630 



ABNORMAL CONDITIONS OF THE HEART. 



HEART, ABNORMAL CONDITIONS 



OF. There is no organ in the body in which 

 the variousdeviations from the normal state have 

 been more diligently or more carefully explored 

 than the heart ; nor ought it to be otherwise, 

 when we take into account the important part 

 which the heart performs in the organism, and 

 the serious nature of the derangements which 

 its diseases in general produce, how many or- 

 gans and how many functions are involved in 

 the break-up which too often follows the oc- 

 currence of morbid alterations of the heart. 

 The great frequency* of diseases of this organ, 

 and the manifest and tangible shape which these 

 diseases assume, as well as the little liability 

 of its component structures to those appearances 

 which have been denominated pseudo-morbid, 

 these circumstances render it comparatively 

 easy to detect and observe its abnormal condi- 

 tions. To one who has made the natural 

 condition of the whole organ, as well as of its 

 several parts, the subject of careful study, 

 there is no field of investigation in morbid 

 anatomy which presents fewer difficulties. 



The records of anatomy are not without in- 

 stances of total absence of the central organ of 

 circulation (acardia); and it may well be 

 supposed that such cases would also afford 

 examples of the defective development of other 

 not less important organs. In short, it is in ace- 

 phalous and anencephalous fetuses that the heart 

 is most frequently wanting, although its ab- 

 sence is not, as some observers suppose, a con- 

 stant characteristic of these forms of monstro- 

 sity ; nor on the other hand does acardia ne- 

 cessarily imply acephalia or anencephalia. 

 Thus in the case recorded by Marriguesf, and 

 quoted at length in Breschet's Memoir Sur 

 I'Ectopie du Car,Jthe brain was present, while 

 all the usual contents of the thorax were 

 wanting, their place having been supplied by 

 a large bladder full of clear water which occu- 

 pied the whole thoracic cavity. The details 

 of another case were communicated many 

 years ago to the Royal Society by Sir Benjamin 

 Brodie, and are published in the volume of 

 their Transactions for 1809. The foetus was 

 one of twins, as is most frequently the case 

 when the heart is absent. The brain was 

 " nearly the natural size, and nothing unusual 

 was observed in it." The heart, thymus gland, 

 and pleura were absent, and the lungs most 

 imperfectly developed. The aorta, however, 

 was tolerably perfectly developed, but as a con- 

 tinuation of the umbilical artery extending 

 from the left groin upwards on the fore-part of 

 the spine to the upper part of the thorax, where 

 it gave off the two subclavian, and afterwards 

 divided into the two carotid arteries without 

 forming an arch. The external and internal 

 iliac arteries of the left side came from this 

 artery in the left groin immediately after it left 

 the umbilicus, and the common iliac of the 



* Out of 520 post-mortem inspections recorded 

 by Dr. Clendinning, 170 were cases of diseased 

 heart, or about 33 per cent. Vide his Croonian 

 Lectures for 1838, Med. Gazette, vol. xvi. p. 6o7. 



t Mem. de Mathcm. pros, a 1'Acad. dps Sc. t. iv. 



J Rep. Gen. d'Anat. et de Physiol. i. ii. 



right was given off from it in the lumbar region 

 after it had gained the situation of the aorta. 

 We shall first examine the congenital devia- 

 tions from the normal state in this organ, and 

 secondly its morbid alterations. 



I. Congenital abnormal conditions. These 

 are observed under three heads. 1. Congeni- 

 tal aberrations of position, or ectopise of the 

 heart. 2. Malformations by defect in deve- 

 lopement. 3. Malformations by excess of de- 

 velopement. 



1 . Congenital aberrations of position. The 

 simplest form of malposition is that in which 

 the heart retains the vertical position which it 

 occupies during the early periods of imra-ute- 

 rine life ; but of this the authentic instances are 

 rare.* Better known is that deviation in which 

 the heart is directed downwards, forwards, and 

 to the right side. This malposition generally 

 occurs as a part of a universal transposition of 

 the abdominal and thoracic viscera, of which 

 many well-marked examples are now on re- 

 cord ; however, it sometimes, although more 

 rarely, exists alone without ectopia of any 

 other organ. Breschetf records four cases of 

 this latter kind. Otto} has met with three in- 

 stances, and many other examples are scattered 

 among the records of anatomists. In this 

 form of transposition of the heart, the aorta 

 sometimes passes down along the right side of 

 the spine, and at other times down its left side. 

 In the latter case the transposition is not so 

 complete, the ventricles retaining their natural 

 position with reference to the anterior and pos- 

 terior aspects of the body. Again the heart 

 may be pushed too much to the left side, as a 

 mechanical result of congenital diaphragmatic 

 hernia of the right side; and it has been 

 found laid across in the chest from one side to 

 the other, the apex being at one time directed 

 to the right side, and at another to the left, 

 or turned upside down, the base toward the 

 abdomen, or in that cavity, the apex upwards 

 still remaining in the thorax. 



In such cases as have been just detailed, 

 the heart still retains its title to be considered 

 as a thoracic viscus ; but other and more re- 

 markable malpositions of it have been found, 

 where it is excluded from that cavity. These 

 are, in fact, congenital thoracic hernise in va- 

 rious directions, of which Breschet, whose 

 memoir already referred to contains the most 

 complete account of this subject, enumerates 

 three principal varieties, according to the situ- 

 ation in which the heart is found, viz. the 

 superior or cervical displacement, the abdo- 

 minal or inferior, and the thoracic or anterior. 



Thus Breschet details a case in which the 

 heart, lungs, and thymus gland were all con- 

 tained in the anterior part of the neck, forming 

 a large tumour under the lower jaw. The 

 point of the heart was attached to the base of 

 the tongue, and placed between two branches 

 of the lower jaw. The thorax was occupied 



* Sandifort, Obs. Anat. Path. 



t Op. cit. 



t Sell. Beobacht. part i, p. 95, and part ii. p. 47. 



$ Retiss' Repertorium, vol. x, p. 90-91. 



