it into the larger branches, from which it is forwarded to the trunks that open into the right auricle of the heart, (o) Dr. Good says, that in reality the capillary system constantly intervenes between the arteries and the veins. ( p) Many physiologists insist that the large arteries are merely mechanical tubes to convey the blood to remote parts, and the capillaries, in which the arteries terminate, as the part of the vascular system in which all the important objects of the circulation are mainly prepared and accomplished as nutritious secretion, the oxidation of the blood, its decarbonization, &c. (q) The distinction between artery and veins at the point of union is lost, (r)

Every artery has its sheath, which is a tissue of cellular membrane surrounding it, and material to be distinguished by the surgeon from the artery itself. («) Each artery also has or rather is composed of three arterial coats, now generally termed external, middle, and internal. (<) The exterior, by some called the tunica cellulosa propria, by others the nervous cartilaginous tendinous, &c, and is composed of condensed cellular membrane, externally more lax, internally more and more compact, and blood vessels are seen creeping upon it; and it gives great tone and elasticity to the arteries. The middle coat consists of transverse fibres, lunated or falciform, and almost of a fleshy nature; hence this has the name of muscular coat, and appears to be the chief seat of the vital power of the arteries, and is the chief assisting power propelling the circulation of the blood. The inner coat, lining the cavity of the arteries, is highly polished and smooth, but which is much more distinct in the trunks and larger branches than in the smaller vessels. («)

The powers of an artery in moving forward the blood are elasticity and muscularity. Their elasticity marks their difference, from the veins keeping their sides apart and open, even when they are empty; and the muscular power increases in the proportion in which the artery is remote from the heart, which compensates the decreased power of the heart the greater the distance from it, and thus the blood is circulated with nearly equal velocity throughout the arteries, (x)

Dr. Bostock makes the following observation on the arteries:—The arteries which perform the office of conveying the blood from the heart are flexible elastic tubes, not perfectly cylindrical, but conical, the narrower end of the cone being situated towards the heart, (y) The arteries are principally composed of membranous matter, formed into distinct layers, and composing what are called the coats of the arteries. Of these membranous coats, anatomists usually describe two as possessing a sufficiently determined structure to be easily distinguished from each other, the outer one partaking more of the nature of the cellular texture, and therefore called the cellular, (z) and an inner membrane, white, firm, and smooth, possessing more of the physical properties of tendon, and by some erroneously called the nervous coat, but more properly the interior

[ocr errors][ocr errors]
« PreviousContinue »