.11Ielanosis.—This deposit is also found very distinctly in the heart. It appears in the form of small spots under the pericardium or endo cardium, or as tumours in the substance of the ventricle. In a specimen in the Museum of King's College, London, the melanotic deposits are situated, some beneath the pericardium covering the right ventricle, and others on the carnem columnm of the same cavity,im mediately subjacent to the endocardium. Neither Andral nor Bouillaud notices the occurrence of me lanosis in the heart.
Hypertrophy of the heart.—When the walls of any of the heart's cavities experience an in crease of thickness, owing to the developernent of the muscular substance, they are said to be in a state of hypertrophy; and there is no morbid state of this organ which is more fre quently brought under the notice of the phy sician than this, as affecting the parietes of one or more of its cavities. There is no alteration in the muscular texture apparent to the naked eye, except, perhaps, a slight increase of the red colour—the heart is firm, dense, and elastic ; in short, it presents all those characters which we so often see manifested in the ex ternal voluntary muscles, the developernent of which is increased by frequent use.* Hyper trophy may affect all the cavities simultaneously, but in general it is limited to one or at most two cavities. The left ventricle is that in which it most frequently occurs, next the right, and lastly and rarely the auricles. Nor does the hypertrophy affect necessarily the whole pa rietes of the cavity, but sometimes it is limited to a small portion, or to the septum, or to one or more of the carnem columnm. In some cases, as Andral remarks, the thickening may be at its maximum at the base of the heart, and diminish gradually towards its apex, which sometimes retains its natural thinness, when all the rest of the parietes are three or even four times as thick as natural ; or at other times, as Cruveilliier observes, becomes so thin that one is astonished that perforation or dila tation of the heart at its apex is not more com mon. In other individuals again the thickening is equal and uniform from the base to the apex, which then loses its pointed form and acquires a rounded shape. Lastly, it sometimes happens that the hypertrophy is greatest about midway between the apex and base of the heart, or is even exclusively confined to that part. When the septum is principally affected, the capacity of the right ventricle is so diminished that it sometimes looks like a small appendix attached to the left ventricle.* When the hypertrophy affects chiefly or exclusively the right ventricle, the apex of the heart seems to be formed by it, whereas in the normal state the apex belongs to the left ventricle.
An hypertrophous state of the parietes of all the cavities not only affects the form of the heart by changing it from the oblong to the spherical, but, as was first noticed by Dr. Hoped- its position is altered ; "as the dia phragm does not retire sufficiently to yield space downwards for the enlarged organ, it assumes an unnaturally horizontal position, encroaching so far upon the left cavity of the chest as sometimes to force the lung upwards as high as the level of the fourth rib or even higher." Bertint distinguishes three varieties of hy pertrophy of the heart. I. That in which the hypertrophy is not accompanied with any alte ration in the capacity of the cavities of the heart—simple hypertrophy. 2. That in which there is dilatation of the cavity along with the increased substance of its walls—excentric hypertrophy or active aneurism of Corvisart. 3. W here the capacity of the ventricle is dimi nished as if the walls had encroached by their increase of thickness upon the cavity, or as Bouillaud expresses it, as if the internal mus cular layers and the carnesi columnm were prin cipally the seat of hypertrophy—concentric hy pertrophy.§ Of these the most frequent is that which is accompanied by dilatation, the dilata Lion in all probability preceding and giving rise to the hypertrophy by rendering an increased force of contraction necessary. Simple hyper trophy is the least common, according to Boni'laud ; concentric hypertrophy, according to this physician, is not rare. Considerable doubt, however, has been excited recently by the high authority of 111. Cruveilhier as to the real existence during life of such a condition as this. This anatomist believes the diminished cavity to be merely the result of a tonic con traction of the muscular wall of the ventricle in death. " The concentrically hypertrophied hearts of Berlin and Bouillaud appear to me," he says, "to be hearts more or less hypertro phied, which death surprised in all their energy of contractility." The hearts of all those examined by Cruveilhier, who died by the executioner, presented to his observation to a great degree the double phenomenon of in creased thickness of walls and diminished cavity, and he has observed the same with per sons who died a violent death.t On one occa
sion I was particularly struck with a similar condition of the heart of a donkey which had been accidentally transfixed by a large trocar, whereby the death of the animal was caused in a few minutes. The muscular structure of the heart was singularly dense. It had contracted at its apex quite to a sharp point, and on cut ting into it the cavity of the left ventricle ap peared almost obliterated, and the muscular wall much increased in thickness. I have many times, too, observed the fact noticed by Cruveilhier, that the cavity may be easily en larged or restored to its natural dimensions by introducing the finger and dilating it, or still more easily, if the heart have been macerated in water for a short time previously. This fact is further confirmed by Dr. Budd, who sup ports the views of Cruveilhier in an interesting paper in the last volume of the Medico-Chirur gical Transactions. In one of Dr. Budd's cases the thickness of the parietes of the left ventricle eighteen hours after death varied from an inch to an inch and a half, on a transverse section made at a distance from the apex of one-third of its length, and the cavity was not large enough to hold the second phalanx of the thumb, and was almost filled by the camere columnar. This heart, in its open state, was put to macerate; noforce wasapplied to extend it. At the end of some days, on being folded up, it was found to have dilated very conside rably, so that the left ventricle could not then be said to be smaller than natural. Dr. Budd argues against the existence of the diminished cavity from the fact that of eight cases collected by him, no one afforded signs, either during life or after death, of any obstacle to the circu lation through the heart. There were no irre gularity of pulse, no dropsy during life, no di latation of the right cavities after death, pheno mena which, it may be said, must of necessity be present if there be an obstacle to the circu lation in the heart. It is impossible, as he states, to conceive that a left ventricle, which could scarcely hold an almond, should offer no obstacle to the circulation through the heart. Yet Lacnnec has recorded a case in which the parietes of the left ventricle had acquired the thickness of from an inch to an inch and n half, and the cavity seemed capable at most of con taining an almond stripped of its shell. Yet the day before the patient's death his pulse was natural, the breathing perfectly free, "and nothing," says Laennee, " led me to suppose that this man had a disease of his heart." Hypertrophy with dilatation.—It is in this morbid condition that the heart acquires the greatest increase of size as well as the most striking alteration of form. The cur bovinum of some authors, so called from its enormous size, affords an instance of an extreme develope merit of this form of disease. The extent to which the heart may become enlarged in this way is quite extraordinary. Of certain cases recorded by Bouillaud, in one the right ventri cle was large enough to contain a goose's egg, and the left, still larger, the closed hand of a female; in another, the left ventricle was simi larly increased in capacity. In a third, the right auricle of a child, aged seven years, was so dilated as to contain a coagulum as large as the closed hand of an adult. The thickness of the left ventricle in Bouillaud's cases varied from 7 to 14 lines, that of the right 3 to 5 lines; but in some instances it was as considerable as from 8 to 10 lines or 11 to 16 lines. The weight of the heart, in some instances, trebled the na tural ; thus in one case of general hypertrophy the weight was 22 ounces, and others weighed from 13 to 20 ounces. The circumference of the heart was often increased to twelve inches, the longitudinal diameter five inches, and the transverse eight inches. In a patient who died at the Hotel Dieu in 1834, the heart measured fifteen inches and a half at its base. Hypertro phy seldom occurs in the auricles, except when accompanied by dilatation : the musculi pecti nati are generally the seat of the increased mus cular developement, and as the number and developement of these muscular columns is greater in the right auricle than in the left in the normal state, (in the left they are only found in the auricular appendage,) the remark of Dr. Hope follows almost as a matter of course, namely, that in the right auricle hypertrophy proceeds to the greatest extent, its walls being sometimes rendered nearly equal in thickness to those of the right veotricle in the normal state.